Carrier 50ZHA024-060 Heat Pump User Manual

50ZHA024-060
Packaged Heat Pump Units
Visit www.carrier.com
Installation, Start-Up and Service Instructions
NOTE: Read the entire instruction manual before starting the
installation.
TABLE OF CONTENTS
SAFETY CONSIDERATIONS .....................................................1
INTRODUCTION ..........................................................................2
RECEIVING AND INSTALLATION ..........................................2
Check Equipment......................................................................2
IDENTIFY UNIT ................................................................2
INSPECT SHIPMENT ........................................................2
Provide Unit Support ................................................................2
SLAB MOUNT ...................................................................2
GROUND MOUNT ............................................................2
Provide Clearances....................................................................2
Place Unit..................................................................................2
Select and Install Ductwork .....................................................2
CONVERTING HORIZONTAL DISCHARGE
UNITS TO DOWNFLOW (VERTICAL) DISCHARGE ..................................................................4
Provide for Condensate Disposal .............................................4
Install Electrical Connections...................................................5
HIGH-VOLTAGE CONNECTIONS..................................5
ROUTING POWER LEADS INTO UNIT ........................6
CONNECTING GROUND LEAD TO UNIT GROUND .6
ROUTING CONTROL POWER WIRES ..........................6
ACCESSORY ELECTRIC HEAT WIRING .....................6
PRE-START-UP ............................................................................6
START-UP .....................................................................................7
Check for Refrigerant Leaks ....................................................8
LOCATE AND REPAIR REFRIGERANT LEAKS AND
CHARGE THE UNIT AS FOLLOWS: .............................8
Start-Up Cooling Section and Make Adjustments ..................8
CHECKING COOLING CONTROL OPERATION .........8
Refrigerant Charge....................................................................8
NO CHARGE ......................................................................8
LOW CHARGE COOLING ...............................................9
HEATING MODE CHARGE.............................................9
Indoor Airflow and Airflow Adjustments................................9
FOR 208/230-V .................................................................13
Unit Controls...........................................................................13
HIGH-PRESSURE RELIEF VALVE...............................13
LOSS OF CHARGE SWITCH.........................................13
COMPRESSOR OVERLOAD..........................................13
Sequence of Operation............................................................13
FAN OPERATION............................................................13
COOLING..........................................................................14
HEATING..........................................................................14
CONTINUOUS FAN ........................................................14
DEFROST..........................................................................14
ELECTRIC RESISTANCE HEATING............................14
MAINTENANCE.........................................................................15
Air Filter..................................................................................15
Unit Top Removal (Outdoor-Coil Side) ................................15
A05194
Fig. 1—Unit 50ZHA
Indoor Blower and Motor.......................................................15
Outdoor Coil, Indoor Coil, and Condensate Drain Pan ........16
Outdoor Fan ............................................................................16
Electrical Controls and Wiring...............................................16
Refrigerant Circuit ..................................................................17
Indoor Airflow ........................................................................17
Metering Devices ....................................................................17
Lubrication ..............................................................................17
Liquid Line Strainer................................................................17
High Flow Valves...................................................................17
TROUBLESHOOTING ...............................................................17
START-UP CHECKLIST............................................................17
NOTE TO INSTALLER—Before installation, READ THESE
INSTRUCTIONS CAREFULLY AND COMPLETELY. Also,
make sure the User’s Manual and Replacement Guide are left with
the unit after installation.
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can be
hazardous due to system pressure and electrical components. Only
trained and qualified workers should install, repair, or service
air-conditioning equipment.
Untrained workers can perform basic maintenance functions of
cleaning coils and filters. All other operations should be performed
by trained service people. When working on air-conditioning
equipment, pay attention to precautions in the literature, tags, and
labels attached to the unit, and other safety precautions that may
apply.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101
Printed in U.S.A.
Catalog No. 50ZHA-1SI
Pg 1
9-05
Replaces: New
Tab 6 8
A 6-in. wide gravel apron should be used around the flat surface to
prevent airflow blockage by grass or shrubs. Do not secure the unit
to the flat surface except where required by local codes.
Follow all safety codes. Wear safety glasses and work gloves. Use
quenching cloth for unbrazing operations. Have fire extinguisher
available for all brazing operations.
The unit should be level to within 1/4 inch. This is necessary for
the unit drain to function properly.
FIRE, EXPLOSION, ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
Before performing service or maintenance operations on
system, turn off main power to unit and install lockout tag.
Turn off accessory heater power switch if applicable.
GROUND MOUNT
The unit may also be installed directly on the ground if local codes
permit. Place unit on level ground prepared with gravel for
condensate discharge.
HURRICANE HOLD DOWN
Recognize safety information. This is the safety-alert symbol
.
When you see this symbol in instructions or manuals, be alert to
the potential for personal injury.
Contact you local distributor for specific hurricane hold down
details and PE (Professional Engineer) certification when required.
Understand the signal words DANGER, WARNING, CAUTION,
and NOTE. These words are used with the safety-alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies a hazard
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability,
or operation.
The required minimum service clearances and clearances to
combustibles are shown in Fig. 2. Adequate ventilation and
outdoor coil air must be provided.
Step 3—Provide Clearances
The outdoor fan pulls air through the outdoor coil and discharges
it through the fan on the top cover. Be sure that the fan discharge
does not recirculate to the outdoor coil. Do not locate the unit in
either a corner or under an overhead obstruction. The minimum
clearance under a partial overhang (such as a normal house
overhang) is 48 in. above the unit top. The maximum horizontal
extension of a partial overhang must not exceed 48 inches.
