Manitowoc Ice G1200 Service Manual

This product qualifies for the following listings:
e
Recycled
aper
Series
G1200
SERVICE MANUAL
|
at
me РЯ
ni
ДИ МК
= /
ICE MACHIN ES
G6SVCVR
We reserve the right to make product improvements at any time. Specifications and design are subject to change without notice.
Part No. 80- 0846- 3
Rev 1 (8- -92) 5
MANITOWOC ICE, INC.
2110 South 26th Street P.O. Box 1720
Manitowoc, WI 54221-1720
Phone: (920) 682-0161
Fax: (920) 683-7585
Web Site: www.manitowocice.com
© 1999 Manitowoc ice, Inc.
Litho in U.S.A.
и - .
a ,
Ne
GENERAL SPECIFICATIONS
This section is not intended to be a guideline to install
the ice machine. Refer to Installation Manual for
installation procedures.
Ambient Air Temperature: 35°F minimum, 110°F
maximum (minimum five-inch clearance rear and sides)
Ice Making Water Supply:
Pressure — 20 psi minimum, 80 psi maximum
Supply Line — 3/8 inch
Drain Line — 3/4 inch
Water Temperature — 33°F minimum, 90°F maximum
Water-Cooled Condenser Water Supply:
Water Regulating Valve Setting — 240 psi + 5 (Factory
preset)
Pressure — 20 psi minimum, 150 psi maximum
Supply Line — 1/2 inch up to the 3/8" FPT connection
Drain Line — 1/2 inch
Temperature — 33°F minimum, 90° maximum
Heat of Rejection (BTU/Hr):
Average 20,000, Peak 31,700
Refrigerant R502:
Air-Cooled — 56 oz.
Water-Cooled — 38 oz.
Remote — 18 Ib.
ELECTRICAL REQUIREMENTS
Voltage AIR WATER REMOTE
Phase Maximum Minimum Maximum Minimum Maximum Minimum
Cycle Fuse/Circuit Circuit Fuse/Circuit Circuit Fuse/Circuit Circuit
Breaker Ampacity Breaker Ampacity Breaker Ampacity
208-230/1/60 30 25.1 30 25.1 30 26.4
208-230/3/60 20 15.4 20 15.4 20 16.8
220-240/1/50 30 21.2 30 19.9 30 21.2
220-380/3/50 15 9.2 10 7.9 15 9.2
Numbers Listed Are Amps
MANITOWOC ICE MACHINES ARE AIR CONDITIONING REFRIGERATION INSTITUTE (ARI) CERTIFIED
AND RATED IN ACCORDANCE WITH AIR CONDITIONING REFRIGERATION INSTITUTE STANDARD 810-87
NOTE
Test conditions for standard ratings at 90°F air, 70°F water, and 30 + 2 psig water inlet pressure.
Model Capacity Potable Water Condenser Water Power Input (KW/HT.
Designation (Lb. per 24 Hr.) Used (Gal. per Used (Gal. per 100 Lb. of Ice)
- | 100 Lb. of ice) 100 Lb. of Ice) -
GR-1200A 967 19.6 —— 6.4
GD-1202A 1040 19.6 —— 6.0
GY-1204A 1040 19.6 -— 6.0
GR-1201W 1050 19.6 172 5.2
GD-1203W 1130 19.6 172 4.8
GY-1205W 1130 19.6 172 4.8
GR-1290N 958* 940% 19.6 —— 6.5
GD-1292N 1030* | 10107 19.6 -- 6.0
GY-1294N 1030* | 10107 19.6 -- 6.0
*With AC 1295A Remote Condenser
#With DC1295A Remote Condenser
WARRANTY INFORMATION
IMPORTANT
Read this section very carefully for warranty ex-
planation. (Refer to Warranty Bond for complete
details.)
OWNER WARRANTY
REGISTRATION CARD
Warranty coverage begins the day the ice machine is
installed.
IMPORTANT
To validate the installation date, the OWNER WAR-
RANTY REGISTRATION CARD must be mailed in.
If the card was not returned, Manitowoc will use the date
of sale to the Manitowoc Distributor as the first day of
warranty coverage for your new ice machine.
About Your Warranty
Contact your local Manitowoc representative or our
Wisconsin factory for further warranty information.
WARRANTY COVERAGE
(Effective for Ice Machines Installed after
January 1, 1991)
Parts
1. The ice machine is warranted against defects in
materials and workmanship under normal use and
service for three (3) years from the date of the
original installation. It is important to send in the
warranty registration card so Manitowoc can begin
your warranty on the installation date.
2. An additional two (2) years (five years total) warran-
ty is provided on evaporator and compressor from
the date of original installation.
Labor
1. Labor to repair or replace defective components is
warranted for three (3) years from the date of
original installation.
2. An additional two (2) years (five (5) years total)
labor warranty is provided on the evaporator from
the date of original installation.
Exclusions from Warranty Coverage
The following items are not included in the warranty
coverage of the ice machine.
1. Normal maintenance, adjustments and cleaning as
outlined in the Use and Care Guide.
2. Repairs due to unauthorized modifications to the
ice machine or the use of nonapproved parts
without written approval from Manitowoc Ice, Inc.
3. Damage from improper installation as outlined in
the Installation Instructions, improper electrical
supply, water supply or drainage; flood, storms, or
other acts of God.
4. Premium labor rates due to holidays, overtime, etc.
Travel time, flat rate service call charges, mileage
and miscellaneous tools and material charges not
listed on the payment schedule are excluded as well
as additional labor charges resulting from inacces-
sibility of the ice machine.
5. Paris or assemblies subjected to misuse, abuse,
neglect or accidents.
6. When the ice machine has been installed, cleaned
and/or maintained inconsistent with the technical
instructions provided in the Owner/Operator Use
and Care Guide and the Installation Manual.
Authorized Warranty Service
To comply with the provisions of the warranty a
refrigeration service company qualified and authorized
by a Manitowoc distributor or a Contracted Service
Representative must perform the warranty repair.
Please contact your local Manitowoc Distributor or
Manitowoc Ice, Inc. for further information regarding
warranty coverage. (NOTE: Have model and serial
numbers of ice machine available when calling. See
Figure 1 for location of model and serial numbers.)
MODEUSERIAL
NUMBERS DECAL |
(ICE MACHINE)
(BIN)
G12SV001
FIGURE 1. MODEL/SERIAL NUMBERS LOCATION
Note: The S/N decal may be on left side of electrical
box.
DIMENSIONS
10.00"
SINGLE REMOTE
OPTIONAL
8.00
34.00"
30.00"
G1200 REMOTE
15.00"
8.25"!
24,25"
Î OPTIONAL
18.00" 12,25"
+ 25.50" 12:00"
A 0.75" Wr DUAL REMOTE
ZZ 250 AA A
> > 5.25"
24.50"
pe Ta
9,25" 23.50" 48.25" <<
39,25"
26.00" 35.25" S
31.25" ®
44,00"
‘| > ` 8.50"
7 > OPTIONAL |
и” > 20.00“
7 > 16.00"
7 . 12.00"
у 8.00"
dd 4.00
» |
“ 6.75%
< 7 >
17.00"
C900 |
> 4.25"
C800
>
C900 BIN-SHOWN G12SV002
FIGURE 2. DIMENSIONS
ELECTRIC SERVICE
SWITCH BOX
1/2" FPT
OUTLET FITTING
(Water-Cooled Models)
34" FPT
BIN DRAIN
FITTING
NOTE: Refer to Remote Installation section for remote condenser line set and electrical connections.
y
WATER CONDENSER EQ
38" FPT
ICE MAKING 18"
WATER INLET
" FPT
WATER CONDENSER
(Water-Cooled Models)
20 PSI MIN./150 PS! A
VENT
y
A
TI
Y
>
UN
U
Um
De
7
VENT
OPEN, TRAPPED
AND VENTED DRAIN
—
TA
3/4" FPT
ICE MAKING
WATER DRAIN
INSULATION SEAL
VALVE
7 WATER
SERVICE
VALVE
ICE MAKING
WATER INLET
20 PSI MIN./80 PSI MAX.
ICE MAKING
WATER DRAIN
4" MIN. 1D.
CONDENSER
WATER DRAIN
(Water-Cooled Models)
1/2" MIN. LD.
G125V003
FIGURE 3. TYPICAL SELF-CONTAINED INSTALLATION
REMOTE
CONDENSER
ELECTRICAL
DISCONNECT
(BY CUSTOMER)
DISCHARGE
LINE
MINIMUM AMOUNT OF
TUBING ABOVE ROOF
LINE
Bore 2.50" diameter hole in roof or wall
for tubing. Seal with tar or pitch and
slope to prevent entrance of moisture.
и ELECTRICAL DISCONNECT (BY CUSTOMER)
<
и”
36.00" Service Loop eu
AN
G125V004
FIGURE 4. TYPICAL REMOTE SINGLE (AC) CONDENSER LINE SET INSTALLATION
DC-1296A
REMOTE TN
CONDENSER ~~ (E ELECTRICAL
SA Va" DISCONNECT
(BY CUSTOMER)
MINIMUM AMOUNT OF
2 TUBING ABOVE ROOF
2 TO SECOND ICE MACHINE
Bore 4.00" diameter hole in roof or wall
for tubing. Seal with tar or pitch and
slope to prevent entrance of moisture. IMPORTANT:
Mark or tag line sets 1 and 2 before running
to prevent crossing of refrigeration systems.
Condenser circuits are labeled 1 and 2.
yg ELECTRICAL DISCONNECT (BY CUSTOMER)
:
>
A
36.00" Service Loop a
\
G125V005
FIGURE 5. TYPICAL REMOTE DUAL (DC) CONDENSER LINE SET INSTALLATION
COMPONENT IDENTIFICATION
1. TERMINAL BOARD 10. RELAY BOARD
2. LOW PRESSURE CONTROL 11. ICE SENSOR MODULE *
3. HIGH PRESSURE CONTROL 12. TRANSFORMER BOARD *
4. TOGGLE SWITCH 13. START RELAY
5. CONTACTOR 14. START CAPACITOR
6. DUMP VALVE TIMER 15. RUN CAPACITOR
7. DELAY TIMER 16. FAN MOTOR CAPACITOR #
8. FUSE, 5 AMP 17. TERMINAL BOARD
9. RELAYS
* MAY BE COMBINED INTO UNITIZED ICE SENSOR BOARD
# AIR-COOLED MACHINES ONLY
G125V006
FIGURE 6. ELECTRICAL CONTROL BOXES
a nao
Oy o
. SIDE COVER (COMPRESSOR
START COMPONENTS BOX)
. FRONT COVER (COMPRESSOR
START COMPONENTS BOX)
. CONTROL BOX COVER
. WATER FLOW CLAMPS
(REGULAR SIZED CUBES ONLY)
. WATER DISCHARGE TUBE
WITH DUMP VALVE)
. SUMP TROUGH
. FLOAT VALVE
. WATER PUMP (WITH BRACKET
AND COVER)
. DRAIN TUBE BRACKET
. WATER CURTAIN
(TWO REQUIRED)
. EVAPORATOR
. LH SUMP TROUGH SUPPORT
. SPLASH SHIELD
. ICE THICKNESS CONTROL
. WATER DISTRIBUTOR TUBE
. BIN SWITCH (TWO REQUIRED)
. SOLENOID DUMP VALVE
(NOT SHOWN)
G125V007
FIGURE 7. EVAPORATOR COMPARTMENT
. AIR-COOLED CONDENSER
. FAN MOTOR
. DRIER
. HIGH AND LOW SIDE
PROCESS VALVES
. COMPRESSOR
BON
On
COON
. RECEIVER
. EXPANSION VALVES
. HOT GAS VALVES
. TOGGLE SWITCH
. FAN CYCLE CONTROL
G12SV008
FIGURE 8. AIR-COOLED COMPRESSOR COMPARTMENT
10
AN +
O1
2
A"
9
ar
de
. CONDENSER WATER DRAIN
. WATER-COOLED CONDENSER
. DRIER
. HIGH AND LOW SIDE PROCESS
VALVES
. COMPRESSOR
o
Y
el
S
LA
=
7
J и
popNo
a
10
A o>
y /%
7
7 `
£ FR
AF Ney 7
. RECEIVER
EXPANSION VALVES
HOT GAS VALVES
TOGGLE SWITCH
. WATER REGULATOR VALVE
G128V009
FIGURE 9. WATER-COOLED COMPRESSOR COMPARTMENT
11
12
e
YE
e fo = —]
NN
— VA/
TAS
Ne A
NR AR
VV
\\
©
/
NY
SUCTION PRESSURE SWITCH
EXPANSION VALVES
TOGGLE SWITCH
HOT GAS VALVES
8
9
10
11
1. RECEIVER
2. SERVICE VALVE
3. LIQUID LINE PUMP
DOWN SOLENOID
-CHECK VALVE
HARVEST PRESSURE
MAGNI
4. DRIER
REGULATING SOLENOID
VALVE
13
PROCESS VALVES
REGULATING VALVE
6. COMPRESSOR
7. HARVEST PRESSURE
5. HIGH AND LOW SIDE
G12SV010
FIGURE 10. REMOTE MACHINE COMPRESSOR COMPARTMENT
12
INTERIOR CLEANING
For efficient operation, clean and sanitize ice machine
every six months.
IMPORTANT
Do not use hot water. If ice machine requires clean-
ing and sanitizing more frequently, consult a
qualified service company to test the water quality
and recommend appropriate water treatment.
Before cleaning, check water dump valve for proper
operation (see Cleaning Water Dump Valve, page 18).
Deposits may accumulate in the valve causing leakage
or restriction of water flow.
REMOVAL OF PARTS FOR
CLEANING
1. Loosen two screws holding front panel in place and
remove front panel.
2. Set ICE/OFF/WATER PUMP switch at OFF after
ice falls from evaporator at completion of harvest
cycle, or set switch at OFF and allow ice to melt off
evaporator.
A CAUTION
Never use any type of object to force ice from
evaporator as damage may result.
3. Turn off water to the ice machine at water service
valve(s).
4. Stacked ice machines: remove ice chutes.
5. Remove all ice from bin.
6. Remove water curtain.
7. Remove drain plug from water trough and allow
water to drain into bin.
REMOVE WATER PUMP (Figure 11)
1. Disconnect water pump power cord.
LOOSEN
SCREWS
© POWER
LL.” CORD
WATER
— PUMP
I
QUTLET
G125V011
FIGURE 11. WATER PUMP REMOVAL
2. Disconnect hose from pump outlet.
3. Remove two screws holding pump mounting brack-
et to rear bulkhead.
4. Lift pump and bracket assembly off screws.
13
REMOVE FLOAT VALVE (Figure 12)
1. Remove wing nuts from bracket and pull bracket
from water trough.
2. Disconnect the water inlet tube from the float valve
at the compression fitting.
3. Remove filter screen and cap.
COMPRESSION WATER
FITTING INLET
TUBE
FILTER
SCREEN AND CAP
REMOVE
WING NUTS
G125V012
FIGURE 12. FLOAT VALVE REMOVAL
REMOVE DISTRIBUTION TUBE
(Figure 13)
1. Remove distribution tube from the two spring clips
holding it in place.
2. Disconnect the hose from the distribution tube.
TOP
SPRING EXTRUSION
CLIPS EN
© LOCATING
‘ PIN
DISTRIBUTION
TUBE
G12SV013
FIGURE 13. DISTRIBUTION TUBE REMOVAL
DISASSEMBLE DISTRIBUTION
TUBE (Figure 14)
NOTE
Disassembly of the distribution tube is not usually
necessary as normal cleaning of the ice machine will
clean the tube. The distribution tube should only be
disassembled if, after normal cleaning procedures,
there is inadequate water flow from the distribution
NOTE
To reinstall distribution tube, align locating pin on top
extrusion with hole in distribution tube.
14
tube.
1. Heat rubber end plugs on distribution tube in warm
water to soften them.
2. Remove end plugs and inner distribution tube.
3. Reheat rubber plugs in warm water after cleaning is
complete and reassemble distribution tube.
END WITHOUT
OLE
RUBBER END
PLUG
RUBBER
END
PLUG
NOTE INNER TUBE
HOLES ARE 180 DEGREES
GA OPPOSITE OUTER TUBE
HOLES
G12SV014
FIGURE 14. DISTRIBUTION TUBE DISASSEMBLY
REMOVE ICE THICKNESS PROBE
(Figure 15)
1. Disconnect wire leads from ice sensor in control
box. Be sure electrical power is disconnected.
2. Compress side of probe at top near hinge pin and
disengage it from the bracket.
@
COMPRESS
EAL
с Le
DISCONNECT
WIRE
LEADS ICE
THICKNESS
CAT PROBE
G12SV015
FIGURE 15. ICE THICKNESS PROBE REMOVAL
REMOVE WATER TROUGH
1. Remove float valve and water pump.
2. Disconnect water outlet hose (Figure 16).
3. Remove thumb screws and remove water trough
(Figure 17).
CLEANING PROCEDURES
Ice Machine Cleaner is for removal of lime scale or other
mineral deposits. It is not used for removal of algae or
slime. Refer to Sanitizing for removal of algae and slime.
G12SV016
FIGURE 16. DISCONNECT WATER OUTLET HOSE
\
A
DÁ WATER
TROUGH
THUMB
SCREWS
G12SV017
FIGURE 17. REMOVE WATER TROUGH
1. Soak parts in a solution of no more than 16 ounces
of cleaner to one gallon of warm water. Use a brush
(DO NOT USE A WIRE BRUSH) or a sponge to
clean the parts, taking care not to damage them.
A caution
Use only Manitowoc Ice Machine Cleaner, Part No.
94-0546-3, in recommended concentration as this is
compatible with materials used in the manufacture
of Manitowoc Ice Machines.
A caution
Do not immerse the water pump motor in the clean-
ing solution. Also, use care when cleaning the ice
thickness probe so as not to move the adjusting
SCrew.
2. Use the cleaning solution and a brush or sponge to
remove scale build-up from the top, sides and bot-
tom extrusions, the inside of the ice machine
panels, and the entire inside of the ice bin.
A dirty top extrusion, Figure 13, could result in
uneven water flow over the evaporator. Ensure all
scale and dirt are removed.
15
3. Thoroughly rinse with clean water all parts and 4. Add four ounces of cleaner to water trough and
surfaces washed with the cleaning solution. allow solutionto circulate a maximum of 10 minutes.
NOTE NOTE
Incomplete rinsing of the ice thickness probe could Use a soft brush on excessively dirty evaporator to
leave residue which could cause the ice machine to help remove deposits. Ensure connecting holes in
go into premature harvest. For best results, brush or back corners of cube molds are open.
wipe off while rinsing and then wipe dry.
5. Set ICE/OFF/ WATER PUMP switch at OFF.
4. Reinstall all parts removed for cleaning except front
panel and top chute (if stacked). 6. Shut off water at float valve. See Figure 12.
CLEANING THE EVAPORATOR 7. Drain water trough by removing drain plug.
NOTE 8. Thoroughly rinse trough with clean water, then
Failure to clean other parts prior to cleaning reinstall drain plug.
evaporator may result in poor cleaning of the
Р у Р 9 9. Turn on water at float valve.
evaporator surface.
10. Set ICE/OFF/ WATER PUMP switch at WATER
1. Turn on water to ice machine at water service valve PUMP and allow water trough to fill to proper operat-
and verify float valve is open, Figure 12. ing level.
2. Allow trough to fill to proper operating level, Figure 11. Sanitize ice machine after cleaning.
52, page 47.
3. Set ICE/OFF/ WATER PUMP switch at WATER
PUMP.
16
SANITIZING
Sanitizer is used for removal of algae or slime AND
AFTER USE OF MANITOWOC ICE MACHINE
CLEANER. It is not used for removal of lime scale or
other mineral deposits.
1. Loosen two screws holding front panel in place and
remove front panel.
2. Set ICE/OFF/ WATER PUMP switch at OFF after
ice falls from evaporator at completion of harvest
cycle or set switch at OFF and allow ice to melt off
evaporator.
A caution
Never use any type of object to force ice from
evaporator as damage may result.
3. Stacked ice machines: Remove ice chute as
described under Removal of Parts for Cleaning,
page 13.
4. Remove water curtain, Figure 55.
10.
11.
Remove all ice from bin.
Set ICE/OFF/ WATER PUMP switch at WATER
PUMP.
Add one ounce of sanitizer to water trough and allow
solution to circulate a minimum of one minute.
Drain solution from trough by removing drain plug,
Figure 52.
Thoroughly rinse trough with clean water, then
reinstall drain plug.
Wash all surfaces requiring sanitizing (ice machine
and bin) with a solution of one ounce of sanitizer to
up to four gallons of water.
