Carrier 38GR Air Conditioner User Manual

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PO I N DL -
Air-Cooled C
A
4'-0" OVERHEAD SPACE REQUIRED
FOR SERVICE AND AIR FLOW
'-0"
AIR
” FLOW
CLEARANCE
A
38 GR
SUCTION LINE CONN $ DIAM HOLE
FOR CONTROL
LIQUID LINE WIRING
& -13" 14" DIAM
MTG SLOTS HOLE FOR
(USE ANY TWO) POWER
WIRING
SPACE REQUIRED FOR SERVICE
> CONDENSER AIR FLOW
(MIN DIM.,SQ OR TIE-DOWN BOLTS (4-20 x
| IN {USE ANY TWO
CIRCULAR) +
Ts LOCATIONS)
CONCRETE MOUNTING PAD* (SQUARE OR CIRCULAR)
*CONCRETE PAD SHOULD WEIGH 1-5 TO 2 TIMES WEIGHT OF UNIT
Fig. 1 — Dimensions, Connections
and Mounting Pad
Table 1 — Installation Data
38GR
CONDENSING UNIT 6527603 1004 1045 [005 | 0067
OPERATING WT (Ib) 151 1 170 | 182 1194 (234 | 260
DIMENSIONS {Diam A 2-5%
(Ft—in.) Height Bl2-412-412-412-412-e | 2-8.
REFRIG Sut ODEÍ % | % | % 1% | % 14
CONN. Иа ОБЕ и
*38GRO06 supplied with 3/4 to 1-1/8 in suction valve connection
adapter (field installed)
© Carrier Corporation 1972
—>
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PCIA
ondensing Units
a
+
This booklet includes wiring changes on 38GR
units starting from serial no. K200001.
TRANSPORTATION DAMAGE
File claim with shipping company if shipment 1s
damaged or incomplete.
PRELIMINARY SURVEY
Consult local building codes and National
Electric Code (NEC) for special installation
requirements.
When installing unit, allow sufficient space for
air-flow clearance, wiring, refrigerant piping and
servicing unit. Recommended minimum require-
ment is 3 ft (Fig. 1). Position unit so water from
roof or eaves Will not pour directly on top of unit.
Install unit on a solid, level mounting pad.
Position tie-down bolts in pad. Any two holes in
unit base may be used to fasten unit to pad.
38GR Condensing Units Connected to Carrier
Approved Evaporators with Carrier Accessory
Tubing — 38GR units contain correct refrigerant
charge when evaporator is same size, or one size
larger than condensing unit and are connected with
Carrier accessory tubing. Check refrigerant charge
when tubing lengths are above 50 feet. See
Refrigerant Charging for details.
38GR Condensing Units Connected to Non-Carrier
Evaporators — Check refrigerant charge when the
38GR is added to a system in which other than a
Carrier approved evaporator is being used or where
the evaporator has been previously installed. Field-
supplied refrigerant piping must be in accordance
with Refrigerant Piping Data table. Where evap-
orator is below condensing unit, reduce liquid line
size one diameter (min 1/4-in. OD).
PIPING CONNECTIONS
38GR condensing units can be connected to
evaporator sections using Carrier accessory tubing
package or field-supplied tubing of refrigerant
grade. (Accessory tubing not available for
38GR006.) See Table 2 for accessory tubing sizes
and Table 3 for recommended field-supplied tubing
sizes. Do not use damaged or contaminated tubing.
Do not use less than 10 ft of liquid line. Do not cut
5/16-in. or 1/4-in. liquid line. Bend or coil to fit.
If accessory tubing package or evaporator sec-
tion has been open for more than 15 seconds per
connection, evacuate or purge evaporator coil and
tubing system (use field-supplied refrigerant, not
unit refrigerant). If necessary, refer to Carrier
System Design Manual, Part 3, for standard piping
techniques.
Form 38GR-3S1
Connection Procedure — When making piping con-
nections, be sure to provide clearance at unit for
electrical connections.
Connect refrigerant liquid and suction lines to
condensing
unit (Fig. 1). Unit compatible fitting
permits two methods of refrigerant line connec-
tion:
mechanical
(quick connect) or sweat
connection.
38GR0O06 UNITS — Remove suction line adapter
taped to compressor suction line and connect to
suction line compatible fitting. Sweat connect
refrigerant
refrigerant
HHOTADO40
HH93AZ040
HH51AROO1
HHO7AT 070,
HHO7AT074
HH93AZ076
HHO1AD042
HH93AZ042 |
HHO1Y A092 |
HH93YZ094
32LM001-301
gn on wr we
suction line to adapter. Connect liquid
line to unit.