These instructions cover minimum requirements and conform to
existing national standards and safety codes. In some instances,
these instructions exceed certain local codes and ordinances,
especially those that may not have kept up with changing residential construction practices. We require these instructions as a
minimum for a safe installation.
Do not place the unit where water, ice, or snow from an overhang
or roof will damage or flood the unit. The unit may be installed on
wood flooring or on Class A, B, or C roof covering materials.
INTRODUCTION
50ZHA heat pump units are fully self-contained and designed for
outdoor installation (See Fig. 1). As shown in Fig. 2, units are
shipped in a horizontal-discharge configuration for installation on
a ground-level slab. All units can be field-converted to downflow
discharge configurations for rooftop applications with a fieldsupplied plenum.
OPERATIONAL HAZARD
Failure to follow this caution may result in unit component
damage.
Do not restrict outdoor coil airflow. An air restriction at either
the outdoor-air inlet or the fan discharge can be harmful to
compressor life.
RECEIVING AND INSTALLATION
Step 1—Check Equipment
Step 4—Place Unit
Unit can be moved with the rigging holds provided in the unit base.
Refer to Table 2 for operating weights. Use extreme caution to
prevent damage when moving the unit. Unit must remain in an
upright position during all moving operations. The unit must be
level with in 1/4” for proper condensate drainage; the ground-level
pad must be level before setting the unit in place. When a
field-fabricated support is used, be sure that the support is level
and that it properly supports the unit.
IDENTIFY UNIT
The unit model number and serial number are stamped on the unit
identification plate. Check this information against shipping papers. Verify that unit voltage and amperage listed on unit rating
plate agree with power supplied for equipment.
INSPECT SHIPMENT
Inspect for shipping damage while unit is still on shipping pallet.
If unit appears to be damaged or is torn loose from its securing
points, have it examined by transportation inspectors before
removal. Forward claim papers directly to transportation company.
Manufacturer is not responsible for any damage incurred in transit.
Step 5—Select and Install Ductwork
The design and installation of the duct system must be in
accordance with:
•
the standards of the NFPA (National Fire Protection Association) for installation of nonresidence-type air conditioning and
ventilating systems
To prevent loss or damage, leave all parts in original packages
until installation.
•
NFPA90A or residence-type, NFPA90B; and/or local codes
and residence-type, NFPA 90B
Step 2—Provide Unit Support
•
and/or local codes and ordinances
SLAB MOUNT
Select and size ductwork, supply-air registers and return-air grilles
according to ASHRAE (American Society of Heating, Refrigeration, and Air Conditioning Engineers) recommendations.
Check all items against shipping list. Immediately notify the
nearest Carrier Distributor if any item is missing.
Place the unit on a rigid, level surface, suitable to support the unit
weight. A concrete pad or a suitable fiberglass mounting pad is
recommended. The flat surface should extend approximately 2-in.
beyond the unit casing on the 2 sides. The duct connection side and
condensate drain connection sides should be flush with the edge of
the flat surface.
Use the duct flanges provided on the supply- and return-air
openings on the side of the unit. See Fig. 2 for connection sizes and
locations. The 14-in. round duct collars are shipped inside the unit
attached to the base pan in the indoor blower compartment. They
2
3
Fig. 2—Unit Base Dimensions, 50ZHA024-060
A05201
Table 1—Unit Specifications
UNIT
ELECTRICAL CHARACTERISTICS
50ZHA024
50ZHA030
50ZHA036
50ZHA042
50ZHA048
50ZHA060
208/230-1-60
208/230-1-60
208/230-1-60
208/230-1-60
208/230-1-60
208/230-1-60
UNIT WEIGHT
lb
293
324
377
389
384
433
kg
133
147
171
177
175
197
UNIT HEIGHT
IN. (MM)
″A″
30.13 (765)
34.13 (867)
42.13 (1070)
42.13 (1070)
42.13 (1070)
42.13 (1070)
CENTER OF GRAVITY IN. (MM)
14.0
14.0
14.0
14.0
14.0
14.0
X
(356)
(356)
(356)
(356)
(356)
(356)
19.0
19.0
19.0
19.0
19.0
19.0
Y
(483)
(483)
(438)
(483)
(483)
(483)
12.0
12.0
19.8
21.9
19.8
21.9
Z
(305)
(305)
(503)
(556)
(503)
(556)
Step 6—Provide for Condensate Disposal
are field-installed and must be removed from the indoor blower
compartment prior to start-up, even if they are not used for
installation.
NOTE: Be sure that condensate-water disposal methods comply
with local codes, restrictions, and practices.
When designing and installing ductwork, consider the following:
Unit removes condensate through a 1 3/64-in. ID hole (using
3/4-in. OD piping or tubing) which is located at the end of the unit.
See Fig. 2 for location of condensate connection.
UNIT DAMAGE HAZARD
Failure to follw this caution may result in damage to unit
components. When connecting ductwork to units, do not drill
deeper than 3/4 inch in shaded area shown in Fig. 3 or coil
may be damaged.
19.17
3.92
•
All units should have field-supplied filters installed in the
return-air side of the unit. Recommended sizes for filters are
shown in Table 2.
• Avoid abrupt duct size increases and reductions. Abrupt change
in duct size adversely affects air performance.