Thoroughly rinse all sanitized surfaces with clean
water.
12. Set ICE/OFF/WATER PUMP switch at ICE.
17
CHECKING AND CLEANING
THE WATER DUMP VALVE
OPERATION CHECK
1. Remove front panel.
2. Set ICE/OFF/WATER PUMP switch at ICE.
3. Check clear plastic outlet drain hose of dump valve,
Figure 18, for leakage while the ice machine is in
the freeze cycle.
4. If the dump valve is leaking or restricted, remove,
disassemble and clean.
REMOVE WATER DUMP VALVE
(Figure 18)
A WARNING |
Disconnect electric power to the ice machine at the
electric service switch box.
1. Drain water trough by removing drain plug.
2. Remove two screws from water dump valve mount-
ing bracket.
3. Disconnect wires from dump valve coil.
4. Remove drain hose clamp and carefully remove
both drain hoses from valve.
5. Remove two screws securing dump valve to mount-
ing bracket.
DISASSEMBLE PLASTIC BODY
WATER DUMP VALVE (Figure 19)
1. Lift cap and slide coil retainer cap from top of coil.
2. Lift coil assembly off valve body. Note position of
coil assembly on valve before removing. When
reassembling valve, ensure coil is in same position.
3. Press down on enclosing tube plastic nut and rotate
nut 1/4 turn and remove nut and enclosing tube from
dump valve.
4. Remove enclosing tube, plunger and plastic gasket
from valve body.
BRACKET COIL SHIELD
CREWS
WATER
DRAIN DUMP
HOSES VALVE
G125V018
PLUNGER
SPRING
CAP STOP
PLUNGER
ENCLOSING
TUBE
„
FIGURE 18. WATER DUMP VALVE REMOVAL
18
7 VALVE
BODY
Gesvo19
FIGURE 19. PLASTIC BODY WATER DUMP
VALVE DISASSEMBL Y
DISASSSEMBLE BRASS BODY
WATER DUMP VALVE (Figure 20)
1. Pry off retainer on top of dump valve coil with flat tip
Place spanner tool (Manitowoc Part No. 54-8907-3,
available through your local Manitowoc Distributor)
over enclosing tube and insert pins on spanner tool
into holes on bottom of tube.
Turn spanner tool counterclockwise with 7/8"
wrench and remove enclosing tube, plunger and
rubber gasket from valve body.
CLEANING WATER DUMP VALVE
NOTE
It is not necessary to remove spring from plunger
when cleaning. If spring is removed, insert flared end
of spring into slotted opening in top of plunger until
spring comes in contact with plunger spring stop.
Use care not to stretch or damage spring in plunger
when cleaning.
screwdriver.
© „Еее =
COIL
SPANNER we: он
(Pa Ni No. ~~
day E)
1
| 1 =
ENCLOSING
PLUNGER
SPRING SPRING
STOP
PLUNGER
— O-RING
RUBBER
GASKET
G6SV020
Soak components in cleaning solution (refer to
Cleaning Procedures, page 15). Remove heavy
scale deposits with a stiff-bristle brush. Use a small
bottle brush to clean inside the enclosure tube.
Wipe off rubber gasket with soft cloth.
A caution
Do not soak coil assembly.
FIGURE 20. BRASS BODY WATER DUMP
VALVE DISASSEMBLY
2. Lift coil assembly off valve body. Note position of
coil assembly on valve before removing. When
reassembling valve, ensure coil is in same position.
Thoroughly rinse components with clean water.
Reassemble water dump valve and reinstall in ice
machine.
19
ELECTRICAL
SEQUENCE OF OPERATION
SELF-CONTAINED AIR OR WATER COOLED
FREEZE CYCLE
(Prechill of Evaporator/Water Dump)
With the toggle switch in the ice position, the current will
flow through the high pressure cut-out and rear and front
bin switches energizing the contactor coil. With the
contactor energized the compressor will start. Voltage
through the contactor and normally closed (n.c.) 7-
second delay timer switch. The current flow through
normally closed ice sensor relay contact #5 energizes
is supplied through the primary of the transformer,
the fan motor, water pump, dump valve and dump valve
timer. Water flows through the energized dump valve
and down the drain. This prechills the evaporators while
water is flushed from the sump trough.
2
START RELAY
CONPRESSOR
208-230 V, 1 Ph, 50/60 Hz
CRAMK—CASE HEATER
Hi PRESS
CUTOUT
BOLD LINES (—) SHOW CIRCUIT DURING PRECHILL OF EVAPORATOR.
7-SECOND DELAY TINER
2
SV1064
FIGURE 21. PRECHILL ELECTRICAL SEQUENCE
Prechill Electrical Sequence
1. Toggle switch ................. ice position 1. Fan motor (may cycle on/off
2. Highpressurecutout ............... closed on fan cycle control) ........ energized
3. Rearbinswitch .................... closed 2. Waterpump .............. energized
4. Frontbinswitch .................... closed 3. Dump valve timer .......... energized
5. Contactor ..................... energized Timerswitch ................ closed
6. Compressor .................. energized 4. Dump valve solenoid ....... energized
7. 7-seconddelaytimer.......... not energized C. Ice sensorrelay contact#6 ......... open
Timer switch ............ ...... .... closed 10. Harvest relays A, B, C
8. Power at transformer primary ........... yes А. Relay A ................. not energized
9. icesensorrelay .............. not energized Front hot gas valve ....... not energized
A. lce sensor relay contact 43 ......... open В. RelayB ................. not energized
В. Ice sensorrelay contact #5 ...... closed Rear hot gas valve ........ not energized
C. RelayC ................. not energized
20
switch will de-energize the dump valve and water will
begin to flow over the evaporators, forming ice. The
freeze cycle will last approximately 10-15 minutes,
depending on air and water temperatures entering the
ice machine. (Refer to Cycle Time Chart, page 64.)
FREEZE CYCLE
(Self-Contained Air or Water Cooled)
The normally closed (n.c.) dump valve timer switch will
open after the dump valve timer is energized continually
for 20 seconds. The opening of the dump valve timer
/
208-230 V, 1 Ph, 50/60 Hz
CRANK-CASE HEATER
7=SECOND DELAY TINER
USE 5 AMP HTH
(ON RELAY BOARD)
2
START RELAY
COMPRESSOR
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
SV1065
FIGURE 22. FREEZE CYCLE ELECTRICAL SEQUENCE
Freeze Cycle Electrical Sequence
1. Toggleswitch ................. ice position 1. Fan motor (may cycle on/off
2. Highpressurecutout ............... closed on fan cycle control) ...... energized
3. Rearbinswitch .................... closed 2. Waterpump .............. energized
4. Frontbinswitch .................... closed 3. Dump valve timer .......... energized
5. Contactor ..................... energized Timerswitch .................. open
6. Compressor ..............cc.... energized 4. Dump valve solenoid ....not energized
7. 7-seconddelaytimer.......... not energized C. Icesensorrelaycontact#6 ......... open
Timerswitch ...................... closed 10. Harvest relays A, B, C
8. Power at transformerprimary ........... yes A. RelayA ................. not energized
9. Icesensorrelay .............. not energized Fronthotgasvalve ....... not energized
A. ice sensor relay contact 43 ......... open B. RelayB ................. not energized
В. Ice sensorrelay contact#5...... closed Rear hot gas valve ........ not energized
С. RelayC ................. not energized
21
HARVEST CYCLE (NO. 1)
(Self-Contained Air or Water Cooled)
(ice on Both Evaporators)
The harvest cycle begins when water flowing over the
ice on the evaporator contacts the probes on the ice
thickness control. After a constant 6-10 seconds of
water contact, the relay on the ice sensor board is
energized, changing contacts #3, #5 and #6.
Contact #3 — Closes to supply a secondary power to
the contactor during the entire harvest cycle. Power is
needed to prevent the contactor from de-energizing, as
the power supply through the bin switches to the
contactor will be interrupted as the bin switches open
momentarily during the harvest cycle.
Contact #5 — Opens to de-energize the condenser
fan motor, water pump and dump valve timer.
Contact #6 — Closes to energize the front hot gas valve,
rear hot gas valve, and relay C. Relay C closed two sets
of contacts.
NOTE
Relay C is used to isolate components from voltage
supply during the automatic shut-off mode, thus has
no specific function while the ice machine is running.
USE 5 AMP MTH Hi PRESS
(OM RELAY BOARD) CUTOUT
208-230 V, 1 Ph, 50/60 Hz
7=-SECOND DELAY TIMER 40
В
Ie à?
O
nl
NC SER SMICH 40
=
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
SV1066
FIGURE 23. HARVEST CYCLE ELECTRICAL SEQUENCE
Harvest Cycle Electrical Sequence
1. Toggleswitch ................. ice position 1. Fan motor ........... not energized
2. High pressure cut-out ............... closed 2. Water pump ........... not energized
3. Rearbinswitch .................... closed 3. Dump valve timer .......not energized
4. Frontbinswitch.................... closed Timerswitch ................ closed
5. Contactor ..................... energized 4. Dump valve solenoid ....not energized
6. Compressor ................... energized C. ice sensor relay contact 46 ....... closed
7. T7-second delay timer .......... not energized 10. Harvest relays A, B, C
Timerswitch ...................... closed A. RelayA ................. not energized
8. Power attransformerprimary ........... yes Fronthotgasvalve .......... energized
9. Icesensorrelay ................. energized В. RelayB ................. not energized
A. Ice sensor relay contact #3 ........ closed Rear hot gas valve ........... energized
В. Ice sensor relay contact 45 ........ open С. RelayC ................... ..energized
22
HARVEST CYCLE (NO. 2)
(Self-Contained Air or Water Cooled)
(Ice Falling off Front Evaporator,
Tripping Front Bin Switch/
Ice on Rear Evaporator)
During the harvest mode, the hot gas raises the
evaporator temperatures, causing the release of the ice
from the evaporators. The ice may drop from the front,
Figure 24, or rear, Figure 25, in any order or at the same
time.
Figure 24 shows the ice as it is falling off the front
evaporator (before the rear), pushing out on the front
water curtain. The front water curtain movement will
momentarily change the front bin switch from the
normally closed (n.c.) position to the normally open
(n.o.) position. The bin switch movement to the open
position will energize the relay À coil.
The normally closed (n.c.) contact of relay A will open
and de-energize the front hot gas valve. Both normally
open (n.o.) contacts of relay A will close. One of the
n.o. contacts closes, acting as a holding circuit to keep
relay A coil energized. This is required because the
power supply to relay A coil is lost through the bin
switch after ice falls into the bin and the water curtain
falls back toward the evaporator.
The normally open (n.o.) contact of relay A, in series
with the 7-second delay timer, closes. Timer will not
energize until both normally open (n.o.) contacts of relay
A and B are closed.
KO)
USE 5 AMP MTH HI PRESS
(ON RELAY BOARD) TOUT
208-230 V, 1 Ph, 50/60 Hz
7-SECOND DELAY TMER +
REL A REL E
3 2
47 |
Ln
START RELAY
|| —N.C. SCR SWITCH 40
а
1 al
LED =
@— roro 319
Pa [
oe NTTTTTV- 2 Luna
ICE 20 TRANSFORMER
T — № KE
5 ENERGZED | > NN, MHICKNESS FAN MOTOR
: CONTROL {AR COOLED ONLY) |
AS FAN CYCLE CONTROL \ 4 |
| (NR COOLED ONLY)
INC, SCR SWITCH
(À, DUP VALVE SOLENOID |
CO “|
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
SV1067
FIGURE 24. HARVEST CYCLE ELECTRICAL SEQUENCE
23
HARVEST CYCLE (NO. 3)
(Self-Contained Air or Water Cooled)
(ice from Front Evaporator in Bin/
Ice on Evaporator Falling off,
Tripping Rear Bin Switch)
During the harvest mode, the hot gas raises the
evaporator temperatures, causing the release of the ice
from the evaporators. The ice may drop from the front,
Figure 24, or rear, Figure 25, in any order or at the same
time.
Figure 25 shows the ice as it is falling off the rear
evaporator (after ice has fallen off the front), pushing out
on the rear water curtain. The rear water curtain movement
will momentarily change the rear bin switch from the
normally closed (n.c.) position to the open position.
The rear bin switch movement to the open position will
energize the relay B coil. The normally closed (n.c.)
contact of relay B will open and de-energize the rear hot
gas valve. Both normally open (n.o) contacts of relay
B will close. One of the n.o. contacts will close, acting as
a holding circuit to energize relay B coil. This is required
because the power supply to relay coil B is lost after
ice falls into the bin and the water curtain falls back
toward the evaporator. The other normally open (n.o.)
contact closes to energize the 7-second delay timer.
u
208-230 V, 1 Ph, 50/60 Hz
CRANK—CASE HEATER
© 7-SECOND DELAY TIMER 40
= REL A REL B
à LE na iy в. ya? г
hen Al _ Al 18 _ M 40
NO NO 1} Ne SAS TCH
1
LED
NO
A rms 7 2 HOT GAS SOL
Lao J й Ey 7
ei i
NO ва. с NC
x J A mmm PL с "E
16 HOT GAS SOL
e" 13 23 (CN FRONT
д REL A
18 HO NO REL A 19
с
JM Rae; о CONTACTOR COL
NC NC 27 7 49
— > E 12V 12V
28 29 FRONT EIN
START RELAY SMTCH —_ | | |
8 3 Le
`` £
`` Tm . |
COMPRESSOR г г Ju 2
ICE 20
< da
Ca
5 ENERGIZED Г № Нее FAN MOTOR
3 2 TROL (AR COOLED ONLY)
>» Fr N X "FAN COLE
WATER (AR COOLED ONLY)
pue Led ne
SOR SMTCH
N DUMP VALVE EN DUMP VALVE SCUENOD |
me NZ =]
L 40 | 40 40 40
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
SV1069
FIGURE 25. HARVEST CYCLE ELECTRICAL SEQUENCE
24
HARVEST CYCLE (NO.4)
(Self-Contained Air or Water Cooled)
(ice from Both Evaporators Has
Fallen into Bin)
Relays A and B are both energized after ice falls off both
After the timer is "energized" continually for 7 seconds,
the timer switch will open. This interrupts the primary
power supply at the transformer, de-energizing the ice
sensor relay on the unitized board. The ice sensor relay
contacts #3, #5, and #6 change position. The ice
evaporators. With the normally open (n.o.) contacts of
relays A and B closed, the 7-second delay timer relay is
machine will cycle back into the freeze cycle prechill.
energized.
208-230 V, 1 Ph, 50,60 Hz
ee CRANK~CASE HEATER
© HI PRESS VWVE 7-SECOND DELAY TIMER © |
x USE 5 AMP MH 7
= CUTOUT REL A
cont AO (ON RELAY BOARD) 491 57 as 2 UY 1% Te — J 2 {
_ ACTOR я 5 _ ? LN ve fn No 18 |! —N.C. SER SMITCH 40
2
L zZ = '
START a ss 16 NO are BL A
ACTOR LS Nd
as + re HOT GAS SOL
— ac MT || 17 2, (E rn 1]
58 D] CENTER OF CRAM N—
REL C NC
WATER PUMP NO Y
5 al. Deren 1
50 Xx 7
aa a Y 16 NL: 3 > MOT Gas 50L
hore oye у. _
TOGGLE SWITCH as | iy No NO REL A | 19
с
Y wol REL € 7 CONTACTOR COI.
[ $ 24 236 NO a 42
2 1 с 27 ne |
5 N zu SN MU € É ©
Us 2 REAR BIN 28 и 29 FRONT EN 12V 12V
START RELAY Swe в -_— LL
3] ad
| À
COMPRESSOR = > ты = > LLL e 2
Г ( ode = 2 TRANSFORMER
5 ENERGIZED TT \ THES FAN NOTOR
pure 7 | (AR COOLED ONLY)
- FAN CYCLE CONTROL
wur | | 1 = (AR COOLED ONLY)
LES Ne str swrcH
DUMP VALVE DUMP VALVE SOLENOID
X A VA o
Xu, “|
| | 46 40 49
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE. SV1070
FIGURE 26. HARVEST CYCLE ELECTRICAL SEQUENCE
Harvest Cycle Electrical Sequence
(Switch positions shown just after ice has fallen off both evaporators and the 7-second delay timer is energized.)
1. Toggleswitch ................. ice position
2. High pressure cut-out ............... closed
3. Rearbinswitch .................... closed
4. Frontbinswitch .................... closed
5 Contactor ..................... energized
6. Compressor ................... energized
7. 7-second delay timer ............. energized
Timerswitch ...................... closed
(will open in 7 seconds)
8. Power at transformerprimary ........... yes
9. Icesensorrelay ................. energized
A. Ice sensor relay contact #3 ........ closed
В. Ice sensor relay contact #5 ........ open
C.
10. H
A
d
B.
C.
1. Fan motor
2. Water pump ...........
3. Dump valve timer
not energized
not energized
not energized
Timerswitch ................ closed
4. Dump valve solenoid ....not energized
Ice sensor relay contact #6 ....... closed
rvest relays A, B, C
Ве!ау А... ................. energized
Front hot gas valve ....... not energized
RelayB .................... energized
Rear hot gas valve ........ not energized
RelayC .................... energized
25
AUTOMATIC SHUT-OFF
(Self-Contained Air or Water Cooled)
(Full Bin of Ice)
(ice from Front Evaporator in Bin/
Ice from Rear Evaporator Holding
Rear Curtain Open)
When ice storage bin becomes full, the last harvesting
of ice cubes will not completely clear either the front or
rear water curtain, holding it open. This will shut the ice
machine off when it cycles back into the freeze mode.
In the example below, ice has fallen off the front
evaporator and cleared the front water curtain. This may
have occurred before or after ice falls off the rear evaporator.
The ice fell from the rear evaporator and did not
completely clear the water curtain. This holds the rear
bin switch in the open position.
At this point the main power supply through the bin
switches to the contactor is lost. The contactor is being
energized through ice sensor contact #3 which is closed
during the harvest cycle only. (The ice machine will not
shut off until a complete harvest cycle occurs). As the
ice machine cycles back into the freeze cycle, the ice
sensor contact #3 will open. The contactor will
de-energize and the ice machine shuts off. The ice
machine remains off until sufficient ice is removed from
the bin allowing ice to clear the water curtain and close
the bin switch. |
NOTE
Relay C prevents the front hot gas valve from ener-
gizing when the ice machine is shut off on a rear bin
switch.
START RAY
COMPRESSOR
208-230 V, 1 Ph, 50/60 Hz
CRANK-CASE HEATER
BOLD LINES (—) SHOW CIRCUIT DURING AUTOMATIC SHUT-OFF — FULL BIN OF ICE.
SV1071
FIGURE 27. AUTOMATIC SHUT-OFF ELECTRICAL SEQUENCE
Automatic Shut-Off Electrical Sequence
1. Toggle switch ................. ice position 1. Fan motor ........... not energized
2. High pressure cut-out ............... closed 2. Water pump ........... not energized
3. Rearbinswitch ..................... open 3. Dump valve timer ....... not energized
4. Frontbinswitch .................... closed Timerswitch ................ closed
5. Contactor .................. not energized 4. Dump valve solenoid ....not energized
6. Compressor .......... SA not energized C. Ice sensor relay contact #6 ......... open
7. 7-seconddelaytimer.......... not energized 10. Harvest relays A, B, C
Timerswitch ...................... closed A. RelayA ................. not energized
8. Power attransformer primary ............ no Front hot gas valve ....... not energized
9. lIcesensorrelay ............e. not energized В. RelayB ................. not energized
A. lce sensor relay contact 43 ......... open Rear hot gas valve ........ not energized
В. Ice sensor relay contact #5 ...... closed С. Ве!ау С ................. not energized
26
ELECTRICAL
SEQUENCE OF OPERATION
REMOTE ICE MACHINES
FREEZE CYCLE
(Prechill of Evaporator/Water Dump)
Initial Start-Up
With the toggle switch in the ice position, current wil flow
through the rear and front bin switches to energize the
liquid line solenoid. The low pressure will rise, closing
the low pressure cut-out (approximately 40 psig) to
energize the contactor coil which starts the compressor
and the prechill.
Freeze Cycle Prechill
Voltage is supplied to the primary of the transformer
through the contactor, normally closed (n.c.) switch of
the 7-second delay timer and the harvest pressure limit
cut-out. The current flow through normally closed (n.c.)
ice sensor relay contact #5 energizes the remote
condenser, fan motor, water pump, dump valve, and
dump valve timer. Water flows through the energized
dump valve and down the drain. This prechills the
evaporators while water is flushed from the sump
trough.
