Bryant 575A Heat Pump User Manual

installation, start-up
and service instructions
COMMERCIAL AIR-COOLED
SPLIT SYSTEM HEAT PUMP
Cancels: II 575A-90-1
IMPORTANT — READ BEFORE INSTALLING
1. Read and become familiar with these installation instructions before installing this unit.
2. Be sure the installation conforms to all applicable local
and national codes.
3. These instructions contain important information for the
proper maintenance and repair of this equipment. Retain these instructions for future use.
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
I. Complete Pre-Installation Checks . . . . . . . . . . . . 1
II. Rig and Mount the Unit . . . . . . . . . . . . . . . . . . . . . 3
III. Complete Refrigerant Piping Connections . . . . . 4
IV. Make Electrical Connections . . . . . . . . . . . . . . . . 6
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
I. Preliminary Checks . . . . . . . . . . . . . . . . . . . . . . . . 8
II. Evacuate and Dehydrate . . . . . . . . . . . . . . . . . . . .8
III. Refrigerant and Oil Charge . . . . . . . . . . . . . . . . . . 8
IV. Refrigerant Service Ports . . . . . . . . . . . . . . . . . . . 9
V. Sequence of Operation . . . . . . . . . . . . . . . . . . . . . 9
VI. Checking Cooling and Heating Control
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
VII. Malfunction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11,12
I. Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
II. Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
III. Outdoor Fan Adjustment . . . . . . . . . . . . . . . . . . . 12
IV. Compressor Removal . . . . . . . . . . . . . . . . . . . . . 12
Size 090
71⁄2 Tons
II 575A-90-2
12/1/95
The 575A090 outdoor unit is approved for use only with the
524A-H090 indoor unit. Use only approved indoor unit.
The 575A090 unit is Underwriters’ Laboratories (UL) and UL
Canada approved for use with the 524A-H090 indoor unit only.
I. COMPLETE PREINSTALLATION CHECKS
A. Uncrate Unit (See Fig. 1)
Remove unit packaging except for the top skid assembly and
wood bumpers, which should be left in place until after unit
is rigged into place.
B. Inspect Shipment
File claim with shipping company if shipment is damaged or
incomplete.
C. Consider System Requirements
• Consult local building codes and NEC for special installation requirements.
• Allow sufficient space for airflow clearance, wiring, refrigerant piping, and servicing unit. See Fig. 2.
• Locate unit so that outdoor unit airflow is unrestricted on
all sides and above. Refer to Fig. 2.
• Unit may be mounted on a level pad directly on base rails
or mounted on raised pads at support points. See Fig. 2 for
weight distribution based on recommended support points.
• Provide for condensate drainage and defrost water disposal beneath unit.
• Areas with high snowfall may need elevated mounting for
adequate airflow.
NOTE: If vibration isolators are required for a particular installation, use corner weight information in Fig. 2 to make
proper selection.
TROUBLESHOOTING CHART . . . . . . . . . . . . . . . . . . . 13,14
START-UP CHECKLIST . . . . . . . . . . . . . . . . . . . . . CL-1,CL-2
SAFETY CONSIDERATIONS
Installing and servicing air-conditioning equipment can be hazardous due to system pressure and electrical components. Only
trained and qualified service personnel should install or service air-conditioning equipment.
When working on air-conditioning equipment, observe precautions in literature and on tags and labels attached to unit.
Follow all safety codes. Wear safety glasses and work gloves.
Use quenching cloth for brazing operations. Have fire extinguisher available. Read these instructions thoroughly. Consult local building codes and National Electrical Code (NEC)
for special installation requirements.
WARNING: Before installing or servicing system, always turn off main power to system. There may be more
than one disconnect switch. Electrical shock can cause
personal injury.
INSTALLATION
The 575A090 unit uses a semi-hermetic compressor. See
Table 1 for physical data.
575A
Fig. 1 — 575A090 Unit
UNIT
575A
090
UNIT W/
ALUMINUM-FIN
COIL
Dim. A Dim. B
18-89
18-59
[508.0] [431.8]
UNIT W/
WEIGHT (WITH ALUMINUM-FIN COIL)
COPPER-FIN
Std
Unit
Corner W Corner X Corner Y Corner Z
COIL
Dim. A Dim. B Lb Kg
Lb
Kg
Lb Kg Lb Kg Lb Kg
18-91⁄29 18-43⁄49 540 245 132
60
100
45 133 60 175 80
[546.0] [425]
WEIGHT (WITH COPPER-FIN COIL)
Std Unit
Corner X
Corner Y
Kg
Lb
Kg
Lb
Kg
Lb
Kg
Lb
Kg
608 276
160
73
117
53
142
64
189
86
Lb
Corner Z
ELECTRICAL CONNECTIONS
NOTES:
1. Dimensions in [ ] are in millimeters.
2.