IMPORTANT: Use flexible connectors between ductwork and
unit to prevent transmission of vibration. Use suitable gaskets to
ensure weathertight and airtight seal. When electric heat is
installed, use fire proof canvas (or similar heat resistant material)
connector between ductwork and unit discharge connection. If
flexible duct is used, insert a sheet metal sleeve inside duct. Heat
resistant duct connector (or sheet metal sleeve) must extend 24–in.
from the unit discharge connection flange into the ductwork.
•
Size ductwork for cooling air quantity (cfm). The minimum air
quantity for proper electric heater operation is listed in Table 3.
Heater limit switches may trip at air quantities below those
recommended.
• Insulate and weatherproof all external ductwork. Insulate and
cover with a vapor barrier all ductwork passing through
conditioned spaces. Follow latest Sheet Metal and Air Conditioning Contractors National Association (SMACNA) and Air
Conditioning Contractors Association (ACCA) minimum installation standards for residential heating and air conditioning
systems.
• Secure all ducts to building structure. Flash, weatherproof, and
vibration-isolate duct openings in wall or roof according to
good construction practices.
Figure 4 shows a typical duct system with 50ZHA unit installed.
A05195
Fig. 3—Area Not to Be Drilled More Than 3/4-in.
Condensate water can be drained directly onto the roof in rooftop
installations (where permitted) or onto a gravel apron in groundlevel installations. Install a field-supplied condensate trap at end of
condensate connection to ensure proper drainage. Make sure that
the outlet of the trap is at least 1 in. lower than the drain-pan
condensate connection to prevent the pan from overflowing. Prime
the trap with water. When using a gravel apron, make sure it slopes
away from the unit.
CONVERTING HORIZONTAL DISCHARGE UNITS TO
DOWNFLOW (VERTICAL) DISCHARGE
If the installation requires draining the condensate water away
from the unit, install a 2-in. trap using a 3/4-in. OD tubing or pipe.
(See Fig. 5 and 6.) Make sure that the outlet of the trap is at least
1 in. lower than the unit drain-pan condensate connection to
prevent the pan from overflowing. Prime the trap with water.
Connect a drain tube using a minimum of 3/4-in. PVC, 3/4-in.
CPVC, or 3/4-in. copper pipe (all field supplied). Do not undersize
the tube. Pitch the drain tube downward at a slope of at least 1 in.
for every 10 ft of horizontal run. Be sure to check the drain tube
for leaks. Prime trap at the beginning of the cooling season
start-up. Allowable glues for condensate trap connection are:
Standard ABS, CPVC, or PVC cement.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before performing service or maintenance operations on
system, turn off main power to unit and install lockout tag.
Turn off accessory heater power switch if applicable.
Units are dedicated side supply products. They are not convertible
to vertical air supply. A field-supplied plenum must be used to
convert to vertical air discharge.
4
Table 2—Physical Data
UNIT 50ZHA
OPERATING WEIGHT (lbs)
COMPRESSOR TYPE
REFRIGERANT Charge (lb)
REFRIGERANT METERING DEVICE
Orifice ID (in.)
024
293
048
060
384
433
Ultra Tech Scroll
10.3
10.3
11.9
11.4
Accurater
CONDENSER COIL
Rows...Fins/in.
Face Area (sq. ft.)
2...21
11.1
CONDENSER FAN
Nominal Cfm
Diameter (in.)
Motor HP (RPM)
2600
20
1/8 (825)
3...17
4.3
800
10 x 8
1/2 (1050)
CONNECTING DUCT SIZES
Supply Air (in.)
Return Air (in.)
Return-Air Filters (in.)*
Throwaway
042
389
R-22
7.5
.067
.049
Evaporator Blower
Nominal Airflow (CFM)
Size (in.)
Motor HP (RPM)
036
377
Scroll
Orifice OD (in.)
EVAPORATOR COIL
Face Area (sq. ft.)
030
324
.082
.086
—
.059
.063
.070
Copper Tubes, Aluminum Plate Fins
2...21
2...21
2...21
2...21
12.7
15.8
15.8
13.3
Propeller
2600
3200
3200
3200
20
20
20
20
1/8 (825)
1/4 (1100)
1/4 (1100)
1/4 (1100)
Copper Tubes, Aluminum Plate Fins
3...17
4...17
4...17
4...17
4.9
4.9
6.1
4.9
Direct Drive
1000
1200
1400
1600
10 x 8
11 x 9
11 x 9
11 x 10
1/2 (1050)
3/4 (1050)
3/4 (1050)
1 (1050)
Round
14
14
24 x 24
.067
.057
24 x 24
24 x 24
13.3
TXV
24 x 30
30 x 30
—
.073
2...21
15.8
3300
20
1/2 (1100)
4...17
6.1
1875
11 x 10
1 (1050)
30 x 30
*Required filter sizes shown are based on the ARI (Air Conditioning and Refrigeration Institute) rated airflow at a velocity of 300 ft/min for throwaway type or 450 ft/min
for high capacity type. Recommended filters are 1-in. thick.
Step 7—Install Electrical Connections
UNIT DAMAGE HAZARD
Failure to follow these precautions may result in damage to
the unit being installed:
1. Make all electrical connections in accordance with NEC
ANSI/NFPA (latest edition) and local electrical codes
governing such wiring. In Canada, all electrical connections must be in accordance with CSA standard C22.1
Canadian Electrical Code Part 1 and applicable local
codes. Refer to unit wiring diagram.
2. Use only copper conductor for connections between
field-supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.