BOLD LINES (—) SHOW CIRCUIT DURING PRECHILL OF EVAPORATOR.
208-230 V, 1 Ph, 50/60 Hz
SV1072
FIGURE 28. PRECHILL ELECTRICAL SEQUENCE
Prechill Electrical Sequence
1. Toggleswitch ................. ice position 1. Remote condenser
2. Rearbinswitch .................... closed fan motor ............... energized
3. Frontbinswitch .................... closed 2. Waterpump .............. energized
4. Liquid line solenoid valve ......... energized 3. Dump valve timer .......... energized
5. High pressure cut-out ............... closed Timer switch ................ closed
6. Low pressure cut-out ............... closed 4. Dump valve solenoid ....... energized
7. Contactor ..........oeeccem een. energized С. Ice sensor relay contact #6 ......... open
8. Compressor .....0.0.0.0.0.0000000004 energized D. Harvest pressure regulating
9. 7-seconddelaytimer.......... not energized (HPR) solenoid ........... not energized
Timer switch ...................... closed 13. Harvest relays A, B, C
10. Harvest pressure limiter ............. closed A. RelayA ................. not energized
11. Power at transformer primary ........... yes Fronthotgasvalve ....... not energized
12. Ice sensor relay .............. not energized. В. RelayB ................. not energized
A. lcesensorrelaycontact#3......... open Rearhotgasvalve ........ not energized
В. Ice sensor relay contact #5 ...... closed C. RelayC ................. not energized
27
FREEZE CYCLE
(Remote Machines)
The normally closed (n.c.) dump valve timer switch will
open after the dump valve timer is energized continually
switch will de-energize the dump valve and water will
begin to flow over the evaporators, forming ice. The
freeze cycle will last approximately 10-16 minutes,
for 20 seconds. The opening of the dump valve timer
depending on air and water temperatures entering the
ice machine. (Refer to Cycle Time Chart, page 64.)
208-230 V, 1 Ph, 50/60 Hz
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
LATER Sw
SV1073
FIGURE 29. FREEZE CYCLE ELECTRICAL SEQUENCE
Freeze Cycle Electrical Sequence
1. Toggleswitch ................. ice position 1. Remote condenser
2. Rearbinswitch .................... closed fanmotor ............... energized
3. Frontbinswitch.................... closed 2. Water pump .............. energized
4. Liquid line solenoid valve ......... energized 3. Dump valve timer .......... energized
5. High pressure cut-out ............... closed Timerswitch .................. open
6. Lowpressurecutout ............... closed 4. Dump valve solenoid ....not energized
7. Contactor ..................... energized С. Ice sensor relay contact #6 ......... open
8. Compressor ................... energized D. Harvest pressure regulating
9. 7-seconddelaytimer.......... not energized (HPR) solenoid ........... not energized
Timerswitch ...................... closed 13. Harvest relays A, B, C
10. Harvest pressure limiter ............. closed A. RelayA ................. not energized
11. Power at transformer primary ........... yes Front hot gas valve ....... not energized
12. Ice sensor relay .............. not energized В. RelayB ................. not energized
А. ice sensor relay contact 43 ......... open Rear hot gas valve ........ not energized
В. ice sensor relay contact +5 ...... closed С. RelayC................. not energized
28
>
HARVEST CYCLE (NO. 1)
(Remote Machines)
(Ice on Front and Rear Evaporators)
The harvest cycle begins when water flowing over the
ice on the front evaporator contacts the probes on the
ice thickness control. After a constant 6-10 seconds of
water contact, the relay on the ice sensor board is
energized, changing contacts #3, #5 and #6.
Contact #3 — Closes to supply a secondary power to
the liquid line solenoid during the entire harvest cycle.
This is needed to prevent the liquid line solenoid from
de-energizing, as the power supply through the bin
switches to the liquid line solenoid will be interrupted as
the bin switches open momentarily during the harvest
cycle.
Contact #5 — Opens to de-energize the remote con-
denser fan motor, water pump and dump valve timer.
Contact #6 — Closes to energize the front hot gas valve,
rear hot gas valve, harvest pressure regulating (HPR)
valve, and relay C. Relay C closed two sets of contacts.
NOTE
Relay C is used to isolate components from voltage
supply during the automatic shut-off mode, thus has
no specific function while the ice machine is running.
208-230 V 1Ph
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
50/60 Hz
SV1074
FIGURE 30. HARVEST CYCLE ELECTRICAL SEQUENCE
Harvest Cycle Electrical Sequence
1. Toggle switch ................. ice position 1. Remote condenser
2. Rearbinswitch .................... closed fan motor ............ not energized
3. Frontbinswitch .................... closed 2. Water pump ........... not energized
4. Liquid line solenoid valve ......... energized 3. Dump valve timer ....... not energized
5. High pressure cut-out ............... closed Timerswitch ................ closed
6. Lowpressurecut-out ............... closed 4. Dump valve solenoid ....not energized
7. Contactor ..................... energized C. Ice sensor relay contact #6 ....... closed
8. Compressor ................... energized D. Harvest pressure regulating
9. 7-seconddelaytimer.......... not energized (HPR) solenoid .............. energized
Timerswitch ...................... closed 13. Harvest relays A, B, C
10. Harvest pressure limiter ............. closed A. RelayA ................. not energized
11. Power at transformer primary ........... yes Fronthotgasvalve .......... energized
12. Ice sensor relay ................. energized В. RelayB ................. not energized
A. lce sensor relay contact 43 ........ closed Rear hot gas valve ........... energized
В. Ice sensor relay contact 45 ........ open C. RelayC .................... energized
29
HARVEST CYCLE (NO. 2)
(Remote Machines)
(ice Falling off Front Evaporator,
Tripping Front Bin Switch/
Ice on Rear Evaporator)
During the harvest mode, the hot gas raises the
evaporator temperatures, thus causing the release of
the ice from the evaporators. The ice may drop from the
front, Figure 31, or the rear, Figure 32, in any order, or
at the same time.
Figure 31 shows the ice as it is falling off the front
evaporator (before the rear), pushing out on the front
water curtain. The front water curtain movement will
momentarily change the front bin switch from the
normally closed (n.c.) position to the open position.
The bin switch movement to the open position will
energize the relay A coil.
The normally closed (n.c.) contact or relay A will open
and de-energize the front hot gas valve. Both normally
open (n.o.) contacts of relay A will close. One of the
n.o. contacts closes, acting as a holding circuit to keep
relay A coil energized. This is needed because the
power supply to relay A coil is lost through the bin
switch after ice falls into the bin and the water curtain
falls back toward the evaporator.
The other normally open (n.o.) contact of relay A, in
series with the 7-second delay timer, closes. The
7-second delay timer will not energize until both
normally open (n.o.) contacts of relay A and B are
closed.
208-230 V 1Ph 50/60 Hz
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
CRANK-CASE HEATER
az 42
7- SEC DELAY TIMER HARY PRESS
LAITER SW
SV1075
FIGURE 31. HARVEST CYCLE ELECTRICAL SEQUENCE
30
HARVEST CYCLE (NO. 3)
(Remote Machines)
(ice from Front Evaporator in Bin/
Ice on Rear Evaporator Falling off,
Tripping Rear Bin Switch)
During the harvest mode, the hot gas raises the
evaporator temperatures, causing the release of the ice
from the evaporators. The ice may drop from the front,
Figure 31, or the rear, Figure 32, in any order or at the
same time.
Figure 32 shows the ice as it is falling off the rear
evaporator (after ice has fallen off the front), pushing out
on the rear water curtain. The rear water curtain
movement will momentarily change the rear bin switch
from the normally closed (n.c.) position to the open
position. The rear bin switch movement to the n.o.
position will energize the relay B coil. The normally
closed (n.c.) contact of relay B will open and de-energize
the rear hot gas valve. Both normally open (n.o.)
contacts of relay B will close. One of the n.o. contacts
closes, acting as a holding circuit to keep relay B coil
energized. This is needed because the power supply
to relay B coil is lost through the rear bin switch after ice
falls into the bin and the water curtain falls back toward
the evaporator.
The other normaily open (n.o.) contact of relay B closes
to energize the 7-second delay timer.
208-230 V
1Ph 50/60 Hz
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
CHANC-CASE HEATER
SV1077
FIGURE 32. HARVEST CYCLE ELECTRICAL SEQUENCE
31
HARVEST CYCLE (NO. 4)
(Remote Machines)
(Тсе from Both Evaporators Has
Fallen into Bin)
Relays A and B are both energized after ice falls off both
evaporators. With the normally open (n.o.) contacts
of relays A and B closed, the 7-second delay relay is
energized. After the timer is "energized" continually for
7 seconds, the timer switch will open. This interrupts the
primary power supply at the transformer, de-energiz-
ing the ice sensor relay on the unitized board. The ice
sensor relay contacts #3, #5, and #6 change position.
The ice machine will cycle back into the freeze cycle
prechill.
| mi то === = —= == == == == —
208-230 V 1Ph 50/60 Hz
BOLD LINES (—) SHOW CIRCUIT DURING HARVEST CYCLE.
СЯАНК-САЗЕ HEATER
62 42
7-SEC DELAY TIMER
HARY PRESS
LATER SW
SV1078
FIGURE 33. HARVEST CYCLE ELECTRICAL SEQUENCE
Harvest Cycle Electrical Sequence
(Switch positions shown just after ice has fallen off both evaporators and the 7-second delay timer is energized.)
32
1. Toggleswitch ................. ice position
2. Rearbinswitch .................... closed
3. Frontbinswitch .................... closed
4. Liquid line solenoid valve ......... energized
5. High pressure cut-out ............... closed
6. Lowpressurecutout ............... closed
7. Contactor ..................... energized
8. Compressor ............eeeo ee. energized
9. 7-second delay timer ....... PO energized
Timerswitch ...................... closed
(will open in 7 seconds)
10. Harvest pressure limiter ............. closed
11. Power at transformer primary ........... yes
12. Ice sensor relay ................. energized
A. lce sensor relay contact 43 ........ closed
В. Ice sensor relay contact 45 ........ open
C.
D.
13. H
A
a
B.
C.
1. Remote condenser
fan motor
not energized
2. Water pump ........... not energized
3. Dump valve timer ....... not energized
Timer switch ................ closed
4. Dump valve solenoid ....notenergized
Ice sensor relay contact #6 ....... closed
Harvest pressure regulating
(HPR) solenoid .............. energized
rvest relays A, B, C
Ве!ау А .................... energized
Fronthotgasvalve ....... not energized
RelayB .................... energized
Rear hot gas valve ........ not energized
RelayC .................... energized
AUTOMATIC SHUT-OFF
(Remote Machines)
(Full Bin of Ice)
(Ice from Front Evaporator in Bin/
Ice from Rear Evaporator Holding
Rear Curtain Open)
When the ice storage bin becomes full, the last
harvesting of ice cubes will not completely clear either
the front or rear water curtain, holding it open. This will
shut the ice machine off when it cycles back into the
freeze mode. In this example, ice has fallen off the front
evaporator and cleared the front water curtain. This may
have occurred before or after ice falls off the rear
evaporator. The ice fell from the rear evaporator and did
not completely clear the water curtain. This holds the
rear bin switch in the open position.
At this point the main power supply through the bin
switches to the liquid line solenoid is lost. The liquid
line solenoid is being energized through ice sensor
contact #3 which is closed during the harvest cycle only.
(The ice machine will not shut off until a complete
harvest cycle occurs.) As the ice machine cycles back
into the freeze cycle, the ice sensor contact #3 will open.
The liquid line solenoid will de-energize. The compressor
will continue to run and pump down the low side of the
ice machine. When the suction pressure reaches ap-
proximately 15 psig, the low pressure cut-out control
opens and de-energizes the contactor, shutting the ice
machine off.
NOTE
Relay C prevents the front hot gas valve and HPR
valve from energizing when the machine is shut off
by a rear bin switch.
The ice machine remains off until sufficient ice is
removed from the bin allowing ice to clear the water
curtain and close the bin switch.
PRESS CONTACTOS “a
curt Lo Press CUTOU con “
- 5 al = er va" 1
7=5£C DELAY THER ная PRESS
= Da 71 TU SE
12 1 т ! “A
REL ma H
MEL в a A
10 Dar я HG SR SmTCH
hd
ко в HOT CAS SOL
ве had = RCAR
CONTR CF |
MATER PAP =, у ©
Ch PN
| MC HPA
LT Hey
| epee 1 23
MOT CAS AOL
MEL A FONT
[E] CA IF at т Gm —— |
MLC REL A
“ mir
= 3) каг вн
E "E Mu € | STO
Rat Bn 28 =
Sart Lou ©
2 SELENCIO \ A
, Ll [ 1
x ny nm T IVETE
Г Ё # seo tE KI *
; a nales
Dun VALVE TER y соч Г. Fang OnE
WATER 3 2 р
ae PE 127 174
1
pa vi +
| © Las = 43 AC SOR SWICH 4 I
BOLD LINES (—) SHOW CIRCUIT DURING AUTO SHUT-OFF CYCLE.
fr
SV1079
FIGURE 34. AUTOMATIC SHUT-OFF ELECTRICAL SEQUENCE
Automatic Shut-Off Electrical Sequence
1. Toggleswitch ................. ice position
2. Rearbin switch ..................... open
3. Frontbinswitch .................... closed
4. Liquid line solenoid valve ...... not energized
5. High pressure cut-out ............... closed
6. Lowpressurecut-out ................ open
7. Contactor .................. not energized
8. Compressor ................ not energized
9. 7-second delay timer .......... not energized
Timer switch .........eemceccaroeaco closed
10. Harvest pressure limiter ............. closed
11. Power at transformer primary ............ no
12. Ice sensor relay
A. ice sensor relay contact #3
B. Ice sensor relay contact #5
open
1. Remote condenser
fan motor ............ not energized
2. Water pump ........... not energized
3. Dump valve timer ....... not energized
Timerswitch ................ closed
4. Dump valve solenoid . ...not energized
C. lce sensor relay contact 46 ......... open
D. Harvest pressure regulating
(HPR) solenoid ........... not energized
13. Harvest relays A, B, C
A. RelayA ................. not energized
Front hotgas valve ....... not energized
В. RelayB ................. not energized
Rear hot gas valve ........ not energized
С. RelayC ................. not energized
33
3-PHASE WIRING DIAGRAMS
(208/230 V, 3 Ph, 50/60 Hz)
208-230 V, 3 Ph, 50/60 Hz
CRANK-CASE HEATER
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
SV1050
FIGURE 35. SELF-CONTAINED AIR OR WATER COOLED WIRING DIAGRAM
208-230 V, 3 Ph, 50/60 Hz
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
SV1051
34
FIGURE 36. REMOTE MACHINES WIRING DIAGRAM
3-PHASE WIRING DIAGRAMS
(380/220 V, 3 Ph, 50 Hz)
380-220 V, 3Ph, 50 Hz
CRAMK—CASE HÉATER
Hi PRESS
с
но
LAT BOARD)
FUSE
9 TOGGLE
(ON RELAY BOARD) 16 NC 2 с
33 52 REL À
5 15
c REL €
NO CONTACTOR COL
24 250 no 42
с
26 NC с
174 12V
REAR EN 28 27 FRONT EN
2
TRANSFORMER
(AR
DUMP VALVE
TIMER
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
SV1052
FIGURE 37. SELF-CONTAINED AIR OR WATER COOLED WIRING DIAGRAM
380-220 V, 3 Ph, 50 Hz
Pod |
I |
| |
| | FUSE 5 AUP NTH
] | (OM RELAY BOARD) “5 4
| | fel:
i I 3 ls
I | 5 50
| | TOGGLE SWITCH
| ] we
EJ |
BOLD LINES (—) SHOW CIRCUIT DURING FREEZE CYCLE.
SV1053
FIGURE 38. REMOTE MACHINES WIRING DIAGRAM
35
WATER SYSTEM
SEQUENCE OF OPERATION
SELF-CONTAINED OR REMOTE MACHINES
WATER SYSTEM
REAR
EVAPORATOR
FRONT
EVAPORATOR
WATER INLET
DUMP WATER WATER
SUPPLY
FLOAT
VALVE
—~ _ OVERFLOW
TO TUBE —
DRAIN
SV1103
FIGURE 39. PRECHILL WATER FLOW
SEQUENCE
Prechill Water Flow Sequence
The water from the sump trough is pumped through the
energized dump valve and down the drain. The flushing
helps to keep the cubes clear and reduces the
frequency of the ice machine cleanings.
REAR
EVAPORATOR
FRONT
EVAPORATOR
WATER INLET |
VALVE \æ PUMP SUPPLY
|
A о
FLOAT
| Ци” VALVE
i
=] OVERFLOW ЕЕ
TO N TUBE == 4
DRAIN —
SV1107
FIGURE 41. HARVEST CYCLE WATER
FLOW SEQUENCE
36
REAR
EVAPORATOR
FRONT
EVAPORATOR
WATER INLET
DUMP WATER WATER
VALVE PUMP SUPPLY
Г
m Ï 0
FLOAT
VALVE
|
OVERFLOW —
TO TUBE
DRAIN
SV1106
FIGURE 40. FREEZE CYCLE WATER
FLOW SEQUENCE
Freeze Cycle Water Flow Sequence
Water from the sump trough is pumped to the
distribution tubes above the evaporators. The float valve
maintains proper water level in the sump trough.
Harvest Cycle Water Flow Sequence
The water pump does not operate during the harvest
cycle. Some water may run out overflow tube and down
drain.
REFRIGERATION SYSTEM
SEQUENCE OF OPERATION
SELF-CONTAINED AIR OR WATER COOLED
PRECHILL AND FREEZE CYCLE
SAAR AN NENE
С
НЕАТ FRONT
EXCHANGE EVAPORATOR
EXPANSION
VALVE
CPP PL TIPPS IIIS III IIIT
SUCTION LINE
EVAPORATOR
ur A
HOT GAS
SOLENOID VALVES
REAR
EVAPORATOR
A SSI
| (FI > |
RECEIVER
ESJHIGH PRESSURE VAPOR HIGH PRESSURE LIQUID NSLOW PRESSURE LIQUID RYLOW PRESSURE VAPOR SV1094
FIGURE 42. PRECHILL AND FREEZE CYCLE SEQUENCE
Prechill Refrigeration Sequence
There is no water flow over the evaporator during the FREEZE CYCLE PRESSURES
prechill. The refrigerant absorbs heat (picked up during Ambient Head Suction
the harvest cycle) from the evaporators. The suction Temp. Pressure Pressure
pressure decreases during prechill. oF PSIG PSIG
Freeze Cycle Refrigeration Sequence Air Cooled
The refrigerant is absorbing heat from water running 50 175-225 38-24
over the evaporator surface. The suction pressure 70 175-225 40-26
gradually drops as ice forms. 80 220-250 42-27
90 250-270 44-28
100 275-325 46-30
Water Cooled
50 225-235 38-24
70 225-235 38-24
80 225-235 — 38-24
90 225-235 40-24
100 225-235 44-24
37
HARVEST CYCLE
(Self-Contained or Water Cooled)
ANNO
N N
N N
N
N
N HEAT FRONT N REAR
\ EXCHANGE EVAPORATOR N EVAPORATOR
| PASSES NN ES EE" )
N Ns —< CEI
N CUENTO CO 1
\ <= > € >
N (A !
N — EXPANSION , EXPANSION SN)!
N VALVE VALVE —
N OSEA TEE SUEZ EE
N
\
N HOT GAS
N SOLENOID VALVESA Ei
N SUCTION LINE E
I XX, EVAPORATOR
| N
Г \
\ COMPRESSOR тт
N
NS AIR/WATER COOLED
CONDENSER
DRIER DISCHARGE LINE
RECEIVER
[HIGH PRESSURE VAPOR HIGH PRESSURE LIQUID NLow PRESSURE LIQUID RYLOW PRESSURE VAPOR
SV1095
FIGURE 43. HARVEST CYCLE — ICE ON BOTH EVAPORATORS
REAR
EXCHANGE EVAPORATOR EVAPORATOR
п NS COIE NS ENE !