Center of Gravity. See chart for dimensions.
3.
Corner W
AA
BB
CC
DD
Direction of airflow.
4. Minimum clearance (local codes or jurisdiction may prevail):
a. Bottom to combustible surfaces, 0 in. (0 mm)
b. Outdoor coil, for proper airflow, 36 in. (914 mm) one side, 12 in.
(305 mm) the other. The side getting the greater clearance is optional.
c. Overhead, 60 in. (1524 mm) to assure proper outdoor-fan operation.
d. Between units, control box side, 42 in. (1067 mm) per National
Electrical Code (NEC).
e. Between unit and ungrounded surfaces, control box side, 36 in.
(914 mm) per NEC.
f. Between unit and block or concrete walls and other grounded surfaces,
control box side, 42 in. (1067 mm) per NEC.
5. With the exception of the clearance for the outdoor coil as stated in
note 4b, a removable fence or barricade requires no clearance.
6. Units may be installed on combustible floors made from wood or Class A,
B, or C roof covering material.
7. Vertical center of gravity is approximately 40% of total unit height.
CONNECTION SIZES
13⁄89 Dia. [35] Field Power Supply Hole
29 Dia. [51] Power Supply Knockout
21⁄29 Dia. [64] Power Supply Knockout
7⁄89 Dia. [22] Field Control Wiring Hole
SERVICE VALVE CONNECTIONS
UNIT
575A090
Fig. 2 — Dimensions
—2—
SUCTION
11⁄89 [28.6]
LIQUID
⁄ 9 [12.7]
12
Table 1 — Physical Data
UNIT 575A
OPERATING WEIGHT (lb)
Aluminum Coils (Standard)
Copper Coils (Optional)
RIGGING WEIGHT (lb)
Aluminum Coils (Standard)
Copper Coils (Optional)
REFRIGERANT*
COMPRESSOR
Quantity...Type
Quantity Cylinders
Speed (rpm)
Oil Charge (oz) (ea)
OUTDOOR FAN
Quantity...rpm
Diameter (in.)
Motor Hp (NEMA)
Nominal Airflow (cfm)
OUTDOOR COIL
Face Area (sq ft)
Storage Capacity (lb)†
Fins/in.
Rows (No.)
CONNECTIONS (Sweat)
Suction (in.)
Liquid (in.)
CONTROLS
Pressurestat Settings (psig)
High Cutout
Cut-in
Low Cutout
Cut-in
Defrost Thermostat
Initiate Defrost (F)
Terminates Defrost (F)
B. Mounting
The unit must be elevated to ensure drainage from basepan
during sub-freezing conditions and to prevent or limit blockage of outdoor coil during snowfall. Consideration should be
given to specific geographical areas when determining height
of unit elevation.
090
540
608
590
658
R-22
Reciprocating, Semi-Hermetic
1...06DA818
4
1750
88
Propeller; Direct Drive
1...1100
26
3⁄4
6500
Enhanced Copper Tubes,
Aluminum Lanced Fins
18.0
16.56
17.0
2
C. Compressor Mounting
As shipped, compressors are held down by 4 bolts. After unit
is installed, loosen each bolt until the snubber washer can be
moved with finger pressure. See Fig. 4.
1 1 ⁄8
1 ⁄2
426
320
7
22
6
6
6
6
7
20
3
5
28
65
LEGEND
NEMA — National Electrical Manufacturing Association
*Unit is factory supplied with holding charge only.
†Storage capacity of coil with coil 80% full of liquid R-22 at 120 F.
UNIT
575A090
MAX WEIGHT
w/Al
w/Cu
Coil
Coil
Lb
Kg
Lb
Kg
590 268 658 298
A
in.
45.0
B
mm
1143
in.
38.5
C
mm
989
Al — Aluminum-Fin
Cu — Copper-Fin
II. RIG AND MOUNT THE UNIT
Fig. 3 — Rigging Label
CAUTION: Be sure unit panels are securely in place
prior to rigging.
A. Rigging
The unit is designed for overhead rigging. Refer to rigging
label for preferred rigging method. Spreader bars are not required if top crating is left on unit. All panels must be in place
when rigging. (See Fig. 3.) As further protection for coil faces,
plywood sheets may be placed against sides of unit, behind
cables. Run cables to a central suspension point so that angle
from the horizontal plane is not less than 45 degrees. Raise
and set unit down carefully.
If it is necessary to roll unit into position, mount unit on rails,
using a minimum of 3 rollers. Apply force to rails, not unit. If
unit is to be skidded into position, place it on a large pad and
drag it by the pad. Do not apply any force to unit.
Raise from above to lift unit from rails or pad when unit is in
final position.
After unit is in position, remove all shipping wrapping and
top crating.
—3—
Fig. 4 — Compressor Mounting
in.