3. Be sure that high-voltage power to unit is within operating
voltage range indicated on unit rating plate.
4. Insulate low-voltage wires for highest voltage contained
within conduit when low-voltage control wires are run in
same conduit as high-voltage wires.
5. Do not damage internal components when drilling through
any panel to mount electrical hardware, conduit, etc.
Consult local power company for correction of improper
voltage.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
The 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 an electrical wire connected to the unit ground in
the control compartment, or conduit approved for electrical
ground when installed in accordance with NEC (National
Electrical Code), ANSI (American National Standards
Institute)/NFPA (latest edition) (in Canada, Canadian Electrical Code CSA C22.1) and local electrical codes.
HIGH-VOLTAGE CONNECTIONS
The unit must have a separate electrical service with a fieldsupplied, waterproof disconnect switch mounted at, or within sight
from the unit. Refer to the unit rating plate for maximum
fuse/circuit breaker size and minimum circuit amps (ampacity) for
wire sizing. See Table 6 for electrical data.
The field-supplied disconnect may be mounted on the unit over the
high-voltage inlet hole. (See Fig. 2.)
5
CONNECTING GROUND LEAD TO UNIT GROUND
INDOOR
THERMOSTAT
Refer to Fig. 8 and 9. Connect the ground lead to the chassis using
the unit ground in the control box.
ROUTING CONTROL POWER WIRES
RETURN
AIR
FROM
POWER
SOURCE
TOP COVER
POWER AND
LOW-VOLTAGE
ENTRY
Power Wiring
Control Wiring
Evaporator Airflow
Route thermostat wires through grommet providing a drip-loop at
the panel. Connect low-voltage leads to the thermostat as shown in
Fig. 10A & 10B.
DISCONNECT
PER NEC*
(UNIT AND
ELECTRIC
HEATER)
COMPOSITE
RUST-PROOF
BASEPAN
Condenser Airflow
Form a drip-loop with the thermostat leads before routing them
into the unit. Route the thermostat leads through grommeted hole
provided in unit into unit control box (See Fig. 7). Connect
thermostat leads and unit power leads as shown in Fig. 9, 10A &
10B.
The unit transformer supplies 24-v power for complete system
including accessory electrical heater. Transformer is factory wired
for 230-v operation.
CONDENSATE
DRAIN
CONNECTION
*Separate disconnect per NEC
(National Electrical Code) required
for electric heater when singlepoint conection is not used.
C00008
ACCESSORY ELECTRIC HEAT WIRING
C00008
Refer to accessory electric heat installation instructions for information on installing accessory electric heat. Accessory electric
heat wiring is shown in Fig. 11A, 11B, & 11C.
Fig. 4—Typical installation
1” (25mm) MIN.
TRAP
OUTLET
PRE-START-UP
2” (50mm) MIN.
FIRE, EXPLOSION, ELECTRICAL SHOCK HAZARD
Failure to observe the following warnings could result in
serious injury, death and/or property damage:
1. Follow recognized safety practices and wear protective
goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric power to
unit unless compressor terminal cover is in place and
secured.
3. Do not remove compressor terminal cover until all electrical sources are disconnected and lockout tag is installed.
4. Relieve all pressure from both high- and low-pressure sides
of the system before touching or disturbing anything inside
terminal box if refrigerant leak is suspected around compressor terminals. Use accepted methods to recover refrigerant.
5. Never attempt to repair soldered connection while refrigerant system is under pressure.
6. Do not use torch to remove any component. System
contains oil and refrigerant under pressure. To remove a
component, wear protective goggles and proceed as follows:
a. Shut off electrical power to unit and install lockout tag.
b. Relieve all refrigerant from system using both high- and
low-pressure ports. Use accepted methods to recover
refrigerant.
c. Cut component connecting tubing with tubing cutter and
remove component from unit.
d. Carefully unsweat remaining tubing stubs when necessary. Oil can ignite when exposed to torch flame.
C99013
Fig. 5—Condensate Trap (Using Tubing)
TRAP
OUTLET
1" min.
2" min.
C00009
Fig. 6—PVC Condensate Trap
Table 3—Minimum Airflow for Safe Electric Heater
Operation (CFM)
SIZE
Cfm
024
600
030
750
036
900
042
1050
048
1200
060
1500
UNIT DAMAGE HAZARD
Failure to follow this caution may result in unit component
damage. Operation of unit on improper line voltage constitutes abuse and may cause unit damage that could affect
warranty.
Use the Start-Up Checklist supplied at the end of this book and
proceed as follows to inspect and prepare the unit for initial
start-up:
ROUTING POWER LEADS INTO UNIT
1. Remove all access panels.
Use only copper wire between disconnect and unit. The highvoltage leads should be in a conduit until they enter the unit;
conduit termination at the unit must be watertight. Run the
high-voltage leads through the hole on the control box side of the
unit (see Fig. 7 for location). When the leads are inside the unit,
run leads to the control box (Fig. 8). For single-phase units,
connect leads to the black and yellow wires (see Fig. 9).
2. Read and follow instructions on all DANGER, WARNING,
CAUTION, and INFORMATION labels attached to, or
shipped with unit.
Make the following inspections:
a. Inspect for shipping and handling damages such as broken
lines, loose parts, disconnected wires, etc.