1 Y
iG |
EXPANSION EXPANSION | т
VALVE VALVE IEE |
HOT GAS
SOLENOID VALVES
SUCTION LINE
EVAPORATOR
y
COMPRESSOR нии)
AIR /WATER COOLED
CONDENSER
DRIER DISCHARGE LINE
RECEIVER
EJHIGH PRESSURE VAPOR HIGH PRESSURE LIQUID NLow PRESSURE LIQUID КОМ PRESSURE VAPOR
SV1097
FIGURE 44. HARVEST CYCLE — ICE OFF FRONT EVAPORATOR BEFORE REAR EVAPORATOR
38
HARVEST CYCLE
(Self-Contained or Water Cooled)
HEAT FRONT
EXCHANGE EVAPORATOR
SUCTION LINE
EVAPORATOR
COMPRESSOR
DISCHARGE LINE
RECEIVER
EXPANSION
VALVE
HOT GAS
VAL
EXPANSION
VALVE
REAR
AIR/WATER COOLED
CONDENSER
FFJHIGH PRESSURE VAPOR MQHIGH PRESSURE LIQUID RYLOW PRESSURE LIQUID {SLOW PRESSURE VAPOR
EVAPORATOR
SV1096
FIGURE 45. HARVEST CYCLE — ICE OFF REAR EVAPORATOR BEFORE FRONT EVAPORATOR
Harvest Cycle Refrigeration Sequence
The harvest cycle begins with hot gas flowing through
both energized hot gas valves to heat the evaporators
(Figure 43). The hot gas valves are sized to allow the
proper amount of hot gas into the evaporators. This
specific sizing assures proper heat transfer without the
hot gas condensing to liquid and slugging the
compressor.
The ice may drop from the front evaporator or the rear
evaporator in any order. Figure 44 shows ice off the front
evaporator before the rear. After the ice falls off the front
evaporator, the front hot gas valve de-energizes. Figure
45 shows ice off the rear evaporator before the front.
After the ice falls off the rear evaporator, the rear hot
gas valve de-energizes.
HARVEST CYCLE PRESSURES
Ambient Head Suction
Temp. Pressure Pressure
°F PSIG PSIG
Air Cooled
50 125-150 65-75
70 125-150 66-76
80 140-165 72-82
90 150-175 80-90
100 175-200 100-110
Water Cooled
50 130-160 72-76
70 135-165 74-78
80 135-165 76-80
90 140-170 78-82
100 145-175 78-82
NOTE
The refrigeration system does not operate during the
automatic shutoff (a full bin of ice).
39
REFRIGERATION
SEQUENCE OF OPERATION
REMOTE ICE MACHINES
PRECHILL AND FREEZE CYCLE
HEAT FRONT REAR
EXCHANGE EVAPORATOR EVAPORATOR
LESS O NX OE NN SRNR |
i I
| I
I I
1 |
EXPANSION EXPANSION !
| VALVE VALVE i
ATFTTFETFIFIEETFEFETETRTITEY || ЕАО ААА 4
HOT GAS
SUCTION LINE SOLENOID VALVES
EVAPORATOR > >
COMPRESSOR = TL
DISCHARGE LINE VALUE
RN COR nT
PUMP \ HARVEST H.P.R. | | REMOTE
DOWN N PRESSURE SOLENOID > : CONDENSER
SOLENOID N REGULATING VALVE domo
N VALVE | КУ TINE
DRIER |
RECEIVER HEAD |
RUE PRESSURE ! |:
VALVE CONTROL ,
a es er ee ee se
[[JHIGH PRESSURE VAPOR [HIGH PRESSURE LIQUID [SLOW PRESSURE LIQUID RYLOW PRESSURE VAPOR SV1008
FIGURE 46. PRECHILL AND FREEZE CYCLE SEQUENCE
Prechill Refrigeration Sequence
There is no water flow over the evaporator during the
prechill. The refrigerant absorbs heat (picked up during
the harvest cycle) from the evaporators. The suction
pressure decreases during prechill.
Freeze Cycle Refrigeration Sequence
The refrigerant is absorbing heat from water running
over the evaporator surface. The suction pressure
gradually drops as ice forms.
40
REMOTE FREEZE CYCLE PRESSURES
Ambient Head Suction
Temp. Pressure Pressure
°F PSIG PSIG
-20 to 50 170-200 36-22
70 175-200 | 36-22
90 225-275 40-24
100 250-300 41-24
110 280-330 44-26
HARVEST CYCLE
(Remote Machines)
HEAT FRONT REAR
EXCHANGE EVAPORATOR EVAPORATOR
EFT | =
| т
| ! |
1 A Ё à |
IK I 8 y |
| |
| EXPANSION EXPANSION | ==> \!
> VALVE VALVE К |
LS шло АА ие НЕ ИТТ, PAGES EE mo 4
HOT GAS
SUCTION LINE SOLENOID VALVES
EVAPORATOR
COMPRESSOR Fr TAE ae Ил,
DISCHARGE LINE || CHECK
N HAAN = DAA he
PUMP N HARVEST H.P.R. REMOTE
DOWN N PRESSURE SOLENOID =o... CONDENSER
SOLENOID N REGULATING VALVE 22
N
DRIER IN ee
R RECEIVER HEAD
SERVICE PRESSURE
VALVE CONTROL
EJHIGH PRESSURE VAPOR HIGH PRESSURE LIQUID [SLOW PRESSURE LIQUID KSLOW PRESSURE VAPOR SV1099
FIGURE 47. HARVEST CYCLE — ICE ON BOTH EVAPORATORS
Y
HEAT FRONT REAR
EXCHANGE EVAPORATOR EVAPORATOR
= E ee EE ISIN ST EIN
1
1
К
EXPANSION EXPANSION | DON
VALVE VALVE gs
= AO EE EE == |
HOT GAS
SUCTION LINE SOLENOID VALVES— Ji
EVAPORATOR > 3
| COMPRESSOR I “E rea aia ea Trae Tae ETT
DISCHARGE LINE || MEC
N | er =
PUMP N A HARVEST H.P.R. REMOTE
DOWN N =) PRESSURE SOLENOID és CONDENSER
SOLENOID — REGULATING VALVE o
\ 8
DRIER = неее)
RECEIV RECEIVER HEAD
SERVICE PRESSURE
VALVE CONTROL
EJHIGH PRESSURE VAPOR [HIGH PRESSURE LIQUID RYLOW PRESSURE LIQUID KJLOW PRESSURE VAPOR SV1100
FIGURE 48. HARVEST CYCLE — ICE OFF FRONT EVAPORATOR BEFORE REAR EVAPORATOR
41
HARVEST CYCLE
(Remote Machines)
N
«5
\
HEAT FRONT N REAR
EXCHANGE EVAPORATOR \ EVAPORATOR
LESS aux cm ==
¡Ness |
1 ASSEN i
ss > |
сес I
CE EXPANSION 5 EXPANSION
Pe VALVE VALVE |
NT POSTS CTN eE, — }
HOT GAS
SUCTION LINE SOLENOID VALVES
EVAPORATOR
1 COMPRESSOR . PE aa
DISCHARGE LINE VALVE
EN pa e
PUMP N {HARVEST H.P.R. REMOTE
DOWN N © PRESSURE SOLENOID CONDENSER
SOLENOID Na м МЕСТО VALVE
``
DRIER LE —]———]]]]—]]—
RECEIVER HEAD
pa PRESSURE
VALVE CONTROL
HIGH PRESSURE VAPOR [HIGH PRESSURE LIQUID [SLOW PRESSURE LIQUID KNLOW PRESSURE VAPOR
ES
SV1101
FIGURE 49. HARVEST CYCLE — ICE OFF REAR EVAPORATOR BEFORE FRONT EVAPORATOR
Harvest Cycle Refrigeration Sequence
The harvest cycle begins with hot gas flowing through
both energized hot gas valves to heat the evaporators
(Figure 47). The hot gas valves are sized to allow the
proper amount of hot gas into the evaporators. This
specific hot gas valve sizing along with the harvest
pressure regulating (HPR) system assures proper heat
transfer without the hot gas condensing to liquid and
slugging the compressor. The harvest pressure
regulating (HPR) valve maintains suction pressure of
76-84 psig during the harvest cycle.
The ice may drop from the front evaporator or the rear
evaporator in any order. Figure 48 shows ice off the front
42
evaporator before the rear. After the ice falls off the front
evaporator, the front hot gas valve de-energizes. Figure
49 shows ice off the rear evaporator before the front.
After the ice falls off the rear evaporator, the rear hot
gas valve de-energizes.
REMOTE HARVEST CYCLE PRESSURES
Ambient Head Suction
Temp. Pressure Pressure
°F PSIG PSIG
-20 to 50 110-140 76-84
70 110-140 76-84
90 120-150 76-84
100 130-170 76-84
110 140-180 76-84
AUTOMATIC SHUT-OFF migration during the off cycle, preventing refrigerant
(Remote Machines) slogging upon start-up.
The liquid line solenoid (pump down solenoid) is
de-energized and the compressor continues to run. The IMPORTANT
compressor pumps refrigerant out of the low side of the Do not shut down a remote machine at the circuit
ice machine and into the high side past the check valve. breaker panel. The machine will not pump down
The low pressure cut-out control opens when the low before de-energizing the compressor for off cycle
side pressure reaches 12-17 psig. When the cut-out protection. Compressor failure may result when the
control opens the compressor is de-energized. With the ice machine is restarted.
compressor not operating it is protected from refrigerant
HEAT FRONT
EXCHANGE EVAPORATOR
EXPANSION
VALVE
EXPANSION
VALVE
HOT GAS
VAL
SUCTION LINE
EVAPORATOR
COMPRESSOR CHECK
DISCHARGE LINE VALVE
HARVEST H.PR
PRESSURE ENO
RECULATINO SOLENOID
VALVE
REMOTE
CONDENSER
PUMP
DOWN
SOLENOID
DRIER
RECEIVER
SERVICE
VALVE
RECEIVER HEAD
PRESSURE
CONTROL
ESLIQUID/VAPOR EQUALIZED TO AMBIENT CONDITIONS NJLOW PRESSURE VAPOR (12-17 PSIG)
REAR
EVAPORATOR
SV1102
FIGURE 50. AUTOMATIC SHUT-OFF REFRIGERATION SEQUENCE
43
SERVICE DIAGNOSTIC CHART
Symptom
Possible Cause
Corrective Action
Ice machine will not run.
ICE/OFF/ WATER PUMP switch.
a. Not in ICE position.
b. Defective/miswired.
High pressure cut-out control tripped.
a. Condenser water pressure
low or off (water cooled).
b. Condenser water temperature
above 90°F (water cooled).
c. Dirty condenser (air cooled).
d. Refrigerant overcharge.
e. High side refrigerant lines
or component plugged.
f. Headmaster control valve
defective.
g. H.P.C.O. control defective.
h. 7-second delay timer defective.
Circuit breaker tripped or blown fuse.
Bin switch.
a. Out of adjustment.
b. Defective.
Voltage too low.
5 amp fuse blown.
Set switch at ICE.
Check ICE/OFF/ WATER PUMP
switch, page 48.
Open water service valve at water
condenser inlet.
Maintain water supply temperature
between 33°F minimum and 90°F
maximum.
Clean condenser.
Evacuate/recharge, page 78.
Repair line/change drier.
Check control valve, page 72.
Check control, page 47.
Check timer, page 51.
Reset circuit breaker or replace fuse.
Check adjustment, page 46.
Check bin switch, page 46.
Electrical service must not fluctuate
more than + 10%.
Replace fuse.
Remote Machin nly:
Liquid line solenoid valve.
a. Defective coil.
b. Not opening.
Refrigeration problem.
Low pressure control.
Replace coil, page 75.
Replace valve, page 75.
Refer to Six-Step Diagnostic
Procedure, page 60.
Check control, page 52.
Dump valve will not energize at
beginning of freeze cycle.
Dump valve timer.
a. Out of adjustment.
b. Defective timer.
Adjust timer to 20 seconds.
Dump valve remains energized after
20-second prechill.
Dump valve timer.
a. Out of adjustment.
b. Defective timer.
Check timer, page 50.
Adjust timer to 20 seconds.
Check timer, page 50.
Compressor cycles intermittently or
will not run.
Voltage too low.
Defective start relay.
Defective start capacitor.
Wiring to compressor.
Defective compressor.
Electrical service must not fluctuate
more than + 10% of nameplate
voltage.
Check relay, page 56.
Check capacitor, page 57.
Check for loose connection/miswir-
ing or open and repiace.
Check compressor, page 56.
Remote Machines Only:
Low pressure cutout control.
Refrigeration problem.
Check control, page 52.
Refer to Six-Step Diagnostic
Procedure, page 60.
44
Symptom
Possible Cause
Corrective Action
Fan motor will not start (self-
contained air cooled machines).
Defective fan cycling control.
Defective fan motor.
Check fan cycling control, page 46.
Check fan motor.
Ice machine will not cycle into
harvest.
Refer to page 54 for Diagnostic
Procedures.
Ice machine repeatedly cycles into
harvest with little or no ice formation.
Refer to page 55 for Diagnostic
Procedures.
Ice machine does not cycle from
harvest to freeze when ice falls into
bin.
Bin switch out of adjustment.
Defective bin switch.
Defective 7-second delay timer.
Adjust bin switch, page 46.
Check bin switch, page 46.
Check timer, page 51.
Water runs over evaporator during
prechill cycle.
Drain line too small.
Water dump valve defective or dirty.
Drain line must be 3/4" 1.D.
Refer to Checking and Cleaning
Water Dump Valve, page 18.
Ice cubes too large/small.
Ice thickness probe out of
adjustment.
Adjust ice thickness probe, page 48.
Shallow or incomplete cubes;
incomplete ice fill pattern on
evaporator.
Ice thickness probe out of
adjustment.
Ice machine dirty.
Water filtration.
Ice making water inlet supply too
warm.
Incorrect incoming water pressure.
Leaking water dump valve.
Refrigeration problem.
Adjust ice thickness probe, page 48.
Clean and sanitize ice machine,
refer to pages 13 and 17.
Replace filters.
Maintain water supply temperature
between 33°F minimum and 90°F
maximum.
Water pressure must be 20-80 psi.
Refer to Checking and Cleaning
Water Dump Valve, page 18.
Refer to Six-Step Diagnostic
Procedure, page 60.
Ice machine does not release ice or
is slow to harvest.
Ice machine dirty.
Air-cooled models — low ambient.
Water regulating valve leaking
during harvest cycle (water-cooled
models).
R.T.V. sealant between white plastic
and metal evaporator missing.
Refrigeration problem.
Clean and sanitize ice machine.
Refer to pages 13 and 17.
Minimum ambient is 35°F.
Clean water regulating valve and
condenser.
Seal with food-grade silicone
(RTV) adhesive.
Refer to Six-Step Diagnostic
Procedure, page 60.
Low ice capacity.
Refer to Six-Step Diagnostic
Procedure, page 60.
45
COMPONENT FUNCTION, SPECIFICATIONS
AND CHECK PROCEDURES
BIN SWITCHES
Function
1. The front evaporator or rear evaporator bin switch
is controlled by movement of the corresponding
water curtain (see Water Curtain, page 49).
2. The front bin switch movement energizes relay A
and the rear bin switch movement energizes relay
B during the harvest cycle.
3. Either bin switch may be held open to shut the ice
machine off when the bin is full of ice
Specifications
Single pole, double throw, normally closed.
Bin Switch Setting (Figure 51)
1. During freeze cycle, pull water curtain away from
evaporator until ice machine shuts off.
NOTE
On remote models the ice machine may run 20 to 30
seconds before shutting off.
2. Slowly return curtain to evaporator. Ice machine
should restart as bottom edge of water curtain pas-
ses just inside edge of water trough.
The bin switch is factory set and should not require
adjustment. If bin switch adjustment is necessary, adjust
as follows:
1. Set ICE/OFF/WATER PUMP switch at OFF.
2. Slowly pull bottom of water curtain away from
evaporator, then slowly return curtain toward
evaporator.
3. Loosen appropriate locking screw.
4. If bin switch clicks before water curtain reaches
water trough, move lever toward water curtain.
5. If bin switch clicks too far into water trough, move
lever away from water curtain.
6. Tighten locking screw.
7. Set ICE/OFF/ WATER PUMP switch at ICE after
adjustment is complete.
Bin Switch Replacement
If the bin switch does not operate properly after adjust-
ment, check bin switch with Ohmmeter and/or voltmeter
46
while depressing and releasing bin switch. If bin switch
does not open and close properly, replace switch.
LOCKING
SCREWS
—= —
LEVERS
WATER
CURTAIN
G12SV051
FIGURE 51. BIN SWITCH CHECK
FAN CYCLE CONTROL ;
(Self-Contained Air-Cooled Models)
Function
Cycles fan motor on and off to maintain proper operating
discharge pressure.
The fan cycle control is normally closed and opens on
a drop in discharge pressure.
Specifications
Cut-out — (opens) 175 psig.
Cut-in — (closes) 225 psig.
Check Procedures
1. Verify fan motor windings are not open or grounded
and fan spins freely.
2. Connect manifold gauges to ice machine. Refer to
page 73.
3. Hook voltmeter in parallel (across) to the fan cycle
control, leaving wires attached.
4. Pressure above 225 psig — read 0 volts and fan
should be running.
Pressure below 175 psig — read line voltage and
fan should be off.
Replace Fan Cycle Control if:
Control does not operate within psig range listed above.
FLOAT VALVE
Function
Maintains correct water level in water trough.
Water Level Setting Check (Figure 52)
1. Set ICE/OFF/WATER PUMP switch at OFF.
CAP AND
FILTER SCREEN ON/OFF
—_—\ N FLOAT
EA A VALVE
|
o >
WATER
| TROUGH
a
FLOAT
CORRECT
WATER LEVEL
DRAIN PLUG
G125V052
FIGURE 52. WATER LEVEL SETTING CHECK
2. Remove drain plug from trough and allow water to
drain.
3. Reinstall drain plug on trough and allow trough to
refill to proper level of offset in trough.
The float valve is factory set for proper water level. If
adjustment is necessary, carefully bend float arm to
achieve correct level.
Fioat Valve Replacement
If float valve cannot be adjusted to maintain proper
water level in trough, replace float valve. The float valve
may be dirty. Attempt to clean the valve before replace-
ment.
HIGH PRESSURE CUT-OUT
CONTROL — H.P.C.O.
Function
Safety control which turns the ice machine off if sub-
jected to excessive high-side pressure. The H.P.C.O.
control is a normally closed control and opens on a rise
in pressure. See Figure 6, page 8.
Specifications
Cut-out — 440 psig + 10.
Cut-in — manual reset (below 300 psig to reset).
Check Procedure
1. Set ICE/OFF/ WATER PUMP switch at OFF and
reset H.P.C.O. (if tripped).
2. Hook voltmeter in parallel (across) to the H.P.C.O.
leaving wires attached.
3. Connect manifold gauges. Refer to page 73.
4. Procedures:
a. Water-Cooled Machines — Close the water
service valve to the water condenser inlet. See
Typical Installation illustration, page 5.
b. Air-Cooled Machines — Disconnect fan motor.
5. Set ICE/OFF/ WATER PUMP switch to ICE.
No water or air flowing through the condenser will
cause the H.P.C.O. control to turn the ice machine
off because of excessive high pressure. Watch the
high-pressure gauge and record the pressure at
which the cut-out takes place.
Replace the H.P.C.O. control if:
1. The control will not reset. (Note: High-side pressure
must be below 300 psig before resetting.)
2. The control does not open at the specified cut-out
point of 440 psig + 10.
47
ICE THICKNESS PROBE
Function
Maintain correct ice thickness.
Ice Thickness Check (Figure 53)
Be sure the water curtain is in place to prevent water
from splashing out of water trough.
Inspect bridge connecting the cubes. The bridge should
be approximately 1/8" thick.
The ice thickness probe is factory set to maintain 1/8
inch ice bridge thickness. If adjustment is necessary,
adjust as follows:
1. Turn adjustment screw on ice thickness probe
clockwise to increase thickness, counter-clockwise
to decrease thickness.
ADJUSTING
`
\
\
1/8" BRIDGE
VA THICKNESS Xx
G6SV042
ICE/OFF/WATER PUMP TOGGLE
SWITCH
Function
Place ice machine in ICE, OFF, or WATER PUMP mode
of operation.
Specifications
Double pole/doubie throw.
Check Procedure
1. Check for proper line voltage to the ice machine
(£ 10%).
2. Inspect switch (Figure 54) for correct wiring.
3. Inspect terminals for clean, tight connections.
4. Check across switch terminals with voltmeter for
correct readings as follows (replace switch if read-
ings are incorrect):
a. Switch set at ICE:
FIGURE 53. ICE THICKNESS CHECK
NOTE
Do not turn the adjusting screw more than 1/4 turn
at a time. If necessary, check the bridge for two
harvest cycles after initial adjustment before adjust-
ing again.
2. Ensure ice thickness probe wires and bracket do
not restrict movement of probe.