43.5
mm
1105
NOTE: Unit is shipped with R-22 holding charge. System pressure must be relieved before removing caps. Recover refrigerant prior to brazing.
III. COMPLETE REFRIGERANT PIPING CONNECTIONS
Suction connection is sweat with plastic cap; liquid connection is sweat with plastic cap. Refer to Table 2 for the proper
line sizes. Follow standard piping practices.
Pass nitrogen or other inert gas through piping while brazing to prevent formation of copper oxide.
Table 2 — Refrigerant Piping Sizes
UNIT
575A
090
LINEAR LENGTH OF PIPING — ft
0-25
25-50
50-75
Line Size (in. OD)
L
S
L
S
L
S
1 ⁄2
5⁄8
5⁄8
1 1 ⁄8
11⁄8
13⁄8
C. Liquid Line Solenoid Valve
75-100
L
⁄
34
S
13⁄8
LEGEND
L — Liquid Line
OD — Outside Diameter
S — Suction Line
NOTES:
1. Pipe sizes are based on a 2° F loss for liquid and suction lines.
2. Pipe sizes are based on the maximum linear length shown for each
column, plus a 50% allowance for fittings.
3. Charge units with R-22 in accordance with unit installation
instructions.
A. Size Refrigerant Lines
Consider length of piping required between 575A unit and
524A-H unit, amount of liquid lift, and compressor oil return. See Table 3. Refer to 524A installation instructions for
additional information.
Table 3 — Liquid Line Data
UNIT
575A
090
MAX
ALLOWABLE
LIQUID LIFT (ft)
Heating
Cooling
75
65
LIQUID LINE
Max Allowable
Pressure Drop
(psi)
7
Max Allowable
Temp Loss
(F)
2
LEGEND
db — Dry Bulb
wb — Wet Bulb
NOTES:
1. The liquid lift in cooling mode is based on 80/67 F (db/wb ) entering
indoor-air temperature and a 95 F outdoor-air temperature, with R-22
refrigerant, at an indoor airflow of 3000 cfm.
2. The liquid lift in heating mode is based on 70/60 F (db/wb) entering
indoor-air temperature and a 47/43 F (db/wb) outdoor-air temperature, with R-22 refrigerant, at an indoor airflow of 3000 cfm.
B. Filter Drier and Moisture Indicator
See Fig. 5. The filter drier is factory supplied and fieldinstalled in the liquid line. Moisture indicator is fieldsupplied and should be installed just after liquid line shutoff
valve. Do not use a receiver; there is none provided with unit
and one should not be used.
—4—
A field-supplied liquid line solenoid valve (LLSV) is recommended when piping system length exceeds 75 feet. The LLSV
must be of the biflow type, suited for use in heat pump
systems.
NOTE: Part number EF23JS214 (Sporlan model CB14S2,
5⁄8-in. ODF/7⁄8-in. ODM) is recommended and is available from
the Replacement Components Division. This solenoid requires field-supplied Sporlan MKC-2 coils.
Wire the solenoid in parallel with the compressor contactor
coil.
Install the LLSV near the outdoor unit. The flow arrow must
be pointed toward the outdoor unit.
D. Safety Relief
A fusible plug is located on top of the accumulator. See Fig. 6.
Note that all safety relief components are factory installed.
Do not cap fusible plug. If local code requires additional
safety device(s), install as directed.
E. Suction Piping at Indoor Coil and TXV Sensing Bulb
Location
Suction piping must be designed so that refrigerant is thoroughly mixed after it leaves the indoor coil suction header.
The thermostatic expansion valve (TXV) sensing bulb must
also be correctly located. This ensures that the TXV sensing
bulb receives reliable readings. Install the suction piping as
follows:
1. Install a minimum of two 90-degree elbows upstream of
the TXV bulb location.
2. Locate the TXV bulb on a vertical riser where possible.
If a horizontal location is necessary, secure the bulb at
approximately the 4 o’clock position or the 8 o’clock position. See Fig. 7.
3. Make sure that the piping system has no inherent oil
traps, and that the piping layout does not allow oil to
migrate into an idle indoor coil.
4. Complete refrigerant piping from indoor coil to outdoor
coil before opening liquid and suction lines at the 575A
unit. See Tables 1 and 2 for piping selection data.
LEGEND
NEC — National Electrical Code
TXV — Thermostatic Expansion Valve
*Accessory item.
†Field supplied.
NOTES:
1. All piping must follow standard refrigerant piping techniques.
2. All wiring must comply with the applicable local and national codes.
3. Wiring and piping shown are general points-of-connection guides
only and are not intended for, or to include all details for, a specific installation.
4. Liquid line solenoid valve (solenoid drop control) is recommended to prevent refrigerant migration to the compressor. A biflow type solenoid valve is required.