Table 2 — Accessories
DESCRIPTION
LTC NA SER CEASE GE, о
Low- Voltage Control - Honeywell Deluxe
Thermostat
Thermostat Subbase
Comfort Control Center (Use wi th HHO1 AD040)
Low-Voltage Control - Honeywell Thermostat
Thermostat Subbase (with Automatic
Chongeover)
Sr AAPA ti O E E ain A AA pt era tre
Low- Voltage Control - Honeywell Thermostat
| Thermostat Subbase
a nar N MEERE
Low- Voltage Control - Grayson Thermostat
Thermostat Subbase _
Solid State Head Pressure Control
Special field-installed fan motor required
[rep
| Unit | 38GR002,003,004,045] 38GR005,006
Motor HC38VE851 HC40V 1701
'38GC900-1 52
Indoor Fan Fan Relay (Six - 38BA400693)
| [Tubing Packages (not available for 33GRO06).
Packages have 3/4-in, suction line and
3/8-in. liquid line Suction line is insulated
and has a 90° bend on one end
MECHANICAL CONNECTION (Mate one: set of
connections at a time).
1. Loosen nut on compatible fitting one turn. Do
not remove.
2. Remove plug and be sure O-ring is in the groove
inside the compatible fitting.
3. Cut tubing to correct length.
Use gage on tag attached to service valve to
mark tube end for correct insertion depth.
Insert tube into compatible fitting until it
bottoms. (Tube should be inserted at least as
far as mark on tubing.)
5. Tighten nut until it bottoms on back coupling
flange.
SWEAT CONNECTION (use refrigerant grade
tubing).
1. Remove locking nut, rubber O-ring and Schrader
core from valve.
2. Cut tubing to correct length.
3. Insert tube into compatible fitting. Wrap top
and bottom of service valves in wet cloth to
prevent damage by heat.
temperature (450 F) silver alloy solder.
Replace Schrader core.
Solder with low-
5. Evacuate or purge system with field-supplied
refrigerant.
SERVICE DOOR
Service door can be opened or removed for
wiring or servicing unit.
Remove three screws from left side of service
door (Fig. 1) to swing door open.
Door Removal — Ensure power is off. Disconnect
wiring from control panel which is mounted on
386C900071 |10 ft Пес ol
38GC900081 {18 fi door. Refer to Fig. 4 and 5. After wiring is
38GC900091 [25 fr disconnected, lift door from roll pin hinges.
38GC900101 135 ft
38GC900111 |50 fr
Table 3 — Refrigerant Piping Data
| MAX COND E. REFRIGERANT L LINE LENGTH (ft) |
COND | REFRIG | UNIT HT (ft) | 25 | 50 75 | 100 pa
UNIT | CONTROL | Above| Below| ~~ Line Diameter (in. OD) В _-
Evap | Evap | Suction | Liquid | Suction Liquid Suction | Liquid | Suction | Liquid | Suction | Liquid
TXV 90 90 ;
- 4 % 3 3 Y, % % % % Y
38GR002 Cap. Tube | 70 50 ‘ * a * © EE 6
- XV | 90 9 |, E a
HAV LIE LY y 3 3 3, 3, y % % y
38GR003 Cap. Tube 70 50 4 6 7 4 In в 4 | > | 8 о
TXV 90 90
R ane ен i 3 3 Y, % % % % Y % Y,
MN Cop Tube | 70 | | * 4 A ALE AL A PAL A
TXV 70 90 3 3 3 1 7 1 7 7
UD a ZE / L Y и
38GR045 Cap Tube 70 so 7a 1 A 7 6 % 8 a 8 2
9
38GR005 Top Te — = = % % % % % % % % 1% %
“38GROO6 | TxV 90 90 | 1% % 14% % | 1% % | 4 % 1% %
Cap. Tube — Capillary Tube TXV — Thermal Expansion Valve
®
2
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ELECTRICAL DATA AND WIRING
Table 4 — Electrical Data
HE ane HH. AA EMA ra RAEN KETONE te
COMPR [FAN
COND
UNIT — УРА | ОКА ЕСА ЕСА
(AWG)
38GR002-- 614281101178
38GR002310 72 04 8 | 10
З8СВ003--- 900119 2 [1 1
38GR0033 10 900019 2 | 11
38GR004--- [230/11100 01229 | 1 3
38GR0043 10 1000229113
38GR045__. 108 0126 9 | 1 3
38GR005-_- 118030 4120
38GR006… 155.0 39.0 | 2.0
38GR003.__ 60 0130111
38GR0034 10 700130111
38GR004___ 69 01140 (1 3
386R004410 1200/3| s0 O 14 0 113
38GRO45 870140113
38GRO05 90 01186 20
386R006--- | |10.0 23.0 |2.0 |
38GR003-_- 50001511 1
38GR003516 600011 51 1
38GRO04 600126113
38GR004510 1230/31 70 01126 113
38GR045—-- 370124113