48
Switch Position Voltage
48 to 50 Open Line Voltage
48 to 49 Closed 0 Volts
44 to 45 Closed 0 Volts
b. Switch set at OFF:
Switch Position Voltage
48 to 50 Open Line Voltage
48 to 49 Open Line Voltage
44 to 45 Open Line Voltage
c. Switch set at WATER PUMP:
Switch Postion Voltage
48 to 50 Closed O Volts
48 to 49 Open Line Voltage
44 to 45 Open Line Voltage
TOGGLE SWITCH WIRING
451! "149
(
44|1 *+ 1148
1150
SELF CONTAINED REMOTE
SV1108
FIGURE 54. ICE/OFFWATER PUMP
SWITCH CHECK
WATER CURTAIN
Function
1. Prevents water from splashing into bin.
2. Acts as a lever to depress and release bin switches
as ice falls from the evaporator.
Check Procedure
1. Pull bottom of water curtain (Figure 55) away from
evaporator, then release. Curtain should fall back
to evaporator.
BIN SWITCH
CURTAIN
HANGER
(Lift tabs with
thumbs while
lifting hanger)
PS
> po
LOOSEN HANGER SCREWS \ LL
AND ADJUST HANGERS TO К
ELIMINATE SIDE TO SIDE (2
MOVEMENT \ |
WATER A )
CURTAIN |
7
{
CURTAIN PIN
G125V055
NOTE
Water curtain heads must be positioned under cur-
tain hanger tabs. Curtain must be centered on
evaporator when installed.
WATER PUMP
Function
1. Pump water over evaporator during freeze cycle.
2. Pump water through the dump valve and down the
drain during first 20 seconds of freeze cycle.
Specifications
Refer to ice machine serial number plate for correct
voltage and running amps.
Check Procedure
NOTE
Water pump runs quietly with no water in water
trough.
FIGURE 55. WATER CURTAIN CHECK
2. Move curtain from side to side. There should be little
or no movement.
The water curtain is factory set and should require
no adjustment. If adjustmentis necessary, adjust as
follows:
a. Remove water curtain.
b. Loosen curtain hanger screws (two per hanger)
and slide hangers in or out to prevent side to
side movement.
c. Retighten hanger screws.
d. Reinstall water curtain.
Set ICE/OFF/ WATER PUMP switch at WATER PUMP.
If water pump runs with switch at WATER PUMP and
does not run with switch set at ICE, the water pump is
operating properly.
If water pump will not run with switch set at WATER
PUMP, check the following procedures:
1. Check for proper line voltage to the ice machine
(£ 10%).
2. Unplug the water pump.
3. Set ICE/OFF/WATER PUMP switch at WATER
PUMP and check voltage at water pump electric
plug receptacle.
a. Line voltage — replace water pump after verify-
ing pump impeller is not blocked by foreign
objects.
NOTE
For proper ice machine operations replace only with
Manitowoc original (OEM) water pump designed and
sized specifically for this ice machine.
b. No voltage — Check toggle switch (page 48)
and check fuse on relay board.
49
DUMP VALVE TIMER
Function
The S.C.R. switch is normally closed (N.C.) and ener-
gizes the dump valve for the first 20 seconds of the
freeze mode. This prechills the evaporator while flush-
ing the water from the last freeze mode. The timer is
factory set at 20 seconds and should require no further
adjustment.
Specifications
208-230 volt, 50/60 Hertz.
Normally closed silicon rectifier (S.C.R.) switch.
Check Procedure
Clip voltmeter leads across S.C.R. switch terminals #1
and #2. Keep all wire leads attached.
Li L2
OUMP VALVE TIMER
[2 — 3)
- МИ
DUMP VALVE
NY 181 | С°) 5осЕМОЮ
№ L N.C. SCR SWITCH NY
WATER PUMP \
SV1093
FIGURE 56. DUMP VALVE TIMER CHECK
NORMAL OPERATIONAL SEQUENCE
(No Failure)
Voltage Reading
No Failure Terminals #1 and #2
First 20 seconds of
freeze cycle. Dump 0-4 Volts
valve energized.
After 20 seconds into
freeze cycle. Dump Line Voltage
valve de-energized.
DUMP VALVE TIMER FAILURE CHART
Voltage
be chattering.
Symptom Terminals #1 and #2 Cause
Dump valve will not energize. Line voltage. S.C.R. switch is failed open and will
not close.
Dump valve energized and will not | 0-4 volts. S.C.R. switch is failed closed and
de-energize after 20 seconds. will not open.
Dump valve de-energized and may | Approximately 1/2 line voltage. S.C.R. switch is failed half-wave.
50
7-SECOND DELAY TIMER
Function |
The normally closed S.C.R. switch is in series with the
primary of the transformer. The timer resets the ice
machine to the freeze mode by momentarily interrupting
the power to the transformer. The time delay is initiated
after relays A and B are both energized through the front
and rear bin switches. On completion of delay period (7
seconds) the S.C.R. switch opens and the transformer
power supply is interrupted. This cycles the ice machine
back into the freeze mode.
Specifications
208-230 volt, 50/60 Hertz.
Normally closed silicon rectifier (S.C.R.) switch.
Check Procedure
Clip voltmeter leads across S.C.R. switch terminals #1
and #2. Keep all wire leads attached. The transformer
and Harvest Pressure Limiter Control (remote models)
must operate properly to check 7-second delay timer.
L1 L2
7-SECOND DELAY TIMER
| HH 3 21
| al | Г
N NO
) $
La 148 1
TRANSFORMER /
TY
S.CR. SWITCH N.C
MT
SV1109
FIGURE 57. 7-SECOND COMPRESSOR
DELAY TIMER
NORMAL OPERATIONAL SEQUENCE
(No Failure)
Toggle Switch in ICE Position:
Voltage between terminals #1 and #2 must be 0-4 volts.
The ice machine will freeze ice and cycle into Harvest mode.
Approximately 7 seconds after relays A and B are both energized
during harvest the voltage will “jump” to line voltage, then back to
0-4 volts.
7-SECOND DELAY TIMER FAILURE CHART
Symptom Voltage Cause
Terminals #1 and #2
Ice machine will freeze ice but Line voltage. S.C.R. switch is failed open and
will not go into harvest cycle. will not close.
Ice machine will not cycle from 0-4 volts continually after both S.C.R. switch is failed closed
harvest mode on the 7-second relays A and B are energized and will not open.
delay timer. It will cycle back into | during harvest.
freeze mode on 4-1/2 to 5 minute
safety timer or harvest pressure
limiter (remotes).
The hot gas valves chatter Approximately 1/2 line voltage. S.C.R. switch is failed half-wave.
during the harvest cycle.
51
LOW PRESSURE CUT-OUT CONTROL
(Remote Machines Only)
Function
1.
Energizes and de-energizes the contactor to start
and stop the ice machine.
2. A drop in suction pressure opens the low pressure
cut-out control.
Specifications
Cut-out — 15 psig + 3.
Cut-in — 40 psig + 3.
Check Procedure
1.
2.
52
Connect manifold gauges, page 73.
Connect a voltmeter in parallel (across) wires leav-
ing the cut-out control.
Set toggle switch to OFF position. The liquid line
solenoid valve will de-energize and the suction
pressure will begin to decrease. The low pressure
cut-out control will open at 15 psig (+ 3). The con-
tactor will de-energize and the voltage across the
L.P. cut-out control will be “line voltage.”
Set toggle switch to ICE position. The liquid line
solenoid valve will energize and the suction pres-
sure will rise. The low pressure cut-out control will
close at 40 psig. The contactor will energize and the
voltage reading across the low pressure cut-out will
be “0.”
Replace the low pressure cut-out control if it does
not open and close properly or does not maintain
proper settings.
HARVEST PRESSURE LIMITER
CONTROL
(Remote Machines Only)
Function
1.
Safety control which cycles the ice machine out of
a harvest cycle and returns it to a freeze cycle if
suction pressure becomes excessive.
2. The H.P.L. safety control is normally closed and
opens on a rise in suction pressure.
Specifications
Cut-out — 110 psig + 5.
Cut-in — 85 psig + 7.
Check Procedure
1.
Connect a voltmeter in parallel (across) the H.P.L.
safety control.
Connect manifold gauges, page 73.
Pressures:
a. When suction pressure rises above 110 psig
the H.P.L. safety control must open. The
voltmeter must read “line voltage.”
b. When the suction pressure drops below 85 psig
the H.P.L. safety control must close. The
voltmeter must read “0" volts.
Replace the H.P.L. safety control if it does not open
or close properly or does not maintain proper set-
tings.
ELECTRONIC CONTROL CIRCUITRY
The ice machine uses either a transformer board with a
plug-in sensor module or a unitized sensor board to
control the ice thickness and initiate the harvest cycle.
See Figure 58.
The transformer board and sensor module are not avail-
able as replacement parts. If either fails, replace both
with a unitized sensor board.
Refer to ice machine Electrical Sequence of Operation
(see Table of Contents) for operation of control circuitry.
SENSOR MODULE
The plug-in sensor module has four functions:
1. A relay to energize or de-energize electrical com-
ponents utilized during the harvest cycle.
2. Electronics to sense when water is in contact with
the ice thickness control probe.
3. A6-to 10-second timer ensuring the water flowing
over the evaporator completes an electrical circuit
through the ice thickness control probe.
4. A safety timer ensuring the ice machine does not
remain in the harvest cycle for longer than 4 to 5
minutes.
TRANSFORMER BOARD
The transformer board reduces line voltage to the sen-
sor module to 12-24 VAC.
UNITIZED SENSOR BOARD
This board combines the functions of the sensor module
and transformer board into one assembly. >
ICE THICKNESS CONTROL PROBE
The ice thickness control probe adjusts the ice thick-
ness. Water comes into contact with the two probes for
6 to 10 seconds and completes an electrical circuit
initiating the harvest cycle.
TRANSFORMER
BOARD
WITH PLUG-IN
MODULE
|
|
Bll MANITOWOC
D ICE SENSOR ==
“f —
199) = oT
20) 7 | MANITOWOC
2, of ICE SENSOR
Uy | -
UNITIZED SENSOR
BOARD BLUE OR ORANGE
(INTERCHANGEABLE)
G6SVO48
FIGURE 58. ELECTRONIC CONTROLS
53
DIAGNOSING ELECTRONIC CONTROL CIRCUITRY
IMPORTANT
The transformer board and sensor module are not
available as replacement parts. If either fails, replace
both with Unitized Sensor Board.
 CAUTION
THESE PROCEDURES MUST BE PERFORMED
BY A QUALIFIED TECHNICIAN.
Do not make adjustments or turn the ice machine off
until the malfunction is identified. The problem may be
intermittent and you may lose the opportunity to make
the checks while it is malfunctioning.
Follow the systematic approach throughout the diag-
nosis and write down information as it is collected. This
will keep you organized.
A. POSSIBLE PROBLEM:
ICE MACHINE WILL NOT GO INTO
HARVEST
NOTE
These procedures require the use of a jumper wire
with clip ends attached. |
Does the ice machine go into the harvest cycle?
IF NO: The ice machine still will not harvest.
Proceed to Step 3.
IF YES: The entire control circuitry is function-
ing properly. Check the following:
a. lce bridge thickness probe adjustment,
page 48.
b. Ice bridge thickness probe has scale
build-up acting as an insulator. Clean
probe.
c. The water to the ice machine may not offer
a low enough resistance across the probes
for proper operation. To check, put a small
amount of salt into water trough to lower the
resistance level of the water. If the ice
machine goes into harvest after putting salt
into the water trough, order Resistor Kit,
part number 76-2266-3, from your local
Manitowoc Distributor. Install resistor kit
across terminals 20 and 21. The ice
machine will now operate properly.
Step 1: Check primary voltage at transformer terminals
1 and 2 on board.
Does voltmeter indicate line voltage (+ 10%)?
IF NO: Check for correct wiring and loose or
corroded connections. Also check 7-second
delay timer (page 51) and Harvest Pressure
Limiter Control (page 52).
Do not proceed until line voltage is restored.
IF YES: Proceed to Step 2.
Step 2: Clip the leads of the jumper wire to the ice
thickness control probe, Figure 59.
54
G6SV049
FIGURE 59. JUMPER WIRE CONNECTED
TO PROBES
У
В
MANITOWOC
ICE SENSOR
7
т
NOTE: BOARD MUST BE IN ICE MACHINE
WITH ALL WIRES ATTACHED. G6SV051
FIGURE 60. UNITIZED SENSOR BOARD
Step 3: Disconnect wires from terminals 20 and 21 on
board. Connect jumper wire to terminals 20 and
21, Figure 60.
Does the ice machine go into the harvest cycle?
IF NO: Install new unitized sensor board.
If ice machine you are working on is transformer
board/sensor module system, replace both
components with unitized sensor board.
IMPORTANT
Failure to check primary voltage (Step 1) can result
in a misdiagnosis.
B. POSSIBLE PROBLEM:
ICE MACHINE PREMATURELY
GOES INTO HARVEST WITHOUT
ICE FORMATION
Step 1: Check primary voltage at transformer terminals
1 and 2 on board.
Does voltmeter indicate line voltage (+ 10%)?
IF NO: Check for correct wiring and loose or
corroded connections. Also check 7-second
delay timer (page 51) and Harvest Pressure
Limiter Control (page 52).
Do not proceed until line voltage is restored.
IF YES: Proceed to Step 2.
Step 2: Disconnect wires on terminals 20 and 21 on
unitized sensor board. Activate bin switches to
cycle ice machine into the freeze cycle.
Does the ice machine stay in the freeze cycle?
IF NO: Ensure there is no moisture between
terminals 20 and 21 on board. If no moisture,
install new unitized sensor board.
If ice machine you are working on has trans-
former board/sensor module controls, replace
both components with unitized sensor board.
IF YES: The ice thickness probe is causing the
malfunction. All other components are operat-
ing properly. The ice thickness probe may be
dirty. Clean the probe before replacing.
IMPORTANT
Failure to check primary voltage (Step 1) can result
in a misdiagnosis.
IF YES: The ice thickness probe is causing the
malfunction. All other components are function-
ing properly. The ice bridge thickness probe
may only be dirty. Clean the probe before
replacing.
55
DIAGNOSING SINGLE (1) PHASE COMPRESSOR
AND START COMPONENTS ELECTRICALLY
USE COPPER CONDUCTORS ONLY TO CRAMK-CASE
HEATER
Dota uy
|
I
| 2 USE 5 AMP MT
CONTACTOR (ON RELAY BOARD)
47
— TO 44 1002.5
— SWTCH
+ 46
ul
,
ви
START
CAPACITOR
| 1) 55
i
Ln
MN
MOTOR CODE
TO 1 TRANSFER
BOARD
1*
3*
*Motor code determined by 6th digit in serial number.
*Compressor at room temperature.
COMPRESSOR
Bristol
M53A223BBC
OHM VALUES** LOCKED ROTOR AMPS
C-S C-R S-R
0.601 1.800 2.401 97.0 Amps .
0.570 2.030 2.600 97.0 Amps
810670A
FIGURE 61. ONE PHASE COMPRESSOR AND START COMPONENTS SCHEMATIC
Perform the following tests, in sequence, using a quality,
calibrated volt-ohmmeter.
1. Verify electric power to the ice machine at time of
compressor start-up is 208/230 V (+ 10%).
2. Verify the following control components are in the
closed position:
Bin Switch, page 46.
High Pressure Cut-Out Control, page 47.
ICE/OFF/ WATER PUMP Switch, page 48.
Contactor.
Low Pressure Cut-Out Control (Remote
Machines), page 52.
ÁA WARNING
DISCONNECT ELECTRIC POWER TO THE ICE
MACHINE AT THE ELECTRIC SERVICE SWITCH
BOX BEFORE PROCEEDING WITH THE FOL-
LOWING STEPS.
3. Continuity check of start relay (RX10,000 scale):
a. Disconnect wires from start relay. (If relay is
being removed, keep it upright.)
56
b. Terminals 1 and 2 (contact normally closed).
No continuity — replace relay.
Continuity — relay OK.
с. Terminals 2 and 5.
No continuity — replace relay.
Continuity — relay OK.
4. Continuity check of compressor:
NOTE
Compressor must be at room temperature.
a. Disconnect wires from compressor terminals.
b. Terminal C to Terminal R.
Continuity — see step e.
No continuity — open run winding. Replace
compressor.
C. Terminal C to Terminal S.
Continuity — see step e.
No continuity — open start winding.
Replace compressor.
d. Terminal C to shell of compressor.
Continuity — compressor grounded.
Replace compressor.
No continuity — compressor not grounded.
Au
e. Check winding resistance against values given
in chart. The resistance values from C-R and
C-S added together should equal the reading
from S to R.
5. Capacitor check (run and start):
a. Capacitors may show visual evidence of failure,
such as a bulged terminal end or a ruptured
membrane. However, do not assume a capa-
citor is good just because there are no visual
signs of failure.
An effective test is to disconnect leads to the
capacitor in the ice machine and connect them
to a good capacitor.
C.
Use of a capacitor analyzer is recommended
when checking a suspect capacitor. Follow in-
structions supplied with capacitor analyzer.
If all of the capacitor tests prove satisfactory
and the compressor still fails to start:
1) Replace start relay.
The new relay eliminates any faulty electri-
cal characteristics such as improper pick-
up or drop-out, which cannot be determined
by the tests.
2) If new relay fails to correct the problem, the
compressor can be considered inoperative
because of internal defects. Replace com-
pressor.
57
DIAGNOSING THREE (3) PHASE COMPRESSOR
AND START COMPONENTS ELECTRICALLY
L2 LS u
SN
TO CRANK=-
CASE HEATER
LP
USE 5 AMP MTH
(ON RELAY BOARD)
NV me oa
+ 53 ) 82 Y MM 47
< L zZ Fi
$ $ $ $
2 u 45
LI | SWITCH
CONTACTOR
ttt orem нь
10 | TNS RAR
BOARD
COMPRESSOR
10 |
COMPRESSOR
Bristol
M53A223DBL
OHM VALUES" LOCKED ROTOR AMPS
T1-T2 T1-T3 T2-T3
1.22 1.22 1.22 70.0 Amps
*Compressor at room temperature
8106708
1.
2.
FIGURE 62. THREE PHASE COMPRESSOR AND START COMPONENTS SCHEMATIC
Perform the following tests, in sequence, using a quality,
calibrated volt-ohmmeter.
Verify electric power to ther ice machine at time of
compressor start-up is 208/230 V (£10%)
Verify the following control components are in the
closed position:
58
Bin Switch, page 46.
High Pressure Cut-Out Control, page 47.
ICE/OFF/ WATER PUMP Switch, page 48.
Contactor.
Low Pressure Cut-Out Control (Remote
Machines), page 52.
Check amperage in each line. One or two high-
amperage legs on a three phase motor indicates an
unbalanced voltage supply, or a winding inbalance.
If all three legs are not drawing approximately equal
amperage, temporarily switch the leads to the motor
to determine if the high leg stays with the line or
stays with the terminal. If the high amperage stays
with the line, the problem is in the line voltage
supply. If the amperage reading stays with the
terminal the problem is in the compressor motor.
If the amperage is sufficiently unbalanced to
cause the overload to trip, and the voltage supply
is unbalanced, check with the power company to
see if the condition can be corrected. If the voltage
supply is balanced, indicating a defective motor
phase, the compressor should be replaced.
A WARNING
DISCONNECT ELECTRIC POWER TO THE ICE
MACHINE AT THE ELECTRIC SERVICE SWITCH
BOX BEFORE PROCEEDING WITH THE FOL-
LOWING STEPS.
4. Continuity check of compressor (ohm check):
NOTE
Compressor must be at room temperature.
Ni
Disconnect wires from compressor terminals.
Check continuity between terminals T1 to T2,
T1 to T3, and T2 to T3.
Continuity — see step d.
No continuity — open winding.
Replace compressor.
Check continuity at each terminal, T1, T2, and
ТЗ, to compressor shell.
Terminals to shell of compressor.
Continuity — compressor grounded.
Replace compressor.
No continuity — compressor not grounded.
Check winding resistance against values given
in Figure 62. The values of all readings should
be equal.
59
REFRIGERATION AND OTHER NON-ELECTRICAL
PROBLEMS
INTRODUCTION TO THE SIX-STEP
DIAGNOSTIC PROCEDURE
6. FINAL
ANALYSIS — . VISUAL
5. REFRIGERATION INSPECTION
CHECKS
2. ICE
4. WATER PRODUCTION
SYSTEM N_
3. ICE FILL
PATTERN
G6SV054
FIGURE 63. SIX-STEP DIAGNOSTIC PROCEDURE
The Six-Step Procedure (Figure 63) is designed to
increase the accuracy of your service call, while
decreasing the time required to identify any problems.