6
Table 4—Required Subcooling
Model Size
048
060
75 (24)
17.5 (9.7)
21 (11.7)
REQUIRED SUBCOOLING °F (°C)
Outdoor Ambient Temperature
82 (28)
85 (29)
17 (9.4)
16.5 (9.2)
20.5 (11.4)
20 (11.1)
95 (35)
16 8.9)
19 (10.6)
105 (41)
14 (7.8)
16 (8.9)
Table 5—Required Liquid Line Temperature
REQUIRED LIQUID LINE TEMPERATURE FOR A SPECIFIC SUBCOOLING (R-22)
Required Subcooling (°F)
Required Subcooling (°C)
Pressure (psig)
Pressure (kPa)
5
10
15
20
3
6
8
11
134
71
66
61
56
924
24
22
19
16
141
74
69
64
59
972
26
23
21
18
156
80
75
70
65
1075
30
27
24
21
163
83
78
73
68
1124
31
28
26
23
170
86
81
76
71
1172
33
30
27
24
177
89
84
79
74
1220
34
31
29
26
184
91
86
81
76
1268
36
33
30
27
191
94
89
84
79
1317
37
34
31
29
198
96
91
86
81
1365
38
36
33
30
205
98
93
88
83
1413
40
37
34
31
213
101
96
91
86
1468
41
38
36
33
221
104
99
94
89
1524
43
40
37
34
229
106
101
96
91
1579
44
41
38
36
237
108
103
98
93
1634
45
42
40
37
245
111
106
101
96
1689
47
44
41
38
253
113
108
103
98
1744
48
45
42
40
262
116
111
106
101
1806
49
46
44
41
271
118
113
108
103
1868
51
48
45
42
280
121
116
111
106
1930
52
49
46
44
289
123
118
113
108
1992
53
51
48
45
298
125
120
115
110
2054
55
52
49
46
307
128
123
118
113
2116
56
53
50
48
317
130
125
120
115
2185
57
54
52
49
327
132
127
122
117
2254
59
56
53
50
337
135
130
125
120
2323
60
57
54
52
347
137
132
127
122
2392
61
58
56
53
357
139
134
129
124
2461
62
60
57
54
367
142
137
132
127
2530
64
61
58
55
280
121
116
111
106
1930
52
49
46
44
289
123
118
113
108
1992
53
51
48
45
298
125
120
115
110
2054
55
52
49
46
307
128
123
118
113
2116
56
53
50
48
317
130
125
120
115
2185
57
54
52
49
327
132
127
122
117
2254
59
56
53
50
337
135
130
125
120
2323
60
57
54
52
347
137
132
127
122
2392
61
58
56
53
357
139
134
129
124
2461
62
60
57
54
367
142
137
132
127
2530
64
61
58
55
a. Make sure that outdoor-fan blade is correctly positioned in
fan orifice. Top edge of blade should be 3.125 in. down
from outdoor coil outlet grille (size 024–048, See Fig. 12)
or hub should be 0.708-in. away from motor end bell (size
060, See Fig. 13). See Outdoor Fan Adjustment section.
b. Inspect for oil at all refrigerant tubing connections and on
unit base. Detecting oil generally indicates a refrigerant
leak. Leak-test all refrigerant tubing connections using
electronic leak detector, or liquid-soap solution. If a refrigerant leak is detected, see following Check for Refrigerant
Leaks section.
b. Make sure that air filter is in place.
c. Inspect all field- and factory-wiring connections. Be sure
that connections are completed and tight. Ensure wires do
not contact refrigerant tubing or sheet metal edges.
c. Make sure that condensate drain trap is filled with water to
ensure proper drainage.
d. Make sure that all tools and miscellaneous loose parts have
been removed.
d. Inspect coil fins. If damaged during shipping and handling,
carefully straighten fins with a fin comb.
3. Verify the following conditions:
7
HIGH-VOLTAGE POWER
WIRING ENTRY HOLE
LOW-VOLTAGE WIRING
ENTRY HOLE
Step 2—Start-Up Cooling Section and Make Adjustments
UNIT DAMAGE HAZARD
Failure to follow this caution may result in unit component
damage.
Complete the required procedures given in the Pre-Start- Up
section this page before starting the unit. Do not jumper any
safety devices when operating the unit.
Do not operate the compressor in cooling mode when the
outdoor temperature is below 40 F.
Do not rapid-cycle the compressor. Allow 5 minutes between
‘‘on’’ cycles to prevent compressor damage.
CHECKING COOLING CONTROL OPERATION
Start and check the unit for proper cooling control operation as
follows:
1. Place room thermostat SYSTEM switch in OFF position.
Observe that blower motor starts when FAN switch is placed
in ON position and shuts down within 60 seconds (for
024-042) or 90 seconds (for 048 and 060) when FAN switch
is placed in AUTO position.
2. Place SYSTEM switch in COOL position and FAN switch in
AUTO position. Set cooling control below room temperature.
Observe that compressor, outdoor fan, and indoor blower
motors start and that reversing valve shifts. Observe that
cooling cycle shuts down when control setting is satisfied.
Reversing valve (RV) remains energized.
3. Place system switch in HEAT position. Observe that compressor, indoor fan and outdoor fan energize (Reversing Valve is
deenergized in heat pump heating mode). Set control above
room temperature. 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).
Step 3—Refrigerant Charge
Refrigerant Charge — Amount of refrigerant charge is listed on
unit nameplate and in Table 2. Refer to Carrier Refrigerant Service
Techniques Manual, Refrigerants section. Unit panels must be in
place when unit is operating during charging procedure. Unit must
operate a minimum of 15 minutes before checking charge.