38GR005-—— 785161120
38GR006-—-| __ [100.0 20.5 | 2.0
38GR004 300] 65] 7
38GRO04610 355016517
38GR045--- 1460/31 46 0162 | 7
38GRO005-.. 39 3183112
38GR006___ 50 0h03 |1 2
| Corresponding wire sizes and wire lengths
FLA — Full Load Amps
LRA — Locked Rotor Amps
— — — Electrical data shown applicable to all units for which
complete model numbers are not shown Example:
38GR003 applies to all 003 models except 33GR0O03570
— —= —
*Copper wire sizes and lengths Use latest National Electric Code (NEC)
for aluminum wire sizing
{Maximum dual element fuse size
NOTES
1 Motors and controls will operate satisfactorily from 10% above to
10% below unit voltage Control circuit voltage is 24 volts on all
units On 3-phase units, phases must be balanced within 2%
2 Nominal Distribution System Voltage (NDSV) is 240 v for 230 v,
1-ph units; 208 v for 200 v, 3-ph units; 220-240 v for 230 v, 3-ph
units; 440-480 v for 460 v, 3-ph units
Wiring and electrical information below pertain to
current 38GR units from serial no K200001. Field
wiring must comply with local and national codes.
Install a branch circuit fused disconnect of
adequate size to handle starting current. When
making electrical connections, provide clearance at
unit for refrigerant piping connections.
LINE POWER wiring is brought thru hole provided
in base pan (Fig. 1) and into unit junction box,
Fig. 5. Splice line power leads to brown and orange
pigtails on l-phase units, or brown, orange and
black pigtails on 3-phase units. See Fig. 2. Use wire
nuts supplied with unit. When aluminum field wire
is used, lubricate splices with splice compound
(also supplied) before using wire nuts.
CONTROL POWER (24 v) wiring is brought thru
hole provided in unit base pan (Fig. 1) and into
low-voltage section of unit junction box. Splice
control leads to yellow pigtails on control relay.
See Fig. 3, Use wire nuts supplied with unit. When
aluminum field wire is used, lubricate splices with
supplied splice compound. Furnace or fan-coil
transformer must be used as 24-v supply for system
as shown in Fig. 3. Current 38GR condensing units
(from serial no. K200001) are equipped with
transformer used to power contactor thru unit
control circuit.
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Piotr CT,
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Fig. 2 — Line Power Connections
START-UP INSTRUCTIONS
Energize crankcase heater a minimum of 4
hours before starting unit.
Start Procedure
1. Backseat (open) liquid and suction line service
valves.
2. Close electrical disconnects energizing entire
system.
Set room thermostat to desired temperature.
4, Set room thermostat to “Cool” and fan switch
as desired (“Fan”) (““Auto.””). Unit will start in
4 to 6 minutes. Operate unit for 15 minutes,
then check system refrigerant charge. See Re-
frigerant Charging.
w
Motors and controls will operate satisfactorily
in a range from 10% above to 10% below nominal
unit voltage (Table 4).
Do not connect charging hoses to capillary-
controlled system during initial start procedure.
(Loss of charge from this procedure may result in
capacity reduction.) If necessary to add manifold
gages for servicing, refer to Carrier Standard
Service Techniques Manual, Chapter 1, pages 1-5,
Fig. 8, for bypass method of returning charge to
system.
Table 5 — Service Data
R-22 | _. . CONDENSER FAN _.
UNIT CHG* | _ Rpm_ | Diam | Ст
| (Ib-0z) | Hi Lo | (in) | Hi | Lo.
_38GR002 | 5-10 | 1050 | 850| 20 | 2800 | 2300
. 38GR003 | 5.6 1 10501 850, _20 2800 1 2300
_.38GR0O04 | 6 5 | 1050 1 850 |. 20 _} 3100 | 2600
— 386R045 : 6- _ 1050.| 850 20. … 3100 | 2600
_ 386К005 | 6-10 … 1070 _8/0}. 20 .1.3700.4_3200.