5. Filter drier must be of the biflow type, suitable for heat pump duty.
6. Internal factory-supplied TXV and bypass check valve not shown.
Fig. 5 — Typical Piping Diagram, 575A/524A-H
—5—
A. Field Power Supply
All units except 208/230-v units are factory wired for the voltage shown on the nameplate. If the 208/230-v unit is to be
connected to a 208-v power supply, the transformer must be
rewired by disconnecting the black wire from the 230-v
orange wire on the transformer and connecting it to the 208-v
red wire from the transformer. The end of the orange wire
must then be insulated.
Refer to unit label diagram for additional information. Short
wire leads (pigtails) are provided for field wire connections.
Use factory-supplied splices or UL approved copper/aluminum
connector.
When installing units, provide a disconnect per NEC.
All field wiring must comply with NEC and local
requirements.
Install field wiring as follows:
1. Install conduit through side panel openings.
2. Install power lines to connections as shown in Fig. 8.
Wrap connections with electrical tape.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate (also see
Table 4). Voltages between phases must be balanced within
2% and the current within 10%. Use the formula shown in
Table 4, Note 2, to determine the percentage of voltage imbalance. Operation on improper line voltage or excessive phase
imbalance constitutes abuse and may cause damage to electrical components. Such operation invalidates any applicable
unit warranty.
B. Accessory Electric Heat
If the system is to be equipped with an accessory electric heater,
refer to the 524A-H090 installation instructions and Table 5.
Fig. 6 — Fusible Plug Locations
LEGEND
TXV — Thermostatic Expansion Valve
NOTE: The 8 o’clock position is shown above.
Fig. 7 — TXV Sensing Bulb Location
IV. MAKE ELECTRICAL CONNECTIONS
WARNING: Unit cabinet must have an uninterrupted,
unbroken electrical ground to minimize the possibility
of personal injury if an electrical fault should occur. This
ground may consist of electrical wire connected to unit
ground lug in control compartment, or conduit approved for electrical ground when installed in accordance with National Electrical Code (NEC) ANSI
(American National Standards Institute)/NFPA 70
(National Fire Protection Association) and local electrical codes. Failure to follow this warning could result in
the installer being liable for personal injury of others.
LEGEND
C
— Contactor
NEC — National Electrical Code
Field Wiring
Factory Wiring
Splice Connection
(Factory Supplied)
Fig. 8 — 575A090 Power Wiring Connections
—6—
Table 4 — Electrical Data
UNIT
575A
NOMINAL VOLTAGE
(V-Ph-Hz)
090
208/230-3-60
460-3-60
FLA
HACR
LRA
MCA
NEC
OFM
RLA
—
—
—
—
—
—
—
VOLTAGE RANGE
COMPRESSOR
OFM
Min
Max
RLA
LRA
FLA
187
414
254
508
31.5
15.7
160
80
3.1
1.4
LEGEND
Full Load Amps
Heating, Air Conditioning and Refrigeration
Locked Rotor Amps
Minimum Circuit Amps
National Electrical Code
Outdoor Fan Motor
Rated Load Amps
POWER SUPPLY
MAX FUSE OR
HACR BRKR AMPS
42.5
50
21.0
25
MINIMUM DISCONNECT
MCA
FLA
LRA
45
25
177
89
Example: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage =
452 + 464 + 455
3
=
1371
3
=
457
(AB) 457 2 452 = 5 v
(BC) 464 2 457 = 7 v
(AC) 457 2 455 = 2 v
Maximum deviation is 7 v.
Determine percent voltage imbalance
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equipment (refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuse or HACR breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply voltage is
greater than 2%. Use the following formula to determine the percent
voltage imbalance.
= 100 x
% Voltage Imbalance = 100
7
457
= 1.53%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
max voltage deviation from average voltage
average voltage
Table 5 — Accessory Electric Heater Data
UNIT
524A-H
NOMINAL kW
240-3-60
480-3-60
240-3-60
480-3-60
240-3-60
480-3-60
240-3-60
480-3-60
240-3-60
480-3-60
5
10
090
V-PH-HZ
15
25
35
HEATER
PART NO.
CAELHEAT001A00
CAELHEAT002A00
CAELHEAT004A00
CAELHEAT005A00
CAELHEAT007A00
CAELHEAT008A00
CAELHEAT010A00
CAELHEAT011A00
CAELHEAT013A00
CAELHEAT014A00
LEGEND
MCA — Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection (Amps)
*Sizes shown are for single-point connection of electric heat accessory
and air handler.
HEATER RATING
VOLTAGE
240
480
200
.694
—
208
.751
—
HEATER
AMPS
12.0
6.0
24.1
12.0
36.0
18.0
60.1
30.1
84.0
42.1
MCA*
MOCP*
25.6
12.3
40.7
19.8
55.7
27.4
85.8
42.4
115.8
57.4
30
15
50
25
80
40
125
60
175
80
NOTES:
1. MCA and MOCP values apply to both standard and alternate factorysupplied motors.
2. Electrical resistance heaters are rated at 240 v or 480 v. To determine heater capacity (kW) at unit nameplate voltage, multiply 240-v
or 480-v capacity by multipliers found in table below.