60
Refrigeration components will react and try to compen-
sate for nonrefrigeration component problems. By fol-
lowing this procedure step by step, problems that affect
the refrigeration sequence can be identified without
needless changing of components.
Each of the six steps have several items to check before
proceeding to the next step. Follow each step carefully
as the problem may be identified prior to the completion
of all six steps.
Step 6 requires the use of information gathered in the
previous steps. Write down information as you collect it
and record it on the Refrigeration Component Diagnos-
tic Chart, page 71. This will keep you organized and
simplify the 6th step of determining the malfunction.
NOTE
Do not make adjustments or turn the ice machine off
until you have identified the malfunction. The prob-
lem may not repeat itself.
STEP 1 — VISUAL INSPECTION
Talk to the ice machine user to identify the perceived
problem(s). The user's information could help you start
in the right direction and may be a determining factor in
your final diagnosis.
Following are a few questions to consider when talking
to the ice machine user:
When is the ice machine malfunctioning? (Night,
day, all the time, during freeze cycle, harvest cycle,
When do you notice low production? (One day a
week, every day, weekends, etc.)
Can you describe exactly what the ice machine
seems to be doing?
Has anyone been working on the ice machine?
Were items such as boxes obstructing air flow
moved from around the ice machine before you
arrived?
etc.)
EQUIPMENT VISUAL INSPECTION
(Record Your Findings on Refrigeration Component Diagnostic Chart, Page 71)
— Possible Problem Actual Finding Corrective Measure
1. lce machine not properly
installed.
2. Air temperatures/air flow
restrictions, etc.
3. Air space clearances at back
and sides of ice machine.
4. ice machine not level side-to-
side, back-to-front.
5. Air-cooled condenser dirty.
6. Ice machine not on separate
fused electrical circuit.
7. Drains not run separate
and/or vented.
8. Water filtration restricted (if
used).
9. Remote condenser line set
not properly installed.
Reinstall in accordance with
installation manual.
Reinstall in accordance with
installation manual.
Must have a minimum of 5 inches
clearance around all sides and top
of machine.
Level machine.
Clean condenser.
Install electrical in accordance with
installation manual.
Run drains separate and vent
according to installation manual.
Install new water filter.
Refer to Installation Instructions.
check.
NOTE
Steps 2, 3 and 4 can be completed in conjunction with each other. Be careful not to interfere with the ice production
61
STEP 2 — ICE PRODUCTION
The amount of ice a machine produces is in direct
relationship to water and air temperatures, this means
an ice machine produces more ice in a 70°F room with
50°F water than in a 90°F room with 70° F water.
ICE PRODUCTION CHARTS
(Lbs. of Ice per 24 Hours)
Water-Cooled
OPERATING CONDITIONS
1. Condenser inlet air temperature
2. Water inlet temperature (taken at float
outlet)
3. The published 24-hour ice production at the
above conditions: 16/24 hours
ICE PRODUCTION CHECK
1. Freeze time + harvest time
= total cycle time
2. 1440 + total cycle time
= cycles/day
3. Weight 1 harvest x cycles/day
= Ib/24 hours
Water Temp. °F
Air Temp. °F 50 70 90
70 1290 1150 1010
80 1280 1140 1000
90 1270 1130 990
100 1260 1120 980
Air-Cooled
Water Temp. °F
Air Temp. °F 50 70 90
70 1260 1170 1080
80 1200 1100 1000
90 1150 1040 930
100 1040 930 840
NOTE
To use the 24-hour ice production formulas, time
must be in minutes and weight of ice in pounds.
Remote Machines
Water Temp. °F
Air Temp. °F 50 70 90
-20 to 70 1200 1100 1000
90 1130 1030 930
100 1060 960 860
110 990 890 790
These figures are based on a clean, properly maintained
ice machine running continually for a 24-hour period,
with an average ice weight of 8.12 Ib. to 9.25 Ib. per
harvest.
Use the following to check and compare ice production:
IMPORTANT
Water curtain must be in place to assure no water is
being lost while checking ice production.
62
Times are in minutes.
Example: 1 min. 15 sec. convert to 1.25 min.
15 sec. + 60 sec. = .25 min.
Weights are in pounds.
Example: 9 Ib. 4 oz. convert to 9.25 Ib.
4 07. + 16 07. = .25 Ib.
Compare your findings in the Ice Production Check to
published specifications in Operating Conditions.
Record your findings on Refrigeration Diagnostic Chart,
page 71.
A. Ice Production OK:
Determine if another ice machine is needed, more
storage capacity, or if moving existing equipment to
lower load conditions will meet the customer's
needs. (Contact local Manitowoc Distributor for
options and accessories available.)
B. Low Ice Production:
Record your findings on the Refrigeration
Diagnostic Chart, page 71, Step 2 (actual findings
column of chart).
Continue through Six-Step Procedures.
STEP 3 — ICE FILL PATTERN
The fill patterns on the evaporators are normal when the
ice thickness is a uniform 1/8 inch from top to bottom
and side to side. (The ice bridge is the inter-connecting
waffle between the cubes. Refer to page 48.) The water
should freeze on the entire evaporator at the same time
and both evaporators at the same rate. Ice forming on
the bottom of an evaporator then working its way up to
the top is not normal and must be noted as “thin on top
and thick on bottom.”
IMPORTANT
The water curtain must be in place to ensure no
water is being lost while checking ice fill pattern.
Examples of ice fill patterns:
Normal ice fill — uniform 1/8-inch bridge thickness on
entire evaporator surface.
Thick on top and thin on bottom.
Thin on top and thick on bottom.
Spotty ice fill (i.e., corner not filling, etc.).
Record your findings for both front and rear fill patterns
on the Refrigeration Diagnostic Chart, page 71, Step 3
(actual findings column of chart).
STEP 4 — WATER SYSTEM
Water related problems in ice machines often have the
same symptoms as a refrigeration system malfunction.
Water area failures must be identified and eliminated
prior to changing of refrigeration components. An ex-
ample is a water dump valve leaking during the freeze
cycle and a starving TXV. The characteristics of both
failures are similar.
CHECK WATER RELATED PROBLEMS
(Record Your Findings on Refrigeration Component Diagnostic Chart, Page 71,
Step 4, Actual Findings Column of Chart)
Possible Problem
Actual Finding
Corrective Measure
—
. Water area (evaporator) dirty.
2. Water inlet pressure not
between 20-80 psi.
3. Incoming water supply temper-
ature must be 35°F to 90°F.
4. Water filter restricted (if used).
5. Dump valve malfunctioning.
6. Vent tube not installed on water
outlet drain.
7. Water trough hoses leaking water.
8. Water float valve stuck open or
out of adjustment.
9. Water freezing behind
evaporators.
10. Water freezing between white
plastic extrusions and evaporator.
11. Water flow uneven across
evaporator(s).
Clean.
Install water regulator valve or
increase water pressure.
Too hot— check hot water line
check valves in other store
equipment.
Replace filter.
Clean dump valve. Replace as
needed, page 18.
See Installation Instructions.
Install properly or replace.
Readjust float, page 47.
Check water flow.
Seal with food-grade silicone
(RTV) adhesive.
Clean ice machine. Check water
flow rate.
63
STEP 5 — REFRIGERATION
The refrigeration section requires taking several checks
to gather information.
CYCLE TIME CHART
NOTE
Only proceed to Refrigeration System Step 5 after
Steps 1-4 have been thoroughly checked and a final
diagnosis could not be determined.
NOTE
To calculate total cycle time, add harvest time to
freeze time listed in charts.
OPERATIONAL PRESSURE CHART
Freeze Cycle Harvest Cycle
Ambient Head Suction Head Suction
Temp. Pressure | Pressure | Pressure | Pressure
°F PSIG PSIG PSIG PSIG
Water-Cooled
50 225-235 38-24 130-160 72-76
70 225-235 38-24 135-165 74-78
80 225-235 38-24 135-165 76-80
90 225-235 40-24 140-170 78-82
100 225-235 44-24 145-175 78-82
Air-Cooled
50 175-225 38-24 125-150 65-75
70 175-225 40-26 125-150 65-75
80 200-250 42-27 140-165 72-82
90 220-270 44-28 150-175 80-90
100 275-325 46-30 175-200 100-110
Remote Machines
Freeze Cycle Harvest Cycle
Ambient Head Suction Head Suction
Temp. Pressure | Pressure | Pressure | Pressure
°F PSIG PSIG PSIG PSIG
-20 to 50 170-200 36-22 110-140 76-84
70 175-200 36-22 110-140 76-84
80 200-225 38-22 120-150 76-84
90 225-275 40-24 130-170 76-84
100 250-300 41:24 140-180 76-84
110 280-300 44-26 150-190 76-84
64
Ambient Freeze Time
Temp. Water Temp. Harvest
"Е 50°F 70°F 90°F Time
Water-Cooled
70 7.5-9.0 8.5-10.0 | 10.0-11.5
80 7.5-9.0 8.5-10.0 10.0-11.5 1.0-2.5
90 8.0-9.5 9.0-10.5 10.5-12.0
100 8.0-9.5 9.0-10.5 10.5-12.0
Air-Cooled
70 7.5-9.0 8.5-10.0 9.5-11.0
80 8.0-9.5 9.0-10.5 | 10.5-12.0 1.0-2.5
90 8.5-10.0 10.0-11.5 11.5-13.0
100 9.5-11.0 11.0-12.5 12.5-14.0
Remote Machines
Condenser Freeze Time
Ambient
Temp. Water Temp. Harvest
F 50°F 70°F 90°F Time
-20 to 70 8.0-9.5 9.0-10.5 10.5-12.0 ;
90 8.5-10.0 9.5-11.0 11.0-12.5 1.0-2.5
100 9.5-11.0 | 10.5-12.0 | 12.0-13.5
110 10.5-12.0 11.5-13.5 13.5-15.5
Record Pressure of
Freeze and Harvest Cycles
Freeze Cycle Discharge Suction
1. One minute to freeze
2. Middle of freeze
3. End of freeze
Harvest Cycle
1. Start of harvest
2. Middle of harvest
3. End of harvest
md
Step 5A — Analyze Discharge Pressure B. If discharge pressure is not within normal range,
Using the Operational Pressure Chart, page 64, deter- refer to the appropriate chart below.
mine if the discharge pressure is correct for the ambient
temperature the ice machine is located in. C. Record findings on Refrigeration Diagnostic Chart,
page 71.
A. It discharge pressure is within normal range,
proceed to Step 5B to analyze suction pressure.
DISCHARGE PRESSURE HIGH
Eliminate possible problems in the order listed on chart and follow appropriate corrective measures.
Possible Problem Actual Finding
Corrective Measure
1. Excessive load conditions
(air/water temperatures).
2. Dirty condenser.
3. Water regulating valve
(water-cooled condenser):
a. Too small supply water line.
b. Out of adjustment.
c. Defective regulating valve.
d. Dirty (scaled).
4. Fan motor/fan cycling switch
defective (air-cooled models).
5. Restriction in high side lines.
6. Headmaster Control Valve
defective (remote machines).
7. Improper refrigerant charge.
8. Noncondensables in system.
Relocate ice machine to location
| within guidelines (refer to
Installation Instructions).
Clean.
Replace with proper size line.
Replace.
Clean.
Diagnose control, page 46.
Repair, see Evacuation/Charging
Procedures, page 78.
Refer to Headmaster Control
Valve Diagnostics, page 72.
Refer to Evacuation/Charging
Procedures, page 78.
Refer to Evacuation/Charging
Procedures, page 78.
DISCHARGE PRESSURE LOW
Eliminate possible problems in the order listed on chart and follow appropriate corrective measures.
Possible Problem Actual Finding Corrective Measure
1. Load conditions low (air/water Relocate ice machine to location
temperatures). within guidelines (refer to
2. Water regulating valve (water-
cooled condensers):
a. Out of adjustment.
b. Leaking water during
harvest cycle.
c. Defective.
3. Fan motor/fan cycling switch
defective (air-cooled models).
4. Headmaster Control Valve
defective (remote machines).
5. Low refrigerant charge.
Installation Instructions).
Readjust/replace if necessary.
Replace.
Diagnose control, page 46.
Refer to Headmaster Control
Valve Diagnostics, page 72.
Continue through Six-Step
Procedures.
65
Step 5B — Analyze Suction Pressure
NOTE
Discharge pressures must be analyzed before suc-
tion pressure.
To analyze suction pressure you must compare the
Operational Pressure Chart, page 64, to the Cycle Time
Chart, page 64. The suction pressure gradually drops
as ice forms throughout the freeze cycle.
A. Normal suction pressure: proceed through
Six-Step Procedure. (Example: 33 psig after 9
minutes into the freeze cycle is normal at 90°F air
and 70°F water.)
B. Low suction pressure: Refer to Suction Pressure
Low chart, page 67. (Example: 12 psig after 3
minutes into the freeze cycle is considered low.)
C. High suction pressure: Refer to Suction Pressure
High chart below. (Example: 38 psig after 10
minutes into the freeze cycle is considered high.)
TIME IN MINUTES
Start of ! 2 3 4 > 6
| | |
| | | | |
Freeze 44 43 43 42 40 38
Cycle
| |
36 34 32 30 29 28
7 8 9 10 1 115 End of
| Freeze
Cycle
SUCTION PRESSURE
By comparing the two charts you can determine if
suction pressure is properly pulling down. Develop a
chart.as above and you will easily see where the suction
pressure should be compared to the amount of time the
ice machine is into the freeze cycle.
NOTE |
If the ice machine is located in other than 90°F air
and 70°F water another chart must be developed for
comparison purposes.
Example: G1200 self-contained, air-cooled:
air temperature 90°F
water temperature 70°F
From Cycle Time Chart, page 64:
freeze time — 10.0 to 11.5 minutes
harvest time — 1.0 to 2.5 minutes
total cycle time — 11.0 to 14.0 minutes
From Operational Pressure Chart, page 64:
Suction pressure:
start of freeze — 44 psig
end of freeze — 28 psig
SUCTION PRESSURE HIGH
Eliminate the possible problems in the order listed on chart and follow appropriate corrective measure.
Possible Problem
Actual Findings
Corrective Measure
1. High discharge pressure
affecting low side.
2. Hot gas valve stuck wide open.
3. TXV flooding.
4. Inefficient compressor (do not
perform pumpdown test).
5. Harvest pressure regulating
solenoid valve leaking
(remote machines).
See Discharge Pressure High,
page 65.
Replace valve, page 75.
Continue through Six-Step
Procedure.
Continue through Six-Step
Procedure.
Replace valve.
66
SUCTION PRESSURE LOW
Eliminate the possible problems in the order listed on chart and follow appropriate corrective measure.
Possible Problem Actual Findings Corrective Measure
2. Water area problem.
3. Tubing separating from
4. Plugged drier/restriction in
5. TXV is starving/low on charge.
1. Low load conditions.
backside of evaporator.
liquid line.
Relocate ice machine to location
within guidelines.
Refer to Step 4.
Replace evaporator.
Repair — refer to Evacuation/
Charging Procedures, page 78.
Continue through Six-Step
Procedure.
Step 5C — Hot Gas Valve Check
POSSIBLE PROBLEMS:
1.
Improper valve.
A hot gas valve requires a specific orifice size which
meters the proper amount of hot gas flow into the
evaporator during the harvest cycle. Replace defec-
tive hot gas valves with original Manitowoc replace-
ment (O.E.M.) parts only. Refer to your Parts
Manual for proper valve application.
Stuck in harvest cycle: Check for voltage at coil.
IF YES: Refer to Electrical Sequence of Operation,
page 22.
IF NO: Normally a hot gas valve can be repaired
without changing the entire valve. Rebuild or
replace the hot gas valve as required. Refer to
Refrigeration Solenoid Valve Replacement, page
75.
3. Leaking during freeze cycle.
a. Symptoms of leaking hot gas valve:
1) Ice production loss will be normal.
2) Ice fill on both evaporators will be normal.
3) Suction pressure at the end of the freeze
cycle will be slightly high. (This 1 to 4 psig
increase can be difficult to detect.)
b. Check procedures (Figure 64, page 68).
NOTE
Procedures must be performed twice, once for each
hot gas valve.
1) Feel hot gas valve inlet after 5 minutes
into freeze cycle.
A caution
HOT GAS VALVE INLET COULD BE HOT
ENOUGH TO BURN YOUR HAND. TOUCH IT
BRIEFLY.
2) Determine if the inlet of hot gas valve is hot
or close to compressor discharge line
temperature.
3) A good hot gas valve inlet line will be hot
to touch during the harvest cycle and be
cool enough to touch after approximately 5
minutes into the freeze cycle. With a
leaking hot gas valve, the inlet
temperature will remain close to the
discharge line temperature (hot to touch)
during the freze cycle.
Record your findings on the Refrigeration Component
Diagnostic Chart, page 71.
Hot Gas Valve Inlet Feel Check Findings: (circle one)
Compressor discharge temperature — Hot or Cool
Front hot gas valve inlet temperature — Hot or Cool
Rear hot gas valve inlet temperature — Hot or Cool
67
(=
NOTE: SELF-CONTAINED DIAGRAM SHOWN. CHECKS ARE THE SAME FOR REMOTE MODELS
HEAT FRONT REAR
EXCHANGE EVAPORATOR EVAPORATOR
== => ет ;
| i |
| | | |
' EXPANSION EXPANSION !
1 | I I
SUCTION LINE | | VALVE) VALVE | >):
FROM EVAPORATOR E SN TT
HOT GAS
HOT GAS VALVE CHECK SOLENOID VALVES
A TXV OPERATIONAL CHECK
~~ 5 MIN. INTO FREEZE:
FEEL INLET HOT GAS VALVE <— 5 MIN. INTO FREEZE:
| —o || COMPARE TEMPERATURES
COMPRESSOR DISCHARGE LINE AT INLET OF BOTH
EVAPORATORS
\ | AIR/WATER COOLED
| q 1 CONDENSER
NUE
1 ]
DRIER | DISCHARGE LINE | |
COMPRESSOR | |
. | |
RECEIVER
SV1104
FIGURE 64. HOT GAS VALVE INLET FEEL CHECK/TXV OPERATIONAL CHECK
Step 5D — Thermal Expansion Valve (TXV)
Checks
POSSIBLE PROBLEMS:
1.
68
Improper valve.
An improper valve will not achieve a uniform ice fill
on the evaporator or proper ice production under all
load conditions. Manitowoc O.E.M. expansion
valves use special bulb gas charges, port sizes and
stroke lengths to achieve this. Refer to the Parts
Manual for proper valve usage.
TXV not installed properly.
Refer to TXV Installation Procedures, page 74.
TXV starving or flooding.
It is extremely rare for two TXV's to fail at the same
time. When both TXV's are flooding or starving it
indicates that both valves are operating normally
and the symptom indicates trouble in another area.
A starving or flooding expansion valve may be
reacting to or trying to compensate for other
refrigeration problems. All conditions that could
cause a good TXV to starve or flood must be
eliminated. The following example emphasizes this
point:
An ice machine low on charge will cause both TXV's
to starve.
A service technician forgets to verify system charge
and changes both TXV's for starving.
While changing the TXV's the evacuation/charging
procedures are performed correctly, and the proper
charge put into the ice machine. The ice machine
functions properly and the technician thinks he has
diagnosed the problem correctly (bad TXV's). In
reality the problem was corrected because the
proper charge was put into the ice machine.
a. Symptoms of a starving valve:
1) Ice production will be low or ice machine
may not make ice.
se
2) The suction pressure will be lower than
normal.
3) The ice pattern (page 63) will be thin on top
and thick on bottom of evaporator fed by a
starving TXV and normal on evaporator fed
by a good TXV.
b. Symptoms of a flooding valve:
1) Ice production will be low or ice machine
may not make ice.
2) The suction pressure will be higher than
normal.
3) The ice pattern will be thick on top and thin
on bottom of evaporator fed by flooding
TXV and normal on evaporator fed by a
good TXV.
4. TXV operational check (Figure 64, page 68) is used
to determine how the TXV's are functioning. As
temperature readings must be accurate, a ther-
mocouple type of temperature meter is recom-
mended.
NOTE
Measure the inlet temperature of both evaporators
at least 5 minutes into the freeze cycle. Compare the
temperatures to each other.
a. Temperature indications:
1) Properly operating TXV's will maintain the
inlet temperatures within 5° of each other.
2) Anice machine with one good TXV and one
starving TXV will maintain the inlet
temperatures of the evaporators within 5° of
each other.
3) Anice machine with one good TXV and one
flooding TXV will not maintain the inlet
temperatures of the evaporators within 5°
of each other. This indicates the TXV
feeding the warmer of the two temperatures
15 a flooding TXV.
Record your findings on the Refrigeration Component
Diagnostic Chart (page 71).