38GR006 6-10 | 1070 | 870 20 3700 | 3200
I Aa, ie He teo cc
*Factory refrigerant charge adequate when condensing units are
connected to Carrier approved evaporators that are the same
size as (or one size larger than) condensing unit with Carrier
accessory tubing See Refrigerant Charging for details
THERMOSTAT SUBBASE
HH93AZ042 OR
THERMOSTAT SUBBASE
HH93AZ042 OR
HH93AZ040 Po See | ..HH93AZ040
\ |
| |
- MM le
m J | —
[Rh r- - LN Yer | [RH ONE
nec + [Y}— ln
[61+
|
|
TRANS | al
>= 14 WE—-
Clg
CR
FS
HC
Htg
IFM
“applications
ARRANGEMENT A-
(COOLING ONLY)
THERMOSTAT SUBBASE
HH93AZ
076
RH = + — — — — — — met re о 220020 — ——
F— JUMPER ON
SUBBASE (RH TO RC)
applications, locate (IFR) in fan coil
— Cooling
— Control Relay (10 va)
— Fan Switch
— Heating Control
— Heating
— Indoor Fan Motor
= (VOLTAGE
POWER
SUPPLY
3
т
=
E
=
m
ARRANGEMENT C-
ONE TRANSFORMER
(COOLING AND TWO-STAGE HEAT)
*CONNECT FS TO LOW-SPEED INDOOR FAN TERMINAL
WHEN TWO-SPEED FAN IS USED
EZ IFR, FS and IFM are located in furnace on heating-cooling
If accessory IFR is required for cooling only
IFR —
aa -
Г 38GR |
|
| A |
| me — YEL (CR) |
_ | }
= == == — — — — — == — — — = J river |
= ) TO IFM LINE + |
= | VOLTAGE | i |
POWER | | |
SUPPLY I | |
| |
|
La |
| |
L TRANS |
| YU — 1
FURNACE
ARRANGEMENT B-
ONE TRANSFORMER
(COOLING AND ONE-STAGE HEAT)
*CONNECT FS TO LOW-SPEED INDOOR FAN TERMINAL
WHEN TWO-SPEED FAN IS USED
ae
1
TRANS
IT
| ООО ООО ООО ООО ОО ОАО “Ноа = 74
FURNACE
ER
Indoor Fan Relay
Trans — Transformer
=
—
Field Splice
Field Wiring
Factory Wiring
Fig. 3 — Control Circuit Connections
4
UNIT PROTECTION
»
High-Pressure Relief Valve is located in compres-
sor. Relief valve opens at a pressure differential of
approximately 450 — 550 psi between suction and
discharge. Valve permits pressure equalization at
running condition described above and during unit
shutdown. A hissing sound during pressure equali-
zation does not indicate bad valves.
High Pressurestat is located on unit liquid line and
has black leads. High pressurestat settings are:
cutout, 425 + 5 psig; cut-in, 320 * 20 psig.
Low Pressurestat is located on unit suction line and
has blue leads. Low pressurestat settings are:
cutout, 31 + 4 psig; cut-in, 60 + 15 psig — O psig.
Internal Compressor Thermostat resets auto-
matically when internal motor temperatures drop
to a safe level (thermostat may require up to 30
minutes to reset). When internal thermostat is
suspected of being open, check by using an
ohmmeter or continuity tester. If necessary, refer
to Carrier Standard Service Techniques Manual,
Chapter 2, for complete instructions.
Outdoor Fan Thermostat switches fan to high
speed (Table 5) when outdoor temperature reaches
90 F — maintains proper condensing temperature
at high outdoor air temperatures. Thermostat is
located on Control Panel, Fig. 4.
Filter-Drier is installed in liquid line.
Compressor Protection Control System (CPCS —
Solid State, Fig. 4) provides: compressor motor
locked rotor protection; compressor start winding
protection; compressor motor running overload
protection; compressor overtemperature protec-
tion; contactor anti-chatter protection.
The CPCS also provides for a 4- to 6-minute
delay before restarting compressor after shutdown
for any reason. If compressor loading was light at
the moment compressor was shut off, the delay will
be approximately 4 minutes. If loading was heavy,
the delay will be approximately 6 minutes. The
CPCS board is located on control panel beneath a
sheet metal protective cover. To troubleshoot the
CPCS, remove protective sheet metal cover, and use
unit label diagram or wiring booklet with Control
Circuit Troubleshooting Chart, page 6.