NO CHARGE
Refer to Carrier Refrigerant Service Techniques. Use standard
evacuating techniques. After evacuating system, weigh in the
specified amount of refrigerant (refer to Table 2).
A05198
Fig. 7—Unit Electrical Connection
C00011
Fig. 8—Control Box Wiring
START-UP
Use the Start-Up Checklist supplied at the end of this book and
proceed as follows:
UNIT GROUND
Step 1—Check for Refrigerant Leaks
GROUND
LEAD
LOCATE AND REPAIR REFRIGERANT LEAKS AND
CHARGE THE UNIT AS FOLLOWS:
SINGLE-PHASE L
CONNECTIONS
3-PHASE
CONNECTIONS TO DISCONNECT L
TO DISCONNECT PER NEC
PER NEC
L
1. Using both high- and low-pressure ports, locate leaks and
reclaim remaining refrigerant to relieve system pressure.
2. Repair leak following accepted practices.
NOTE: Install a liquid-line filter drier whenever the system has
been opened for repair.
Fig. 9—Line Power Connections
8
BLK
YEL
BLU
C00012
3. Insulate the temperature sensing device so that the outdoor
ambient doesn’t affect the reading.
C
BROWN
4. Locate the measured suction line pressure in the top row of
Table 8 and the measured outdoor ambient temperature in the
left column of the table. Based on the two values, determine
the required suction line temperature.
RED
R
G
Y
O
5. If the measured suction line temperature is greater than the
tabulated temperature, add charge in the system.
GREEN
048 and 060 units:
1. Measure discharge line pressure by attaching a gauge to the
service port.
YELLOW
2. Measure the liquid line temperature by attaching a temperature
sensing device to it.
ORANGE
3. Insulate the temperature sensing device so that the outdoor
ambient doesn’t affect the reading.
WHITE
4. Refer to the required subcooling in Tables 4 and 5 to find the
required subcooling based on the model size and the outdoor
ambient temperature.
W2
VIOLET
5. Interpolate if the outdoor temperature lies in between the table
values. Extrapolate if the temperature lies beyond the table
range.
W3
Thermostat
and subbase
Unit Control
Power
6. Find the pressure value corresponding to the measured pressure on the compressor discharge line.
7. Read across from the pressure reading to obtain the Liquid line
temperature for a required subcooling.
A05207
Fig. 10A—Control Connections (Sizes 024-042)
8. Add charge if the measured temperature is higher than the
liquid line temperature value in the table.
9. Add charge using the service connection on the suction line of
the compressor.
BROWN
C
HEATING MODE CHARGE
Do not attempt to adjust charge by cooling methods while in heat
pump heating mode. Recover refrigerant and weigh in according to
unit data plate refrigerant data.
RED
R
Step 4—Indoor Airflow and Airflow Adjustments
GREEN
NOTE: For cooling operation, the recommended airflow is 350 to
450 cfm per each 12,000 Btuh of rated cooling capacity.
G
YELLOW
Table 7 shows dry coil air delivery for horizontal discharge units.
Tables 9-11 show pressure drops.
PINK
NOTE: Be sure that all supply- and return-air grilles are open,
free from obstructions, and adjusted properly.
Y
Y1
O
W2
ORANGE
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Disconnect electrical power to the unit and install lockout tag
before changing blower speed.
WHITE
VIOLET
W3
Thermostat
and subbase
Airflow can be changed by changing the 24 volts lead connections
of the blower motor.
Unit Control
Power
Unit 50ZHA blower motors are factory wired for rated airflow
operation.
A05208
FOR 208/230-V BLOWER MOTORS
Fig.10B—Control Connections (Sizes 048-060)
The motor lead speed connections are as follows:
LOW CHARGE COOLING
024-042 units:
1. Measure suction line pressure by attaching a gauge to the
service port.
2. Measure the suction line temperature by attaching a temperature sensing device to it.
SIZE
024
030
036
042
9
RATED AIRFLOW
Tap 1
Tap 2
Tap 1
Tap 2
HIGH AIRFLOW
Tap 3
Tap 4
Tap 3
Tap 4
A05199
Fig. 11A—Typical Unit Electrical Diagram (Sizes 024-042)
10
Fig. 11B—Typical Unit Electrical Diagram (Sizes 048-060)
11
A05200
A05209
Fig. 11C—Accessory Electric Heater Wiring
Table 6—Electrical Data—50ZHA
UNIT SIZE
50ZHA
V-PH-HZ
024
208/230–1–60
030
036
042
048
060
208/230–1–60
208/230–1–60
208/230–1–60
208/230–1–60
208/230–1–60
VOLTAGE
RANGE
COMPRESSOR
MIN
MAX
RLA
LRA
187
253
10.9
54.0
187
187
187
187
187
253
253
253
253
253
13.5
17.5
19.4
24.7
28.0
72.5
88.0
104.0
116.0
118.0
OFM
FLA
IFM
FLA
0.9
0.9
1.5
1.5
1.5
3.0
ELECTRIC HEAT
SINGLE POINT POWER SUPPLY
Nominal KW*
FLA
MCA
FUSE OR
CKT BKR
MOCP
4.1
—/—
3.8/5.0