ACTUAL SITE VOLTAGE
230
240
400
440
.918
1
—
—
—
—
.694
.840
NOTE: The following equation converts kW of heat energy to Btuh:
kW x 3,412 = Btuh.
—7—
460
—
.918
480
—
1
C. Field Control Wiring
Install an approved accessory thermostat assembly according to installation instructions included with the accessory.
Locate thermostat assembly on a solid wall in the conditioned space to sense average temperature in accordance with
thermostat installation instructions.
Route thermostat cable or equivalent single leads of colored
wire from subbase terminals to low-voltage connections
on unit (shown in Fig. 9) as described in following Steps 1
through 3:
1. Pass the control wires through the hole provided in the
corner post. (See Fig. 10.)
2. Feed wire through the raceway built into the corner post
to the 24-v barriers located on the left side of the control box. The raceway provides the required clearance
between the high- and low-voltage wiring.
3. Connect thermostat wires to screw terminals of lowvoltage connection board.
NOTE: 39 VA is available for field-installed accessories. Control power requirement for heat pump outdoor unit is 36 VA
(sealed). The factory-supplied control transformer is rated at
75 VA.
NOTE: For wire runs, use the following insulated wire:
LENGTH
Ft
M
0-50
0-15.2
50-75
15.2-22.9
Over 75
Over 22.9
INSULATION
RATING (C)
35
35
35
AWG
18
16
14
SIZE
sq mm
0.82
1.30
2.08
LEGEND
AWG — American Wire Gage
All wire larger than no. 18 AWG (American Wire Gage) cannot be directly connected to the thermostat and will require
a junction box and splice at the thermostat.
CORNER
POST
RACEWAY
THERMOSTAT
FIELD CONNECTION
POWER WIRING
CONNECTIONS
Fig. 10 — Field Control Wiring Raceway
START-UP
I. PRELIMINARY CHECKS
1. Check that all internal wiring connections are tight and
that all barriers, covers, and panels are in place.
2. Field electrical power source must agree with unit nameplate rating.
3. Ensure all service valves are open. Ensure all compressor service valves are backseated.
4. Verify that compressor holddown bolts have been loosened and that flat/snubber washers can be rotated by
finger pressure (snug, but not tight).
5. Verify compressor crankcase heater is securely in place.
Crankcase heater must operate for at least 24 hours before start-up.
6. Note that compressor oil level is visible in the sight glass.
7. Check for leaks in refrigerant system by using soap bubbles
and/or electronic leak detector.
8. Check voltage imbalance as shown in Table 4, Note 2.
9. Check that both outdoor and indoor units are properly
mounted in accordance with installation instructions and
applicable codes.
II. EVACUATE AND DEHYDRATE
Evacuate and dehydrate entire refrigerant system using methods described in GTAC II, Module 4, System Dehydration.
III. REFRIGERANT AND OIL CHARGE
Refer to GTAC II, Module 5, Charging Recovery, Recycling,
and Reclamation.
NOTE: Use of a Totalclaimt refrigeration recovery unit is highly
recommended when recovering refrigerant.
Unit panels must be in place when unit is operating during
charging procedure.
Unit is shipped with holding charge only. Weigh in 15 lb of
R-22 to start unit.
A. Refrigerant Charging
Use Cooling Charging Chart (see Fig. 11). Vary refrigerant
until the conditions of the chart are met. Note that charging
chart is different from the type normally used. Chart is based
on charging the units to the correct subcooling for the various operating conditions. Accurate pressure gage and temperature sensing device are required. Connect the pressure
gage to the service port on the liquid line service valve. Mount
the temperature sensing device on the liquid line, close to the
liquid line service valve, and insulate it so that outdoor ambient temperature does not affect the reading. Indoor airflow
must be within the normal operating range of the unit.
Operate unit a minimum of 15 minutes. Ensure pressure and
temperature readings have stabilized. Plot liquid pressure and
temperature on chart and add or reduce charge to meet curve.
Adjust charge to conform with charging chart, using liquid
pressure and temperature to read chart.
LEGEND
C
H
HR
IFC
—
—
—
—
Cooling
Heating
Heater Relay
Indoor Fan Contactor
LLSV — Liquid Line Solenoid
Valve
SUPL — Supplemental
TB
— Terminal Block
Fig. 9 — Control Wiring Connections
—8—
When the thermostat is satisfied, contacts open, deenergizing C. The COMP, IFM, and OFM stop.