—~ CONTROL CIRCUIT TROUBLESHOOTING
CHART NOTES:
1. Ensure thermostat calls for cooling before
troubleshooting unit.
2. To disconnect plug from receptacle on CPCS
board — press in tabs located on the receptacle,
and pull plug gently while holding tabs. Do not
pull on wiring.
un
3. Receptacle female connections, which do not
grip the male pin tightly, may be repaired with
a small pen knife.
4. When taking meter readings at CPCS receptacle,
bottom meter probe into terminal hole to
ensure good electrical contact.
5. Replace CPCS board if electrical short circuit
causes compressor failure. An electrical short in
compressor can short the triac (electronic
switch located on CPCS board). Triac may fail
in a closed (conducting) position and will not
open the control circuit.
COMPRESS
PROTECTIO
CONTROL
SYSTEM
BOARD
(CPCS)
FAN THERMOSTAT
{IF SO EQUIPPED)
fé,
SINO =
a me
К Во e
E
MT - Pn ali +
а , Me Po
a i
IN od ed
CURRENT
ARE
Fig. 4 — Control Panel (Cover Removed)
COMPRESSOR REMOVAL
See Table 6 for compressor information and
Fig. 5 for component location.
1. Shut off power to unit. Vent refrigerant to
atmosphere or use refrigerant removal methods
shown in Carrier Standard Service Techniques
Manual, Chapter 1.
2. Remove unit top cover (grille). Open or remove
service door.
3. Disconnect fan motor leads (4) from control
panel located on service door. See Fig. 4 and
refer to Service Door on page 2. Remove 6
screws holding fan motor orifice assembly in
place and lift assembly from unit.
4. Compressor sound shield is fastened to tube
sheets with 4 screws and to base pan with 3.
Loosen screws and remove sound shield by
sliding it straight up using tube sheets as guides.
5. Remove power leads from compressor terminal
box. Unsweat suction and hot gas lines.
6. Remove compressor hold-down bolts. Lift com-
pressor out thru top of unit,
CONTROL CIRCUIT TROUBLESHOOTING CHART
ab ALA,
CT a e e ee re aa ee ae ree reee ese e ee ee eee ere rt rey
MD te e aaa eee rara era ee eee e aerea eee e e ee e e
Before attempting any corrective action, wait 8 minutes after power is supplied to permit CPCS time delay period to end. \f control circuit is
broken and unit has no time delay (or if time delay is over 8 minutes), replace CPCS board
IMPROPER UNIT OPERATION => CONTACTS CLOSE CPCS Board and control circuit func- С
STEP 1 - {MMEDIATELY, UNIT —- | tion Check compressor, run capacitor,
DOES NOT RUN start gear and internal compressor
Check contactor operation Г protection
l—» CONTACTS WON'T STAY
CLOSED OR OPEN BE- Check system pressures and current
FORE ROOM THERMO-">"| draw
STAT IS SATISFIED
CONTACTS NEVER CLOSE
STEP 2
Y CONTACTOR
Te]
Check unit voltage at terminals VOLTAGE LOW OR Obtai + |
21 and 23 on contactor > NO VOLTAGE ——>- | Obtain correct voltage
VOLTAGE CORRECT
STEP 3
Check control circuit and current transformer wiring and p= LOOSE CONNECTIONS щи |
connections OR IMPROPER WIRING Repair connection or correct wiring
1
WIRING AND CONNECTIONS GOOD
STEP 4
Check output at 5 va secondary CURRENT TECEDTACES
of unit voltage transformer (at -——— VOLTAGE LOW OR
terminals 2 and 10 on CPCS re- | printeo! 14 3 T7 NO VOLTAGE —> | Replace transformer |
ceptacle) Should be 23-30 PRINTED [16 5
| CIRCUIT
volts | _ 8 7
a lo 9
I
BOARD VOLTAGE CORRECT
STEP 5*
Check output at 25 va secondary of unit voltage transformer >
(at CPCS receptacle termina! 3 and Cy on contactor) Shoutd Ме АСЕ, OR — | Replace transformer |
be 23—30 volts
VOLTAGE CORRECT |
STEP 6*
Check contactor voltage at C4 and C7 terminals on con-jL “XX.