Front evaporator inlet temperature
Rear evaporator inlet temperature
Step 5E — Compressor
1.
Suction valves (inefficient compressor).
An inefficient compressor can be hard to detect.
Components or problems that are not directly re-
lated to the compressor can simulate a faulty com-
pressor.
To diagnose a faulty compressor, systematically
check other components and rule them out one by
one, following the entire Six-Step Procedure. Step
6 will then indicate if a compressor change is
needed.
Symptoms of an inefficient compressor:
a. Reduced ice production will be noticeable at
lower ambient conditions and become more
pronounced as ambient temperatures in-
crease.
b. Ice fill pattern (both evaporators) normal at
lower ambients, although in extreme high am-
bient cases there may be little or no ice forma-
tion.
C. Suction pressures at the end of freeze cycle will
be slightly high and become more pronounced
as ambient temperature increases.
d. There may be intermittent flooding by the
TXV’s.
An inefficient compressor may “pump down” and
hold; therefore this type of test must not be used as
a determining factor for replacing compressors.
NOTE
2. Discharge valves.
a. The compressor shell will become hot and com-
pressor may cycle on overload.
Suction pressure will be high.
Discharge pressure will be lower than normal.
Check procedure for discharge valves:
1) Ensure compressor is running.
2) Turn ice machine off.
3) Immediately feel suction line — it will turn
hot if the discharge valve is leaking or
broken.
оо
69
STEP 6 — FINAL ANALYSIS
Thoroughly following the first 5 steps has eliminated all
nonrefrigerant problems. The Refrigeration Component
Chart will verify what is causing the problem.
Fill out the chart using the following procedures:
1. Based on the symptoms found while performing
Steps 1 through 5, fill in the Actual Findings column.
2. Each time the actual finding is the same as the
characteristic listed to the right of a step number,
put a check in the appropriate box. (Example: the
actual finding is “thin ice on top of evaporator.”) The
box under starving TXV is the only box checked
across the ice fill pattern section.
3. Add the number of boxes checked (under) each
component failure and put the total in the bottom
column. Refer to the component column with the
most boxes checked and follow the appropriate
procedures as listed in “a” through “d” below.
a. Hot Gas Valve Leaking column: Normally a
leaking hot gas valve can be repaired without
changing the entire valve. Rebuild or replace
the hot gas valve as required. Refer to
Refrigeration Solenoid Valve Replacement,
page 75. -
b. TXV Starving column: Verify the ice machine is
not low on charge before replacing both TXV’s.
Use the following guidelines:
By observing the ice fill pattern, change only the
TXV that is starving. If both TXV's are starving
the TXV's are most likely to be good and are
affected by some other malfunction such as an
ice machine that is low on charge.
70
A low refrigerant charge will affect both freeze and
harvest cycle pressures.
NOTE
С.
1) Add charge in 2 to 4 oz. increments to see
if the problem is corrected.
2) If problem is not corrected by adding
charge, change the TXV and drier. (Refer
to Evacuating/Recharging, page 78.)
3) If problem is corrected by adding charge,
find the refrigerant leak, change the drier,
evacuate and recharge, page 78. (System
must operate with proper charge — do not
leave run without changing drier, evacuating,
and recharging.)
TXV Flooding column: By observing the ice fill
pattern, change only the TXV that is flooding. If
both TXV’s are flooding go back through the
Six-Step Procedure to locate the cause.
Inefficient Compressor column: Replace the
compressor (and start components) and drier,
evacuate, and recharge, page 78.
To receive warranty credit on compressor, old start
components must be returned with faulty compres-
sor.
NOTE
Se
DUAL EVAPORATOR
ICE MACHINE REFRIGERATION COMPONENT DIAGNOSTIC CHART
This chart is used with a detailed outline of each of the Six Steps listed.
Failure to follow the details of each step in order will result in a misdiagnosis.
HOT GAS VALVE
LEAKING TXV TXV INEFFICIENT ACTUAL
STEPS (not wide open STARVING FLOODING COMPRESSOR FINDINGS
1. Visual Inspection Visual inspection includes checking for proper installation, location, dirty condensers,
etc., and talking to the ice machine user to identify the perceived problem(s). (Refer to
Step 1, page 61.)
2. Ice Production Normal ice 1. Low ice ice 1. Low ice 1. Minimal ice
production. production. production. production loss
2. Not making 2. Not making (almost normal).
| ice. ice. 2. Low ice
[ Po] | production. [|
3. Ice Fill Pattern Ice fill is normal on Ice fill will be thick Ice fill will be thin Ice fill is normal on Front
both evaporators. on the bottom on the bottom both evaporators.
portion of the portion of the
evaporator and thin | evaporator and Rear
on the top or no ice. | thick on the top or
| no ice.
4. Water System Water related problems can simulate a refrigeration component malfunction. Water
related problems must be eliminated before proceeding to Step 5.
5. Refrigeration System | Discharge pressure must be normal before proceding to Step 5B.
5A. Discharge Pressure | Refer to High/Low discharge pressure charts (page 65).
5B. Freeze Cycle Normal to 4 psig Lower than normal | Higher than normal | Slightly higher
Suction Pressures high at end of throughout freeze throughout freeze throughout freeze
freeze cycle. cycle. cycle. cycle. Pressures
normally do pull
down although
| take a long time.
SC. Hot Gas Valve Inlet | The inlet of hot gas The inlet of hot Front
Feel Check valve is hot and gas valve is cooler
approaches than discharge
temperature of line. Rear
discharge line.
5D. TXV Operational Evaporator inlet Evaporator inlet Evaporator inlet Evaporator inlet Front
Check temperatures temperatures temperatures not temperatures
within 5°F of each within 5°F of within 5°F: Warmer | within 5°F of each
other. each other. temperature other. Rear
indicates a
—
flooding valve.
Miscellaneous
—
—
—
—
—
6. Final Analysis
(number of boxes
checked)
71
HEADMASTER CONTROL VALVE
(Remote Machines)
Manitowoc remote systems require Headmaster Con-
trol Valves with special settings. Replace defective
Headmaster Control Valves only with “original”
Manitowoc replacement parts.
Operation
The R-502 Headmaster Control Valve has a non-adjust-
able setting of 185 psig (+ 10). At ambient temperatures
of 70°F and above refrigerant flows through the valve
from the condenser to the receiver inlet. At temperatures
below 70°F the Headmaster pressure control dome’s
nitrogen charge closes the condenser port. The bypass
port from the compressor discharge line opens. In this
mode the valve maintains minimum compressor head
pressure by building up liquid in the condenser and
bypassing discharge gas directly to the receiver.
Diagnosing Headmaster Control Valves
1. Determine air temperature entering remote con-
denser.
2. Determine if head pressure is low or high in relation-
ship to outside temperature (refer to Operation
Pressure Chart, page 64). If air temperature is
below approximately 70°F, the head pressure
should be modulating around 185 psig (+ 10).
3. Determine the temperature of the liquid line entering
the receiver by feeling with hand. This line is nor-
mally “body” temperature (warm).
4. Refer to Failure Chart to determine cause.
NOTE
An ice machine with a failed Headmaster Control
Valve that will not bypass will function properly with
condenser air temperatures of approximately 70° or
above. When the temperature drops below ap-
proximately 70° the Headmaster Control Valve fails
to bypass and the ice machine malfunctions.
Use the following procedure if the ice machine is
suspected of being low on charge:
1. Add refrigerant in 2-pound increments but do not
exceed 6 pounds
2. If the ice machine was low on charge the Head-
master Control Valve function and discharge pres-
sure will return to normal after the charge is added.
Do not leave ice machine operate; to assure opera-
tion in all ambient conditions the ice machine must
be evacuated and recharged with proper nameplate
charge.
If the ice machine does not start to operate properly
after adding charge, replace the Headmaster Con-
trol Valve.
HEADMASTER CONTROL VALVE FAILURE CHART
Possible Problem
Probable Cause
Corrective Measure
Valve not maintaining proper
pressures.
Non-approved valve.
Install O.E.M. Headmaster Control
Valve.
1. Discharge pressure extremely
high.
. Liquid line receiver feels hot.
Valve stuck in bypass.
Replace valve.
2
1. Discharge pressure low.
2. Liquid line entering receiver
extremely cold.
Valve not bypassing.
Replace valve.
—
a
Discharge pressure low.
2. Liquid line entering receiver is
warm to hot.
Ice machine low on charge.
Refer to procedures above.
72
HOW TO USE MANIFOLD GAUGES
Manifold gauges must be installed and removed proper-
ly to ensure no refrigerant contamination or loss occurs.
INSTALLING MANIFOLD GAUGES
2. Backseat (open) both high and low side service
valves at the ice machine.
3. With machine operating, read high and low side
pressures on gauges.
REMOVAL OF MANIFOLD GAUGES
G12SV065
FIGURE 65. INSTALLING MANIFOLD GAUGES
1. Connect high side line to high side service valve at
ice machine. See Figure 65.
2. Start low side line onto low side service valve at ice
machine. Do not tighten.
3. Open both high and low side valves on manifold
gauges. Be sure middle charging port is capped.
4. Backseat (open) high side service valve on ice
machine. Allow a small amount of refrigerant to
bleed from valve.
A
— A
a DL
G12SV066
Le
-
ur
[oes
IMPORTANT
Tighten low side line as refrigerant bleeds through.
This purges contaminants and noncondensables
from manifold and hoses.
READING OPERATIONAL
PRESSURES
1. Close both high and low side valves on manifold
gauge set.
FIGURE 66. REMOVAL OF MANIFOLD GAUGES
1. Run ice machine in freeze cycle.
2. Close high side service valve at ice machine.
3. Backseat (open) low side service valve at ice
machine.
4. Open both high and low side valves on manifold
gauge set. Refrigerant in lines will now be pulled
into the low side of system. Allow pressures to
equalize with ice machine still in freeze cycle.
5. Frontseat (close) low side service valve at ice
machine.
6. Remove hoses from ice machine and install caps.
NOTE
Removing manifold properly will ensure you do not
alter charge and will eliminate releasing C.F.C.'s into
atmosphere.
73
TXV INSTALLATION
Correct expansion valve installation is essential for
proper operation. Some key points to remember when
installing a valve include:
SOLDERING IN VALVE
Wrap the TXV with a wet rag or another heat sink. This
will prevent damage to the valve from overheating.
CAPILLARY TUBES
OFF TOP OF BULBS
INSULATE BETWEEN
SUCTION LINES SO
THAT BULBS AND
CLAM
SUCTION LINES LAMPS Ro NOT
LEAVING EVAPORATORS
SV1110
FIGURE 67. TXV BULB LOCATION
BULB LOCATION
1. Bulb must be clamped to a smooth, clean copper
tube, not to a weld joint.
2. The capillary tube of the TXV must come out of the
top of the bulb in a vertical position.
74
3. The bulb or the clamps holding the bulb must never
touch the other bulb or the clamps holding the other
bulb.
4. The outer edges of the clamps must be even with
the ends of the bulb.
BULB CLAMP LOCATION
All Manitowoc expansion valve bulbs are to be mounted
with two stainless steel screw clamps (Figure 67). Both
clamps must be used. Clamps must be flush with each
end of the bulb. Do not put both clamps in the middle of
the bulb, as this can cause the bulb to bow or warp.
BULB CLAMP TIGHTNESS
Bulbs must be tight for good thermal contact. A properly
tightened bulb will not move around the suction line
when twisted by hand. Properly tightened clamps may
slightly deform the bulb. This is normal and will not hurt
valve operation.
BULB INSULATION
1. The bulb insulation must be at least 3/8 inch thick.
If thinner insulation is used, apply additional layers.
2. Insulate between the bulbs before wrapping both
together.
3. Insulate the valve body to prevent sweating.
BULB INSTALLATION CHECK
To check if the bulb has good thermal contact, hold a
flashlight under the bulb and look for light between the
bulb and the suction line. If no light is seen, the contact
is good. If light can be seen between the bulb and the
suction line, the contact is poor, and the valve may
misfeed. The bulb must be retightened and/or moved
slightly and rechecked.
ALCO REFRIGERATION SOLENOID VALVES
(200 RB SERIES) REPLACEMENTS
The internal parts of Alco solenoid valves (200 RB
Series) are replaceable without changeout of the brass
body. Rebuild kit, Manitowoc part No. 24-0460-3, is
available for these Alco solenoid valves. The rebuild kit
includes the plunger, spring, O-ring, and piston assem-
bly. A solenoid valve which has a damaged seat or is
stuck open or closed can, in most cases, be repaired by
installing the rebuild kit. See Figure 68.
Use the following guidelines for warranty replacements.
1. Install rebuild kit when the enclosing tube and brass
valve body are not defective.
2. Replace the entire solenoid assembly when the
brass valve body is found defective or if the internal
surface of the enclosing tube does not permit
smooth plunger and piston operation.
3. Replace coil only when a coil malfunctions (open,
shorts, etc.).
NOTE
Starred (*) items are in the rebuild kit.
SPRING
APTO
COIL
ASSEMBLY
WAVE
WASHER ——m= ©)
(IF USED)
ENCLOSING —=
TUBE
*O-RING —_ >
*SPRING — — >;
*PLUNGER —— 57"
PE
"PISTON
ASSEMBLY
G6SV060
FIGURE 68. REFRIGERATION SOLENOID VALVE
75
LEAK CHECKING CONDENSER AND WATER
REGULATING VALVE
IMPORTANT
Both the condenser and water regulating valve must
be leak checked.
LEAK CHECKING CONDENSER
1. Set ICE/OFF/WATER PUMP switch at OFF.
2. Turn off incoming condenser water supply.
3. Disconnect incoming condenser water inlet and
outlet lines.
4. Disconnect water regulating valve from condenser.
5. Blow water out of condenser with compressed air.
Ensure refrigeration system is pressurized.
Leak check where cap tube meets the bellows
housing. See Figure 69.
Leak check around bellows seal.
Open valve by prying open at spring with screw-
driver, leak check inlet and outlet with leak detector.
If leak is detected, replace valve.
If no leak is detected, refer to NOTE under step 7 of
Leak Checking the Condenser and recheck valve
for leaks.
NOTE
Water in the condenser may cause an electronic leak
detector to give a false signal.
6. Ensure refrigeration system is pressurized.
7. Check condenser water inlet and outlet with elec-
tronic leak detector. If a leak is detected, replace
condenser.
NOTE
If no leak is detected with the ice machine off, set the
ICE/OFF/ WATER PUMP switch at ICE. Allow dis-
charge pressure to reach 250 psig, then set
ICE/OFF/ WATER PUMP switch at OFF and recheck
for leaks.
LEAK CHECK POINTS
G6SV062
LEAK CHECKING WATER
REGULATING VALVE
NOTE
Water regulating valve must be disconnected from
the condenser. Completely dry water valve inlet and
outlet to eliminate false readings from the leak detec-
tor.
76
FIGURE 69. WATER REGULATING VALVE
LEAK CHECK POINTS
REMOVAL FROM SERVICE/WINTERIZATION
You must take special precautions if the ice machine is
to be removed from service for extended periods or
exposed to ambient temperatures of 32°F or below.
A caution
IF WATER IS ALLOWED TO REMAIN IN THE
MACHINE IN FREEZING AMBIENT TEMPERA-
TURES, IT WILL FREEZE, RESULTING IN
SEVERE DAMAGE TO COMPONENTS. A FAIL-
URE OF THIS NATURE IS NOT COVERED BY
WARRANTY.
4. Hold valve open and blow compressed air through
condenser until no water remains.
5. Ensure no water is trapped in the water lines, drain
lines and distribution tube.
6. If ice machine is outside, cover machine to prevent
exposure to elements.
Self-Contained Air-Cooled Machines
1. Disconnect electric power at circuit breaker or
electric service switch.
2. Turnoff water going to ice machine.
3. Remove drain plug from water trough.
4. Disconnect drain line and incoming ice making
water line at rear of ice machine.
5. Blow compressed air in both incoming water open-
ing and drain opening in rear of machine until water
is no longer coming out of float valve and drain.
6. Ensure that no water is trapped in any of the
machine’s water lines, drain lines, distribution
tubes, etc.
7. If machine is outside, cover machine to prevent
exposure to the elements.
Water-Cooled Machines
1. Perform all procedures listed under Air-Cooled
Machines.
2. Disconnect incoming water line and drain line from
water-cooled condenser.
3. Pry open water regulating valve by inserting large
standard screwdriver between bottom spring coils
of valve. Pry spring upward to open valve, Figure
70.
INSERT SCREWDRIVER
BETWEEN BOTTOM
SPRING COILS AND
PRY UP TO OPEN
VALVE
G6SV063
FIGURE 70. MANUALLY OPENING WATER
REGULATING VALVE
Remote Machines
1. Frontseat receiver service valve, then pump down
ice machine. (Hang a tag on toggle switch as a
reminder to open receiver service valve on start-
up.)
2. Perform all procedures listed under “Self-Contained
Air-Cooled Machines.”
NOTE
Before putting a remote machine back into operation
after winterization, backseat the receiver service
valve.
77
EVACUATION AND RECHARGING
REMOVAL OF REFRIGERANT
Do not purge the refrigerant to the atmosphere. Recap-
ture refrigerant using recovery equipment by following
specific manufacturer's recommendations.
IMPORTANT
Manitowoc Ice, Inc. assumes no responsibility for
use of recycled refrigerant. Damage resulting from
the use of contaminated recycled refrigerant is the
sole responsibility of the servicing company.
EVACUATION AND RECHARGING
OF SELF-CONTAINED SYSTEMS
Before proceeding, determine severity of contamination
and clean-up procedures, page 82.
1. Replace liquid line drier.
IMPORTANT
TO PREVENT VOIDING WARRANTY, USE ONLY
MANITOWOC (O.E.M.) LIQUID LINE FILTER
DRIERS. |
2. Fully open service valves.
3. Evacuation of the ice machine requires connections
at two points as follows:
a. Suction service valve.
b. Discharge service valve.
Connect manifold gauges, dial-a-charge (or
weigh-in method), and vacuum pump to ice
machine, Figure 71.
NOTE
Install a two-stage vacuum pump to manifold
gauges. A single stage pump will slow the evacua-
tion process.
Procedures for Self-Contained Evacuation
IMPORTANT
Refer to refrigeration system Contamination Clean-
Up Procedures, page 82, for proper clean-up proce-
dures if system contamination is suspected or
detected. Improper or insufficient clean-up will lead
to repeat failures.
OPEN OPEN
TO TO
LOW SIDE HIGH SIDE
SERVICE SERVICE
VALVE VALVE
OPEN
1
CLOSED # X
GeSV064
FIGURE 71. EVACUATION OF
SELF-CONTAINED SYSTEMS
78
1. Place toggle switch in OFF position.
2. Open (backseat) high and low side ice machine
service valves. Open vacuum pump valve. Open
high and low side on manifold gauges. Refer to
Figure 71. |
3. Start vacuum pump. Pull system down to 250
microns. Allow pump to run for 1/2 hour after reach-
ing 250 microns.
NOTE
Turn off vacuum pump after 1/2 hour and ensure
pressures do not rise.
4. Refer to Recharging Procedures and recharge ice
machine.
Procedures for Self-Contained Recharging
IMPORTANT
Charge must be weighed or measured into ice
machine to assure proper operation under all load
conditions. Do not charge by sight glass, pressure,
etc.
1. Ensure toggle switch is in OFF position. Refer to
Figure 72 and recharge system.
ot
CLOSED OPEN 3. Open high side manifold gauge valve, backseat
high side service valve.
4. Open charging cylinder and add measured
nameplate charge through discharge service valve.
5. Allow system to “settle” for 2 or 3 minutes after
charging.
6. Place ice machine toggle switch in ICE position,
close high side on manifold gauge set, and add
remaining vapor charge through suction service
valve (if necessary).
CLOSED
7. Ensure all vapor in charging hoses is drawn into the
OPEN CO i ice machine before disconnecting manifold gauges.
G6SV065
NOTE
FIGURE 72. RECHARGING OF Recheck for leaks with a Halide or electronic leak
SELF-CONTAINED SYSTEMS detector after recharging ice machine.
2. Close vacuum pump valve, low side service valve,
and low side valve on manifold gauge.
HARYEST
REGULATING VALVE
VALVE
SV1001A
FIGURE 73. EVACUATION OF REMOTE SYSTEMS
79
EVACUATION AND RECHARGING
OF REMOTE SYSTEMS
Before proceeding, determine severity of contamina-
tion and cleanup procedures, page 82.
1.
Evacuation of remote systems requires connection
at four points for complete evacuation as follows.