7.5/10.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
26.0/30.0
18.6/18.6
41.2/44.7
63.8/70.7
51.1/56.1
25/25
45/50
—
50/50
—
—
60/70
—
4.1
—/—
3.8/5.0
7.5/10.0
11.3/15.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
54.2/62.5
26.0/30.0
21.8/21.8
44.4/47.9
57.0/73.9
89.5/100.0
54.3/59.3
30/30
50/50
—
—
60/60
—
—
70/70
90/100
—
6.0
—/—
3.8/5.0
7.5/10.0
11.3/15.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
54.2/62.5
26.0/30.0
29.4/29.4
52.0/55.4
74.5/81.5
97.1/107.5
61.9/66.9
35/35
60/60
—
—
—
—
—
80/80
100/100
70/70
6.0
—/—
3.8/5.0
7.5/10.0
11.3/15.0
15.0/20.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
54.2/62.5
72.2/83.3
26.0/30.0
31.7/31.7
54.3/57.8
76.9/83.8
99.4/109.9
122.0/135.9
63.2/69.2
40/40
—
—
—
—
—
—
60/70
80/90
100/110
110/150
70/80
7.7
—/—
3.8/5.0
7.5/10.0
11.3/15.0
15.0/20.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
54.2/62.5
72.2/83.3
26.0/30.0
40.0/40.0
62.6/66.1
85.1/92.1
107.7/118.1
130.3/144.2
72.5/77.5
50/50
—
—
—
—
—
—
80/80
100/100
110/125
125/125
90/90
7.7
—
3.8/5.0
7.5/10.0
11.3/15.0
15.0/20.0
5.4/7.2
—/—
18.1/20.8
36.1/41.7
54.2/62.5
72.2/83.3
26.0/30.0
45.7/45.7
68.2/71.7
90.8/97.8
113.4/123.8
135.9/149.9
78.2/83.2
60/60
—
—
—
—
—
—
90/90
100/110
125/125
125/150
90/100
FLA Full Load Amps
LRA Locked Rotor Amps
MCA Minimum Circuit Amps
MOCP Maximum Overcurrent Protection
RLA Rated Load Amps
NOTES:
1. In compliance with NEC (National Electrical Code) requirements for multimotor and combination load equipment (refer to NEC Articles 430 and 440), the overcurrent
protective device for the unit shall be Power Supply fuse. The CGA (Canadian Gas Association) units may be fuse or circuit breaker.
2. Minimum wire size is based on 60 C copper wire. If other than 60 C wire is used, or if length exceeds wire length in table, determine size from NEC.
12
Table 7—Dry Coil Air Delivery* Horizontal Discharge
(Deduct 10 percent for 208 Volt Operation)
50ZHA
SPEED TAP
WATTS/C.F.M
1
024
2
2
030
3
1
036
2
3
042
4
1
2
048
3
4
1
2
060
3
4
Watts
C.F.M.
Watts
C.F.M
Watts
C.F.M
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
Watts
C.F.M.
0.1
180
1344
269
1440
—
—
—
—
386
1680
—
—
224
1334
608
1931
737
2093
0.2
99
848
155
1108
166
1215
283
1404
204
1129
—
—
398
1652
440
1745
235
1288
626
1900
755
2061
.03
100
793
146
995
179
1172
305
1369
418
1572
209
1087
233
1164
409
1625
448
1717
251
1259
286
1333
643
1878
770
2028
EXTERNAL STATIC PRESSURE
0.4
0.5
0.6
0.7
118
130
142
757
698
632
222
233
970
918
157
170
951
884
261
275
1117
1053
191
204
216
1136
1095
1051
261
276
290
301
1343
1304
1272
1234
321
336
349
360
1333
1301
1273
1239
432
450
465
480
1543
1504
1475
1441
216
229
236
249
1027
994
932
881
245
254
266
276
1122
1066
1025
954
418
425
435
438
1583
1555
1515
1477
457
462
469
477
1684
1651
1612
1573
266
277
291
298
1224
1181
1157
1117
301
311
325
333
1296
1261
1232
1199
660
668
685
697
1844
1817
1789
1755
787
799
817
826
2001
1971
1934
1899
0.8
244
861
286
1014
316
1190
490
1418
—
—
289
906
441
1444
480
1537
344
1170
812
1850
0.9
257
795
291
980
329
1148
503
1380
—
—
—
—
451
1403
485
1508
370
1062
782
1757
1.0
260
729
315
877
342
1100
518
1332
—
—
—
—
—
—
486
1470
-
Air delivery values are based on operating voltage of 230-v., dry coil, without filter or electric heater. Deduct wet coil, filter, and electric heater pressure drops to obtain
external static pressure availabe for ducting.
Do not operate the unit at a cooling airflow that is less than 350 cfm for each 12,000 Btuh of rated cooling capacity. Evaporator coil frosting may occur at airflows below
this point.
Dashes indicate portions of the table that are beyond the blower motor capacity or are not recommended.
SIZE
048
060
RATED AIRFLOW
Low
High
Stage
Stage
Tap 1
Tap 3
Tap 1
Tap 3
This overload may require up to 60 minutes (or longer) to reset;
therefore, if the internal overload is suspected of being open,
disconnect the electrical power to the unit and check the circuit
through the overload with an ohmmeter or continuity tester.
HIGH AIRFLOW
Low
High
Stage
Stage
Tap 2
Tap 4
Tap 2
Tap 4
Step 6—Sequence of Operation
FAN OPERATION
Step 5—Unit Controls
The FAN switch on the thermostat controls indoor fan operation.
When the FAN switch is placed in the ON position, the IFR
(indoor-fan relay) is energized through the G terminal on the
thermostat. The normally-open contacts close, which then provide
power to the indoor (evaporator) fan motor (IFM). The IFM will
run continuously when the FAN switch is set to ON.