As shown in Fig. 12, cooling mode refrigerant flow is as
follows:
1. Hot refrigerant gas from compressor flows through the
reversing valve and is directed to the outdoor coil vapor
header.
2. Once at the outdoor coil vapor header, hot refrigerant
gas flows up to check valve ‘‘A,’’ which is closed. All refrigerant is then directed to complete a path through the
lower 6 coil circuits (6 passes in each circuit).
3. Refrigerant flows through from the liquid header side
outlets into the transfer header, where it flows upward.
4. Refrigerant leaves the transfer header through side connections in 4 locations and enters the middle coil circuits (4 coil circuits above check valve ‘‘A’’).
Fig. 11 — Cooling Charging Chart — 575A090
B. Oil Charging
Allow unit to run for about 20 minutes. Stop unit and check
compressor oil level. Add oil only if necessary to bring oil into
view in sight glass. See Table 1 for oil charge. Use only approved compressor oil as follows:
Suniso 3GS and WF32-150
Do not reuse drained oil or use any oil that has been exposed
to atmosphere. Procedures for adding or removing oil are given
in Refrigerant Service Techniques manual.
If oil is added, run unit for additional 10 minutes. Stop unit
and check oil level. If level is still low, add oil only after determining that piping system is designed for proper oil return and that system is not leaking oil.
IV. REFRIGERANT SERVICE PORTS
Each unit system has 3 service ports; one on the suction line,
one on the liquid line, and one on the compressor discharge
line. Be sure caps on the ports are tight.
V. SEQUENCE OF OPERATION
When power is supplied to unit, the transformer (TRAN) is
energized. The crankcase heater is also energized.
A. Cooling
With the thermostat in the cooling position, and when the
space temperature comes within 2° F of the cooling set point,
the thermostat makes circuit R-O. This energizes the reversing valve solenoid (RVS) and places the unit in standby condition for cooling.
As the space temperature continues to rise, the second stage
of the thermostat makes, closing circuit R-Y. When compressor time delay (5 ± 2 minutes) is completed, a circuit is made
to contactor (C ), starting the compressor (COMP) and outdoorfan motor (OFM). Circuit R-G is made at the same time, energizing the indoor-fan contactor (IFC) and starting the indoorfan motor (IFM) after one-second delay.
—9—
5. Refrigerant leaves the 4 middle coil circuits and enters
the top portion of vapor header. The refrigerant moves
up to the top 2 remaining coil circuits, where it enters
the subcooler section.
6. Subcooled refrigerant leaves the coil circuits through the
side outlets. It passes through check valve ‘‘B’’ into the
system liquid line and then into the indoor coil.
7. Liquid refrigerant is expanded and evaporated to a lowpressure vapor in the indoor coil. Refrigerant vapor then
returns to the outdoor unit through the system vapor
line, where it is drawn through the reversing valve
and accumulator and back to the compressor suction
connection.
B. Heating
On a call for heat, thermostat makes circuits R-Y and R-G.
When compressor time delay (5 ± 2 minutes) is completed, a
circuit is made to C, starting COMP and OFM. Circuit R-G
also energizes IFC and starts IFM after a 1-second delay.
If room temperature continues to fall, circuit R-W is made
through second-stage thermostat bulb. If optional electric heat
package is used, a relay is energized, bringing on supplemental electric heat. When thermostat is satisfied, contacts
open, deenergizing contactor and relay; motors and heaters
deenergize.
As shown in Fig. 13, heating mode refrigerant flow is as
follows:
1. Hot gas from compressor flows through the reversing valve
and is directed to the system vapor line and indoor coil
vapor header (not shown). Refrigerant is condensed and
subcooled in the indoor coil and returns to the outdoor
unit through the system liquid line.
2. Check valve ‘‘B’’ is closed and all liquid refrigerant enters the liquid header.
3. Refrigerant leaves the liquid header through 12 locations. It is then expanded in fixed orifice metering devices contained within the outlet tubes.
4. Refrigerant evaporates to low pressure vapor as it completes its passage through the 12 parallel coil circuits
(6 passes each).
5. Refrigerant moves from the coil circuits into the vapor
header, where it is drawn through the reversing valve
and accumulator and back to compressor suction
connection.
Fig. 12 — Cooling Mode Operation
C. Defrost
Defrost board (DB) is a time and temperature control, which
includes a field-selectable time period between checks for frost
(30, 50, and 90 minutes). Electronic timer and defrost cycle
start only when contactor is energized and defrost thermostat (DFT) is closed (below 28 F).
Defrost mode is identical to Cooling mode, except outdoorfan motor (OFM) stops and a bank of supplemental electric
heat turns on to warm air supplying the conditioned space.
Defrost mode is terminated when the DFT reaches 65 F.