tactor (6) Should ba 23-90 volte VOLTAGE CORRECT —» | Replace contactor |
NO VOLTAGE
STEP 7*
Check control circuit voltage from contactor (C) terminal — > VOLTAGE IS LOWER Check indoor unit power, indoor
Co to terminal 1 on control relay Should be 20-29 volts THAN 20 VOLTSY > transformer, thermostat or control
relay
VOLTAGE CORRECT
STEP 8*
Check control circuit voltage from contactor (C) terminal
Ca to junction of high-pressure switch (HPS) and low- — VOLTAGE 1S LOWER System pressure too high or bad high-
pressure switch (LPS) Should be 20—29 volts THAN 20 VOLTST pressure switch
VOLTAGE CORRECT |
STEP 9*
Check control circuit voltage from contactor (C) terminal --— VOLTAGE IS LOWER System pressure too low, bad low-
Cn to terminal 8 on CPCS receptacle Should be 20—29 volts THAN 20 VOLTS , pressure switch or open internal pro-
tector (IP)
VOLTAGE CORRECT
STEP 10
| Replace CPCS board
* Ly Lo TYPICAL CONTROL CIRCUIT INDOOR UNIT TRANSFORMER
THERMOSTAT
(COOLING)
Г)
PS LPS P
Der ON 0-96
О CR — eee, TRIAC
CPCS Receptacle IF SO EQUIPPED
Component Connections
+ Voltage reading less than 20 volts may result from feedback circuit 6
x
TIA
1.
=
Table 6 — Compressor Data
PRODUCTION | OIL RECHARGE
COND UNIT | V/PH | COMPRESSOR* (oz)
38GRO02: 3861 400324 40 5
38GR0023 10 MD2723CB 43 2
38GR003--- 38GR400234 315
38GR0033 10 MC3423CB 43 2
38GR004--- | 230/1*| 38GC401564 45 0
38GR004310 MC4023CB 43 2
38GR045__- 48D 400794 45 0
38GR005. RC5425C 72 0
8GR006_ - RC7025CT 720
38GR003. RF3522C 50 4
38GR003410 MF3423CB 43 2
38GR004--- RF3922CJ 50 4
38GR004410 | 200/3 | MF4023CB 43 2
38GR045_—- 48DL 400804 45 0
38GR005--- RF5425CJ 72 0
38GR006-—— RF7025CJ 72.0
8GRO03..- RG3522C J 50 4
38GR003510 MG3423CB 43 2
38GRO004-—- RG3922C 50 4
38GR004510 | 230/3 | MGA4023CB 43 2
38GR045--- 48DL 400804 45 0
38GR005--- RG5425C) 72 0
8GR006- RG7025C 720
38GR004- RH3922CJ 50 4
38GR004610 MH4023CB 43 2
38GRO45--- | 460/3 | 48DL400814 41 4
38GR005--- RH5425CJ 64 8
38GRO06-—. RH7025C1 64 8
*All 38GR single-phase compressors are capacitor start Refer to
Service Parts Catalog for replacement compressor model
numbers
——-Tabular data shown applicable to all models except those
shown italicized 000.
TOP GRILLE COVER
FAN MOTOR-ORIFICE
ASSEMBLY
SERVICE
DOOR
SOUND
HOT GAS SHIELD
LINE COMPRESSOR
TERMINAL
SUCTION
HE JUNCTION
COMPRESSOR BOX
DISCONNECT
WIRING TO
REMOVE
SERVICE DOOR
SUCTION VALVE
SERVICE PORT
LIQUID VALVE
SERVICE PORT
Fig. 5 — Condensing Unit with Service Door Open
PUMPDOWN PROCEDURE
The 38GR units may be pumped down in order
to make repairs on low side of system without
losing complete refrigerant charge.
. Attach pressure gage to suction service valve
age port.
2. Frontseat the liquid line valve.
3. Jumper low-pressure switch.
4. Start unit and run until suction pressure reaches
5 psig (see Caution).
5. Shut unit off and frontseat suction valve.
6. Vent remaining pressure to atmosphere.
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REFRIGERANT CHARGING
38GR units contain correct operating charge
for complete system when connected to Carrier
approved evaporators that are the same as (or one
size larger than) condensing unit, with Carrier
accessory tubing. For every 10 ft of liquid line of
recommended size over 50 ft, add refrigerant
charge as follows: .7 Ib for 1/2-in. line, .4 16 for
3/8-in. line, 1.1 1b for 5/8-in. line. Charge adjust-
ment may be required on other systems.
To check or adjust refrigerant charge on all
Carrier approved systems, use a Carrier Charge-
master® (Part no. 38GC680004) for capillary tube
or AccuRater™ systems and Charging Chart
Method for thermal expansion valve systems.