Refer to Figure 73. |
a. Suction side of compressor through suction
service valve.
b. Discharge side of compressor through dis-
charge service valve.
c. Receiver outlet service valve. (Evacuates area
between head pressure control valve in con-
denser and pump-down solenoid.)
а. Access (Schraeder) valve on discharge line
quick connect fitting on outside of compres-
sor/evaporator compartment. This connection
is necessary to evacuate the condenser.
Without this connection, the magnetic check
valve would close upon the pressure drop
produced by evacuation prohibiting complete
condenser evacuation.
NOTE
3.
Open (backseat) high and low side ice machine
service valves, position receiver service vaive 1/2
open, and open high and low side on manifold
gauge set.
NOTE
If access valve core removal and installation tool is
used, remove discharge line quick-connect valve
core at this time.
Manitowoc recommends using an access valve core
removal and installation tool on the discharge line
quick connect fitting. The tool permits removal of the
| access valve core for faster evacuation and charging
without removing the manifold gauge hose.
NOTE
Install a two-stage vacuum pump to manifold
gauges. A single-stage pump will slow the evacua-
tion process.
Procedures for Remote System Evacuation
IMPORTANT
Refer to refrigeration system Contamination Clean-
Up Procedures, page 82, for proper clean-up proce-
dures if system contamination is suspected or
detected. Improper or insuffficient clean-up will lead
| to repeat failures.
1.
2.
80
Place toggle switch in OFF position.
Install manifold gauges, scale and two-stage
vacuum pump as shown on Figure 73.
4. Start vacuum pump, pull system down to 250
microns. Allow pump to run for 1 hour after reaching
250 microns. Turn off vacuum pump, ensure pres-
sures do not rise (standing vacuum leak-check).
Charge the ice machine per the following charging
procedures.
Procedures for Remote System Recharging
Refer to Figure 74 to connect cylinder or scale and
vacuum pump to recharge the system.
NOTE
Ensure toggle switch is in the OFF POSITION.
Close vacuum pump valve, frontseat (close) low
side and high side service valves, close low side
valve on manifold gauge set.
Add measured nameplate charge from charging
scale through high side of manifold gauge set into
system high side (receiver outlet valve and dis-
charge lines quick-connect fitting).
If high side does not take entire charge, close high
side on manifold gauge set, backseat (open) low
side service valve, and receiver outlet service valve.
Start ice machine and add remaining charge
through low side in vapor form until the machine is
fully charged.
Ensure all vapor in charging hoses is drawn into the
machine before disconnecting manifold gauges.
NOTE
Backseat (open) receiver outlet service valve after
charging is complete and before operating the ice
machine. If access valve core removal and installa-
tion tool is used on the discharge line quick-connect
fitting, reinstall Schraeder valve core before discon-
necting access tool and hose.
ee
7 VA 3)
= N
HEAT = =
EXCHANGER |
/ EVAPORATOR EVAPORATOR
PITT “LEY р г
| | ^ < 1 |
(cous
VALVES
| | | |
| | O | |
' AH
|
| (< L | |
| 4 " | |
| | | |
| |
| | | up J
LOW SIDE T TT
\ e mor я HOT GAS 4
FRONTSEATED SOLENOID
\, 7 | O VALVES —— O
„7 м w DISCHARGE LINE
7 | | QUICK CONNECT
COMPRESSOR SCHRAEDER FITTING
@ w A | CHECK VALVE
1 pump —
| DOWN | (HF
SOLENOID 7 REMOTE
E | CONDENSER
| > N À
HICH SIDE (7) deL IL _
| SERVICE VALE || N Г 1
N (FRONTSEATED) | |
| |
ı |
HARVEST PRESSURE / | В
REGULATING VALVE HPR | (
SOLENOID | >|
| |
RECEIVER | ( |
SERVICE VALVE | |
1/2 OPEN | |
v J ] |
MANIFOLD CONTROL
SET TEE
CLOSED OPEN
\
£5
CLOSED I
VACUUM
SCALE PUMP
OPEN
SV1001B
FIGURE 74. RECHARGING OF REMOTE SYSTEMS
81
SEVERE SYSTEM CONTAMINATION
GENERAL
It is important to read and understand the following text
regarding severe system contamination. The purpose is
to describe the basic requirements for restoring con-
taminated systems to reliable service.
IMPORTANT
Manitowoc Ice, Inc. assumes no responsibility for
the use of recycled refrigerant. Damage resulting
from the use of recycled refrigerant is solely the re-
sponsibility of the servicing company.
DETERMINING SEVERITY OF
CONTAMINATION AND CLEAN-UP
PROCEDURES
System contamination is generally caused by the intro-
duction of either moisture or residue from compressor
burnout into the refrigeration system.
Inspection of the refrigerant is usually the first indication
of contaminants in the system. If obvious moisture or an
acrid odor indicating burneut is present in the
refrigerant, steps must be taken to determine the
severity of contamination as well as the required clean
up-procedure.
If visible moisture or an acrid odor is detected, or if
contamination is suspected, the use of a Total Test Kit
from Totaline or similar diagnostic tool is recommended.
These devices read refrigerant, therefore eliminating
the need for an initial oil sample for testing.
If a refrigerant test kit indicates harmful levels of con-
tamination, or if the kit is not available, then inspect
the compressor oil as follows:
1. Remove refrigerant charge from ice machine.
2. Remove compressor from the system.
3. Check odor and condition (appearance) of the oil.
4. Inspect open suction and discharge lines at com-
pressor for burnout deposits.
5. Perform an acid oil test if contamination signs are
not evident per the above procedure to ensure no
harmful contamination is present.
The following chart lists findings and matches them with
required clean-up procedure. Use this chart for deter-
mining type of clean-up required.
CONTAMINATION/CLEAN-UP CHART
Symptoms/Findings
Required Clean-Up Procedure
No symptoms or suspicion of contamination
Normal evacuation and recharging procedures,
page 78.
Moisture/Air Contamination
(one or more of the following conditions will exist)
— Refrigeration system open to atmosphere for
prolonged periods
— Refrigeration test kit and/or acid oil test shows
contamination
— Leak in water-cooled condenser
— Oil appears muddy, or visible moisture in oil
Mild contamination clean-up procedures, page 83.
Mild Compressor Burnout
— Qil appears clean with acrid odor and/or
— Refrigeration test kit or acid oil test shows
harmful acid content
— No burnout deposits in open compressor lines
Mild contamination clean-up procedures, page 83.
Severe Compressor Burnout
— Qil discolored and acidic with acrid odor, burnout
deposits in compressor, discharge and suction
lines and other components
Severe contamination clean-up procedures, page 83.
82
he er”
/
MILD SYSTEM CONTAMINATION
CLEAN-UP PROCEDURES
1.
Replace failed components if applicable. If com-
pressor checks good, change oil in compressor.
Replace liquid line drier.
Follow normal evacuation procedure, page 78, ex-
cept replace the evacuation step with the following:
NOTE
If contamination is from moisture, the use of heat
lamps or heaters is recommended during evacua-
tion. Place heat lamps at the compressor, con-
denser, and at the evaporator prior to evacuation.
(Ensure heat lamps are not positioned too close to
plastic components such as evaporator extrusions,
water trough, etc., as they could melt, warp, etc.)
IMPORTANT
Dry nitrogen is recommended for this procedure to
prevent C.F.C. release into the atmosphere.
4
5
a. Pull vacuum to 1000 microns. Break vacuum
with dry nitrogen and sweep system. Pres-
surize to a minimum of 5 psi.
b. Pull vacuum to 500 microns. Break vacuum
with dry nitrogen and sweep system. Pres-
surize to a minimum of 5 psig.
c. Change vacuum pump oil. Pull system down to
250 microns. When 250 microns have been
achieved, allow vacuum pump to run for 1/2
hour on self-contained models, 1 hour for
remotes. A standing vacuum test may be per-
‚formed at this time as a preliminary means of
leak checking; however, the use of an elec-
tronic leak detector after the system has been
charged is recommended.
. Charge system with proper refrigerant to nameplate
charge.
. Operate ice machine.
SEVERE SYSTEM CONTAMINATION
CLEAN-UP PROCEDURES
1.
2.
3.
Remove refrigerant charge.
Remove compressor.
Disassemble hot gas solenoid valve. If burnout
deposits are found inside valve, install rebuild kit
and replace TXV. If contaminants are found replace
harvest pressure limiter control.
Check discharge and suction lines at compressor
for burnout deposits. Wipe out as necessary.
5. Sweep through open system with dry nitrogen.
Refrigerant sweeps are not recommended, as they
release C.F.C.’s into the atmosphere.
NOTE
Installation Procedures:
a. Install new compressor and start components.
b. Install an adequately sized suction line filter-
drier with acid/moisture removal capability and
inlet/outlet access valves. Place the filter-drier
as close to the compressor as practical.
c. Replace liquid line filter-drier.
Follow normal evacuation procedures, page 78,
except replace the evacuation step with the follow-
ing:
Dry nitrogen is recommended for this procedure to
prevent C.F.C. release into the atmosphere.
IMPORTANT
a. Pull vacuum to 1000 microns. Break vacuum
with dry nitrogen and sweep system. Pres-
surize to a minimum of 5 psig.
b. Change vacuum pump oil. Pull vacuum to 500
microns. Break vacuum with dry nitrogen and
sweep system. Pressurize to a minimum of 5
psi.
C. Change vacuum pump oil. Pull system down to
250 microns. When 250 microns have been
achieved, allow vacuum pump to run for 1/2
hour for self-contained models, 1 hour for
remotes. A standing vacuum test may be per-
formed at this time as a preliminary means of
leak checking; however, the use of an elec-
tronic leak detector after the system has been
charged is recommended.
8. Charge system with proper refrigerantto nameplate
charge.
9. Operate ice machine.
a. Check pressure drop across the suction line
filter-drier after 1 hour running time. If pressure
drop is not excessive (up to 1 psig differential)
the filter-drier should be adequate for complete
clean-up. Proceed to step 10.
b. If pressure drop is greater than 1 psig after 1
hour run time, change the suction line filter-drier
and liquid line drier. Repeat until ice machine
will run 1 hour without pressure drop. .
10. Remove suction line filter-drier after 43-72 hours
run time. Change liquid line drier and follow normal
evacuation procedures, page 78.
83
TABLE OF CONTENTS
GENERAL SPECIFICATIONS . . . . 20200020000 4 6 4 44e 4 ee eee
WARRANTY INFORMATION . . . ees
DIMENSIONS ©... ee ee
COMPONENT IDENTIFICATION . . . . . . . . 8 1400 as
Electrical Control Boxes . . ..... om... era ore ae ore eee ere rece»
Evaporator Compartment . . «cv tt ett tt ee ee eee ee ee ee eae ee ee eee eee
Air-Cooled Compressor Compartment . . . . . . . 222240404445 4 0 0 80 0 8 4 4 4 88 88 8 08088
Water-Cooled Compressor Compartment . . . . . . 2.424444 05004 4 4 4 4 68 0 88 888 88e 8e
Remote Machine Compressor Compartment ....... 2244040240 440 44 84808 0 88 68 08e
INTERIORCLEANING ................... aaa nera ae ore.
Removal of Parts for Cleaning . . . . ...oos. remera ae ae re rare rare e ree rre rm.
Remove Water Pump. . ....oereserede re orar errar ae rre naa rre arre.
Remove Float Valve . . ......o 2 e ade nee re ena rar e rene re reee ee rez
Remove Distribution Tube . . .....e.o eee e aaa aaa ae aaa.
Disassemble Distribution TUDE . . . . . 1... 122222 44440404 400 444044 646880 0080800
Remove се Thickness Probe . . ....eee. e. are ara ae redee a a eee e ere e rm 30
Remove Water Trough . . . ....eÑeo- se made aa eee reee ere rre ere
Cleaning Procedures . . ......orreeerer e erre reee
Cleaning the Evaporator .. ..... 224412244444 4 4 64 4 4 8 8 8 ков 8 884 0 888 88 ee
SANITIZING . ............ aaa ee adan roer oc rra orar
- CHECKING AND CLEANING THE WATER DUMP VALVE ............e. em...
) Operation Check .......e..o.rrerer redee eerere reee ererecrer
Remove Water Dump Valve . ....eox2reare ae aa aerea e e aerea re rre.
Disassemble Plastic Body WaterDump Valve . . . ....ei._oreeerroerrrre erre.
Disassemble Brass Body WaterDump Valve .... 2.240 120404 04404 44 4 0 8 0e 0 0 4 8 8436000
Cleaning Water Dump Valve .. .. 2.224 444244 LL 4444 4 4 4 4 4 8 4 4 0 ee 888 eee 855
ELECTRICAL SEQUENCE OF OPERATION — SELF-CONTAINED AIR OR
WATERCOOLED.............2 00412444 4 4 4 44 4 4 14 4 44 4 4 4 1 ea eee
Freeze Cycle (Prechill of Evaporator/Water Dump) . .. . . 4.120404 04 448444 4 48 4 4e 8e ee ee 0
Freeze CYyCIE 4 8 4 4 4 4 44 4 4 4e 44 4 eee ee ee eee
Harvest Cycle (No. 1). . .. 1.222 44424444 4 4 ee ee ee eee eee ee
Harvest Cycle (No. 2). . . . 112244444404 errada rea eee re reee
Harvest Cycle No: O
Harvest Cycle (No. 4). . ......i_eem.. 0000 re recrea e ae rere rear.
Automatic Shut-Off (Full Bin of Ice) ........ o... 0 ere eee reee
ELECTRICAL SEQUENCE OF OPERATION — REMOTE ICE MACHINES. .........
Freeze Cycle (Prechill of Evaporator/WaterDump) . . . . . . o.oo ooo oii viene к
Freeze Cycle .. .. 1.221214 444 44 44 ee ee ee ee eee eee ee
Harvest Cycle No: A aa aa ea aa ea amooo dae ne roo oran a e nena e ne a
Harvest Cycle (NO. 2) . . . . . oc i 0000 rare ree reee rre
Harvest Cycle (No. 3)... 0.00.0000 ee ee ee eee eee A 8e
Harvest Cycle (NO. 4) . . . . oo oo ee ee ee eee eee
Automatic Shut-Off (Full Bin of Ice) .......... ee
3-PHASE WIRING DIAGRAMS (208/230 V,3 Ph,5060Hz) ...................
3-PHASE WIRING DIAGRAMS (380/220 V,3Ph,50Hz) ..................... 35
WATER SYSTEM SEQUENCE OF OPERATION — SELF-CONTAINED OR
REMOTE MACHINES . . ...... 2.202... are ro deere ao one 36
Water System ....e...o. 0000000 a aa ae a een nea e e oe ener 36
REFRIGERATION SYSTEM SEQUENCE OF OPERATION — SELF-CONTAINED
AIR OR WATER COOLED ........ 22204144 44144 1 21111110 37
Prechill and Freeze Cycie . . ..... o. nerd odon ena re ae ea e eee or eee 37
Harvest Cycle... 1... 12222241 4 2 1 44 LL 4 4 LL 4 4 aero ra e ea ea e a e een a ae 38
REFRIGERATION SEQUENCE OF OPERATION — REMOTE ICE MACHINES ..... 40
Prechill and Freeze Cycle .......ío.o oc. ne dore aer re nera ra e ere ao ono 40
Harvest Cycle. .. .... 220202041111 4 424 4 4 4 4 4 4 4 40 4 ea eee e ae a 4 8 0 4 e ea era 41
Automatic Shut-Off .. . 1.122241 4 1 4 LL LL V4 2 4 4 eee aa a e ea eo e reee ea 43
SERVICE DIAGNOSTIC CHART ...... PT 44
COMPONENT FUNCTION, SPECIFICATIONS AND CHECK PROCEDURES ........ 46
Bin Switches . . . . 1.1. 2222124 42 42 4 4 2 4 4 e are nae a ae ee e ee ac rene. 46
Fan Cycle Control (Self-Contained Air-CooledModels) .. ... 2.222424 444440 42 re remo 46
Float Valve ... 1.21 424 44 4 2 4 4 2 4 LL 44 4 4 0 4 4 4 0 4 444 6 4 44 6 4 4 4 44 4 8 4 8 neo 47
High Pressure Cut-Out Control — H.P.C.O. 2... 22220244 4 4444444 eee aaa e 47
Ice Thickness Probe . . . . . . .. .. .. . e, ena deme ron e ea e ea e» e a e aa re 0 48
ICE/OFF/WATER PUMP Toggle Switch . . . ..... .. e... 2 2 erre are» ora a e e 0 48
Water Curtain . . . . . ........... ВЕ aaa 49
WaterPump ...... 224401 414444444444 4 0 4 ea ВЕ 49
Dump Valve Timer . . . . . 1.222444 44 44 4 444 448 4 4 4 444 4 4 8 0 4 0 8 4 4 2 8 0 0 0 ee 50
7-Second Delay Timer .. .. 1... 22222 1 4 4 4 4 4 1 4 4 e ae ea e nee aa e ea rea a e ena eo 51
Low Pressure Cut-Out Control (Remote Machines Only) . . . . . . . 20224 44 4 4 4 amare ooo re 52
Harvest Pressure Limiter Control (Remote Machines Only) . . . . 2.14 444424 4444 кк. 52
ELECTRONIC CONTROL CIRCUITRY . . . . . . 102000000110 4 4 4 4 4111111400 53 .
DIAGNOSING ELECTRONIC CONTROL CIRCUITRY . . ..................... 54
Ice Machine Will Not Go Into Harvest ...... 222024 4 4 4 4 444 4 4 4 4 4 44 44 4 4 4 4 4 1 4 0440 54
Ice Machine Prematurely Goes Into Harvest without Ice Formation . . . . .. 2244 44222 4 44 4 4 00 0 55
DIAGNOSING SINGLE (1) PHASE COMPRESSOR AND
START COMPONENTS ELECTRICALLY 1 L 11440 56
DIAGNOSING THREE (3) PHASE COMPRESSOR AND
СТАНТ СОМРОМЕМТ$У ЕСЕСТНЫЮСАМЦЮЕУ . ................... 2..5... ... 58
REFRIGERATION AND OTHER NON-ELECTRICAL PROBLEMS ............... 60
Introduction to the Six-Step Diagnostic Procedure .. . . . . 2.122204 4444 44 4 6 4 4 4 4 4 4 4 11120 60
Step 1 — Visual Inspection .. . 1... 2.220201 14 444 4 4 4 4 ema a aaa ea e a aa a ea e ez 61
Step 2 — Ice Production .... 1... 201020201444 44 44 4 4 4 4 V4 a ena ea e era e area 62
Step 3 — Ice Fill Pattern . .. . 1... 221202114424 4 4 4 4 4 4 4 4 4 2 4 4 4 4 4 4 a aa e aa ela a aro 63
Step 4 — Water System . . . . 1... 1 2111 1 2 1 4 LL 414 1 4 4 eo ae na e ea a a e aa 63
Step 5 — Refrigeration . .. . 1... 22202124 44 4 4 4 4 4 4 4 RR e a ae oa e ee a 64
Step 6 — Final Analysis .. . 222221244444 4 4 4 4 44 nene rra e eee a enema e 70
Headmaster Control Valve (Remote Machines) . . . . EEE н нон н НН н НН НН о 72
HOW TO USE МАМЕРОГО САЦСЕЗ .................... 2..5... к... 73
TXV INSTALLATION ............ 2... 2. к кк, 74
ALCO REFRIGERATION SOLENOID VALVES REPLACEMENTS . .............. 75
LEAK CHECKING CONDENSER AND WATER REGULATING VALVE . ........... 76
REMOVAL FROM SERVICE/WINTERIZATION . . . ... «ities 77
EVACUATION AND RECHARGING . . . HH 78
Removal of Refrigerant . . . . . 2... 22202044 4404444 eee eee eee ee 78
Evacuation and Recharging of Self-Contained Systems . . . . . . . . «cov cv von 78
Evacuation and Recharging of Remote Systems ......erereeererrerere ree. 80
SEVERE SYSTEM CONTAMINATION ........ o... ememeerrecee cera к 82
General... . .. on... m.rxeresderoa o e a rea re ae ada a aerea e ae e eee eee eee. 82
Determining Severity of Contamination and Clean-Up Procedures. . . . . . . . «ovo v ooo eve e ee 82
Mild System Contamination Clean-Up Procedures . . . . . . .. ee ee ee eae ees ee eee 83
Severe System Contamination Clean-Up Procedures . . .. . 240402405445 884 88e 3188 83
MANITOWOC ICE, INC.
2110 South 26th Street P.O. Box 1720 Manitowoc, WI 54221-1720
Phone: (920) 682-0161
Fax: (920) 683-7585
Web Site: www.manitowocice.com