VI. CHECKING COOLING AND HEATING CONTROL
OPERATION
Start and check the unit for proper control operation as
follows:
1. Place room thermostat SYSTEM switch in an OFF position. Observe that blower motor starts when FAN switch
is placed in ON position and shuts down when FAN switch
is placed in AUTO position.
2. Place SYSTEM switch in COOL position and FAN switch
in AUTO position. Set control below room temperature.
Observe that compressor, outdoor fan, and indoor fan
motors start. Observe that cooling cycle shuts down when
control setting is satisfied.
3. Place system switch in HEAT position. Set control above
room temperature. Observe that compressor, outdoor fan,
indoor-fan motor, and electric heaters (if equipped) start.
Observe that heating cycle shuts down when control setting is satisfied.
4. When using an automatic changeover room thermostat,
place both SYSTEM and FAN switches in AUTO positions. Observe that unit operates in Cooling mode when
temperature control is set to call for cooling (below room
temperature), and unit operates in Heating mode when
temperature control is set to call for heating (above room
temperature).
VII. MALFUNCTION
The high-pressure switch, loss-of-charge switch, and compressor overtemperature safety are located in a Cycle-LOC™ circuit that prevents heat pump operation if these safety devices
are activated.
The lockout system can be reset by adjusting the thermostat
to open the contacts (down for heating mode, up for cooling
mode) deenergizing the Cycle-LOC circuitry. Compressor overcurrent protection is achieved with overload breakers which
are temperature-sensitive and will automatically reset.
Unit is equipped with a no-dump reversing valve circuit. When
unit is in cooling mode, reversing valve remains in cooling
position until a call for heating is requested by thermostat.
When unit is in heating mode, reversing valve remains in heating position until there is a call for cooling.
—10—
Fig. 13 — Heating Mode Operation
SERVICE
CAUTION: When servicing unit, shut off all electrical power to unit to avoid shock hazard or injury from
rotating parts.
I. CLEANING
Inspect unit interior at the beginning of each cooling season
and as operating conditions require.
A. Outdoor Coil
Inspect coil monthly. Clean outdoor coil annually and as required by location or outdoor-air conditions.
Clean coil as follows:
1. Turn off unit power.
2. Remove and save top panel screws on outdoor unit.
3. Remove outdoor coil corner post. See Fig. 14. To hold
top panel open, place coil corner post between top panel
and side panel. See Fig. 15.
4. Remove bracket holding coil sections together at return
end of outdoor coil. Carefully separate the outer coil section 3 to 4 in. from the inner coil section. See Fig. 16.
5. Use a water hose or other suitable equipment to flush
down between the 2 coil sections to remove dirt and debris. Clean the outer surfaces with a stiff brush in the
normal manner.
6. Reposition the outer coil section and secure the sections
together. Remove the coil corner post from between the
top panel and side panel. Install the coil corner post and
replace all screws removed in Step 2.
—11—
Fig. 14 — Cleaning Outdoor Coil
Fig. 15 — Propping Up Top Panel
IV. COMPRESSOR REMOVAL
See Table 1 for compressor information. Follow safety codes
and wear safety glasses and work gloves.
1. Shut off power to unit. Remove unit access panel (front
of unit).
2. Remove refrigerant from system using refrigerant removal methods described in Refrigerant Service Techniques manual.
3. Disconnect compressor wiring at compressor terminal
box. Disconnect high-pressure switch.
4. Remove bolts from discharge service valve and suction
flange.
CAUTION: Excessive movement of copper lines at
compressor may cause higher levels of vibration when
unit is restored to service.
Fig. 16 — Separating Coil Sections
II. LUBRICATION
A. Compressors
Compressor has its own oil supply. Loss of oil due to a leak in
the system should be the only reason for adding oil after the
system has been in operation. See Start-Up, Oil Charging
section.
B. Fan Motor Bearings
Fan motor bearings are permanently lubricated. No further
lubrication is required.
5. Remove crankcase heater from compressor base.
6. Remove compressor holddown bolts and lift compressor off basepan.
7. Remove compressor from unit.
8. Clean system. Add new liquid line filter drier (biflow
type).
9. Install new compressor and position in unit. Connect
suction and discharge lines to compressor. Connect highpressure switch. Ensure that compressor holddown bolts
are in place. Connect wiring. Install crankcase heater.
10. Evacuate and recharge unit.
11. Restore unit power.
III. OUTDOOR FAN ADJUSTMENT (Fig. 17)
1. Shut off unit power supply.
2. Remove outdoor-fan assembly (grille, motor, motor cover,
and fan).
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig. 17.
5. Tighten setscrews.
6. Replace outdoor-fan assembly.
Fig. 17 — Outdoor-Fan Adjustment
—12—
—13—
TROUBLESHOOTING CHART, HEATING CYCLE
LEGEND
N.C. — Normally Closed
Copyright 1995 Carrier Corporation
CATALOG NO. BDP-3357-502
TROUBLESHOOTING CHART, COOLING CYCLE
LEGEND
TXV — Thermostatic Expansion Valve
START-UP CHECKLIST
I. PRELIMINARY INFORMATION
OUTDOOR:
MODEL NO.