To recharge these systems, use Weight Method
when evaporator is same size or one size larger than
condensing unit, and they are connected with
Carrier accessory tubing; Chargemaster for remain-
ing Carrier capillary tube or AccuRater systems and
Charging Chart Method for remaining Carrier ther-
mal expansion valve systems. When 38GR condens-
ing unit is connected to other than a Carrier evap-
orator, use Weight Method or Sight Glass Method of
recharging.
Evacuate 38GR systems to 5,000 microns
(29.7-in. vacuum) before recharging. Refer to
Carrier Standard Service Techniques Manual,
Chapter 1, for system evacuation-dehydration
instructions and details of charging instructions
listed below.
ий
tte
.
+
КОННЫХ
Charging Chart Method — Use Charging Chart, Fig.
6 or 7. See Carrier Standard Service Techniques
Manual, Chapter 1, for procedure.
Weight Method — Refer to Table 5 or unit
nameplate for correct system refrigerant charge.
Blow any refrigerant remaining in system before
recharging.
When system is not evacuated, subtract the
following amount from total charge:
38GR0O02 — .10 1b (1.6 07) |
38GR003,004,045,005,006 — .20 1b (3.2 07)
Keep refrigerant recharge within one oz of
specified charge on 38GR002 systems and within 2
oz on 38GR003,004,045,005,006 systems.
Dial-a-charge charging cylinder is an accurate
device used to recharge systems by weight. These
cylinders are available at refrigeration supply firms.
Chargemaster® Operation — Operate unit 10
minutes before using Chargemaster (Carrier Part
no. 38GC680004).
1. Tape Chargemaster feeler bulb to suction line
close to condensing unit. Insulate bulb. Ensure
suction line is clean for good contact with bulb.
2. Connect refrigerant drum to Chargemaster inlet
port with drum in position for vapor charging.
3. Connect Chargemaster outlet port to unit
suction valve service port.
4. Crack valves on refrigerant drum and Charge-
master to purge lines from drum to suction
valve. After purging lines, close valve on Charge-
master only.
5. Measure outdoor air dry-bulb temperature.
6. Crack unit suction valve and read evaporator
temperature at red needle position on Charge-
master temperature gage and suction line tem-
perature at black needle position.
door air temperature (step 5) and evaporator
temperature (step 6). Find the suction line
temperature required for correct system charge. —
If actual suction line temperature (step 6) is
higher than table value, the system is under-
charged. If suction line temperature is lower
than table value, the system is overcharged.
Example: At outdoor air temperature of 84 F
and evaporator temperature of 40 F, the system
will be correctly charged at 66 F (x2 F) suction
line temperature.
8. Add charge by slowly opening Chargemaster
valve. If necessary, reduce charge by bleeding at
liquid line service valve. Check outdoor air and
evaporator temperature during procedure. If
they change, refer back to Suction Line Tem-
perature table for new value.
574
a
—>
Correct use of Chargemaster ensures an opti-
mum refrigerant charge will be in system when
conditions and system components are normal.
However, the Chargemaster does not solve or fix
system abnormalities. It indicates correct charge
for condition of system. It will not make correc-
tions for dirty filters, slow fans, excessively long or
short suction lines or other abnormal conditions.
This charging device ensures that a correct relation-
ship exists between outdoor temperature, evapora-
tor temperature, and suction line temperature on a
specific system.
Sight Glass Method — A satisfactory operating
charge can be obtained on 38GR TXV systems by
charging to a clear sight glass. For optimum charge,
use Charging Chart Method.
Elevate high-side pressure to 380 + 10 psig by
blocking condenser fan discharge or condenser
entering air. Charge to a clear sight glass while
holding high-side pressure constant.
Table 7 — Chargemaster Charging Chart
(Capillary Tube of AccuRater™ Systems)
EVAPORATOR T F
28 | 31 | 34 | 37: 43 | 45 | 48
Suction Line Temperatures
60 32] 40] 51 -
62 30 | 38 | 49
64 28 | 37 | 47 | 60
66 27 | 35 | 45 | 57
68 34 | 43 | 54
70 32 | 41 | 52
72 31 1 39 | 50
74 30 | 37 | 48
76 29 | 36 | 46
78 35 | 44
80 33 | 42 i
OUTDOOR
TEMP (F) L2U 25
88
90
92
94
96
98
*Saturated evaporator temperature which is the equivalent tem-
perature of pressure taken at the condensing unitsuction service
valve
STEN
PRESSURE AT LIQUID SERVICE VALVE (PSIG)
PRESSURE AT LIQUID SERVICE VALVE (PSIG)
50 60 70 80 90
PRESSURE AT SUCTION SERVICE VALVE (PSIG)
ig. 6 — 38GR002,003,004,045,005
Charging Chart — TXV Systems
o
Jor NR с
50 60 70 80 90
PRESSURE AT SUCTION SERVICE VALVE (PSIG)
ig. 7 — 38GR006 Charging Chart —
TXV Systems
COMPATIBLE FITTING REPAIR
Leaking Mechanical Connection — Frontseat con-
densing unit service valves and relieve refrigerant
pressure in tubing. Back locknut off compatible
fitting onto tube. Cut fitting between threads and
||
LA e
+
+
-, 00
Fig. 8 — Repair of Mechanical Connection
seal ring head as shown in Fig. 8. Remove tubing
section remaining in threaded portion of fitting.