SERIAL NO.
INDOOR:
MODEL NO.
SERIAL NO.
ADDITIONAL ACCESSORIES
B. Pre-Start-Up
OUTDOOR UNIT
(Y/N)
IS THERE ANY SHIPPING DAMAGE?
IF SO, WHERE:
WILL THIS DAMAGE PREVENT UNIT START-UP?
(Y/N)
CHECK POWER SUPPLY. DOES IT AGREE WITH UNIT?
HAS THE GROUND WIRE BEEN CONNECTED?
(Y/N)
(Y/N)
HAS THE CIRCUIT PROTECTION BEEN SIZED AND INSTALLED PROPERLY?
(Y/N)
ARE THE POWER WIRES TO THE UNIT SIZED AND INSTALLED PROPERLY?
(Y/N)
HAVE COMPRESSOR HOLDDOWN BOLTS BEEN LOOSENED (Snubber washers are snug, but not tight)?
(Y/N)
CONTROLS
ARE THERMOSTAT AND INDOOR-FAN CONTROL WIRING
CONNECTIONS MADE AND CHECKED?
(Y/N)
ARE ALL WIRING TERMINALS (including main power supply) TIGHT?
HAS CRANKCASE HEATER BEEN ENERGIZED FOR 24 HOURS?
(Y/N)
(Y/N)
INDOOR UNIT
HAS WATER BEEN PLACED IN DRAIN PAN TO CONFIRM PROPER DRAINAGE?
ARE PROPER AIR FILTERS IN PLACE?
(Y/N)
(Y/N)
HAVE FAN AND MOTOR PULLEYS BEEN CHECKED FOR PROPER ALIGNMENT?
DO THE FAN BELTS HAVE PROPER TENSION?
(Y/N)
(Y/N)
HAS CORRECT FAN ROTATION BEEN CONFIRMED?
(Y/N)
PIPING
IS LIQUID LINE SOLENOID VALVE LOCATED AT THE OUTDOOR UNIT AS RECOMMENDED?
(Y/N)
HAVE LEAK CHECKS BEEN MADE AT COMPRESSOR, OUTDOOR COIL, INDOOR COIL, TXV
(Thermostatic Expansion Valve), SOLENOID VALVES, FILTER DRIER, REVERSING VALVE, CHECK VALVE, AND
FUSIBLE PLUGS WITH A LEAK DETECTOR?
(Y/N)
LOCATE, REPAIR, AND REPORT ANY LEAKS.
HAVE ALL COMPRESSOR SERVICE VALVES BEEN FULLY OPENED (BACKSEATED)?
(Y/N)
HAVE LIQUID LINE SERVICE VALVE AND SUCTION LINE SERVICE VALVE BEEN OPENED?
(Y/N)
IS THE OIL LEVEL IN COMPRESSOR CRANKCASE INTO VIEW IN THE COMPRESSOR SIGHT GLASS?
(Y/N)
CHECK VOLTAGE IMBALANCE
LINE-TO-LINE VOLTS:
AB
V
AC
(AB + AC + BC)/3 = AVERAGE VOLTAGE =
V
BC
V
V
V
MAXIMUM DEVIATION FROM AVERAGE VOLTAGE =
VOLTAGE IMBALANCE = 100 X (MAX DEVIATION)/(AVERAGE VOLTAGE) =
IF OVER 2% VOLTAGE IMBALANCE, DO NOT ATTEMPT TO START SYSTEM!
CALL LOCAL POWER COMPANY FOR ASSISTANCE.
CL-1
%
CHECK OUTDOOR-FAN SPEED AND RECORD.
AFTER AT LEAST 15 MINUTES RUNNING TIME, RECORD THE FOLLOWING MEASUREMENTS:
COOLING
HEATING
OIL PRESSURE
SUCTION PRESSURE
SUCTION LINE TEMP
DISCHARGE PRESSURE
DISCHARGE LINE TEMP
ENTERING OUTDOOR-AIR TEMP
LEAVING OUTDOOR-AIR TEMP
INDOOR ENTERING-AIR DB (dry bulb) TEMP
INDOOR ENTERING-AIR WB (wet bulb) TEMP
INDOOR LEAVING-AIR DB TEMP
INDOOR LEAVING-AIR WB TEMP
COMPRESSOR AMPS (L1/L2/L3)
/
/
NOTES:
Copyright 1995 Carrier Corporation
CL-2
CATALOG NO. BDP-3357-502
CUT ALONG DOTTED LINE
CHECK INDOOR-FAN SPEED AND RECORD.
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C. Start-Up