Discard locknut.
Clean, flux, and insert new tube end into
remaining portion of compatible fitting. Wrap valve
base in wet rag. Heat and apply low-temperature
(450 F) solder.
Leaking Sweat Connection — Frontseat service
valves and relieve refrigerant pressure in tubing.
Clean and flux area around leak and apply low-
temperature (450 F) solder.
Evacuate or purge evaporator coil and tubing
system. Add refrigerant charge (see charging
instructions).
CONDENSER
Coil Cleaning — Clean by washing with refrigerant,
low-pressure water or steam.
Fan is correctly positioned in unit by placing fan
on motor shaft — align flat mark on top of fan hub
with flat on shaft. Press down evenly on top of fan
hub until shaft bottoms in fan hub.
Fan Motor Removal
. Shut off power to unit.
2. Remove unit top cover (grille). Open or remove
service door. With door open, remove control
anel cover.
—~ 3. Disconnect fan motor leads (4) from ‘control
anel located on service door. See Fig. 4.
4. Remove fan from motor shaft by pulling
upward on fan hub.
. Remove bolt holding fan motor to motor
mounting bracket. Remove motor with wiring
thru top of unit. To replace motor: place motor
on self-positioning motor mounting bracket and
retighten bolt.
When replacing metal fan with plastic fan,
remove slinger and spacer from fan motor shaft.
Wipe motor shaft clean — remove all rust
preventative.
Condenser Fan On
Condenser Air Restricted
Condenser Air Recirculating
Noncondensables in System
Refrigerant Overcharge
Improper Line Voltage
Refrigerant System Restriction
Loose Electric Connections
Faulty Run Capacitor
Condenser Fan Off
Fan Slipping on Shaft
Loose Electric Connections
Fan Motor Overload Open
Fan Motor Bearings Stuck
Fan Motor Defective
Low Suction Pressure
Low Refrig Charge
High Suction Pressure
Low Head Pressure
Defective Compressor Valves
Slightly Low Suction Pressure
Dirty Filters
Partially Restricted Air Flow
Coil Partially Iced
Slightly Low on Refrigerant
Duct Restricted
Dampers Partially Closed
373
LUBRICATION
Fan Motor Bearings are prelubricated.
Compressor contains factory oil charge. When oil is
lost, see Table 6 for oil recharge and Carrier
Standard Service Techniques Manual, Chapter 1,
page 1-21, for instructions. Use Carrier PP33-1,
Texaco Capella B or Suniso 3G oil.
TROUBLESHOOTING CHART
10
vaporafive Fan Running
Low Refrig Charge
Restricted Refrig Flow
Restricted Capillary
Defective TXV
Restricted Evaporator Air
Dirty or Iced Coil
Plugged Fiiter
Dampers Closed
Restricted Ductwork
Evaporator Fan Stopped
Defective Fan Relay
Loose Leads
Overload Open
Burned Out Motor
Broken Belt
Contactor Open
Dead Transformer
Thermostat Circuit Open
Faulty Control Relay
Overload Open
Contactor Coil Open
Loose Connection
Contactor Closed
Loose Leads at Compressor
Loose Leads at Contactor
Motor Windings Open
Internal Compr Overload Open
Contactor Closed Then Opens
Overload Opens
Compressor Stuck
Faulty CPCS Board
For replacement items use Carrier Specified Parts.
Manufacturer reserves the right to change any product specifications without notice.
CARRIER AIR CONDITIONING COMPANY
Tab 4 Form 38GR-35I Supersedes 38GR-1 SI Printed in U.S.A 574
* SYRACUSE,
12-72 Codes D and MS
NEW YORK
Catalog No. 533-869