All compressors have the following internal-protection controls.
HIGH-PRESSURE RELIEF VALVE
This valve opens when the pressure differential between the low
and high side becomes excessive.
LOSS OF CHARGE SWITCH
COMPRESSOR OVERLOAD
When the FAN switch is set to AUTO, the thermostat deenergizes
the IFR (provided there is not a call for cooling). The contacts open
and the IFM is deenergized. The IFM will be energized only when
there is a call for cooling, in heat pump heating mode or if the unit
is equipped with accessory electric heat, the indoor-fan motor will
also run while the accessory electric heat is energized.
This overload interrupts power to the compressor when either the
current or internal temperature become excessive, and automatically resets when the internal temperature drops to a safe level.
NOTE: Some units are equipped with a time-delay relay. On
these units, the indoor fan remains on for 30 seconds after G or Y
is deenergized.
Located on the outdoor liquid line is a low-pressure switch which
functions as a loss-of-charge switch. This switch contains a
Schrader core depressor. This switch opens at 7 psig and closes at
22 psig. No adjustment is necessary.
13
Table 8—Cooling Charging Chart
OD Temp. (°F)
45
55
65
75
85
95
105
115
125
OD Temp. (°C)
7
13
18
24
29
35
41
46
52
52
51
—
—
—
—
—
—
—
—
361
11
—
—
—
—
—
—
—
—
54
55
—
—
—
—
—
—
—
—
370
13
—
—
—
—
—
—
—
—
56
60
53
—
—
—
—
—
—
—
SUCTION LINE TEMPERATURE (°F)
Suction Line Pressure (PSIG)
59
61
64
67
70
73
64
69
—
—
—
—
57
62
66
70
—
—
—
53
57
62
66
71
—
—
—
—
56
61
—
—
—
—
—
53
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
76
—
—
75
66
58
50
—
—
—
79
—
—
—
71
63
54
50
49
—
82
—
—
—
76
67
58
53
52
50
85
—
—
—
—
72
62
57
55
53
89
—
—
—
—
—
66
60
58
56
92
—
—
—
—
—
—
64
61
59
387
15
12
—
—
—
—
—
—
—
SUCTION LINE TEMPERATURE (°C)
Suction Line Pressure (kPa)
405
423
442
462
482
502
18
21
—
—
—
—
14
16
19
21
—
—
—
12
14
17
19
21
—
—
—
—
13
16
—
—
—
—
—
12
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
523
—
—
24
19
14
10
—
—
—
544
—
—
—
22
17
12
10
9
—
566
—
—
—
24
20
14
12
11
10
589
—
—
—
—
22
17
14
13
11
612
—
—
—
—
—
19
16
14
13
636
—
—
—
—
—
—
18
16
15
heating (Y2) energizes switching the compressor into high stage
heating through energizing an internal solenoid valve inside the
scroll compressor and switching the indoor fan into high stage. The
auxiliary or backup heat is controlled by a third stage (W2). If the
demand is not met, W3 is energized in case of staged heating.
When heating demand is satisfied, W3, W2 and Y2 sequentially
de-energize switching the compressor and the indoor fan into low
stage heating. When the low stage heating demand is met, Y1
de-energizes shutting the compressor, indoor fan and the outdoor
fan.
COOLING OPERATION (SIZES 024-042)
With a call for cooling (Y/Y2), the indoor fan energizes immediately whereas the contactor energizes after a 5 minute time delay
(in case of initial start-up) starting the compressor and the outdoor
fan motor. When the cooling demand is met, Y/Y2 de-energizes,
shutting the compressor, indoor fan and the outdoor fan.
COOLING OPERATION (SIZES 048 AND 060)
These units utilize a 2 stage indoor thermostat. With a first stage
call for cooling (Y1), the indoor fan (low stage) energizes
immediately whereas the contactor energizes after a 5 minute time
delay (in case of an initial start-up) starting the compressor (low
stage) and the outdoor fan motor. If the low stage operation cannot
satisfy the cooling demand, the second stage cooling (Y2) energizes switching the compressor into high stage cooling through
energizing an internal solenoid valve inside the scroll compressor
and switching the indoor fan into high stage. When second stage
cooling is satisfied, Y2 de-energizes switching the compressor and
the indoor fan into low stage cooling. When the low stage cooling
demand is met, Y1 de-energizes shutting the compressor, indoor
fan and the outdoor fan.
CONTINUOUS FAN
With the continuous Indoor fan option selected on the thermostat,
G is continuously energized. In case of 024-042 units, the selected
airflow setting is provided. In case of 048 and 060 units, the
system runs low stage (Y1) airflow for continuous fan operation.
DEFROST
Defrost board (DB) is a time and temperature control, which
includes a field-selectable time period between checks for defrost
(30, 60, 90 and 120 minutes). The time period is factory-set at 60
minutes and should only be adjusted by a trained service person.
Electronic timer and defrost cycle start only when contactor is
energized and defrost thermostat (DFT) is closed.
HEATING OPERATION (SIZES 024-042)
With a call for heating (Y1), the indoor fan (low stage) energizes
immediately whereas the contactor energizes after a 5 minute time
delay (in case of initial start-up) starting the compressor and the
outdoor fan motor. If Y/Y2 cannot satisfy the heating demand, the
auxiliary or backup heat (W2) energizes. In case of staged heating,
W3 is energized if the demand is not met. The highest airflow
selected is run while the electric heat is in operation. When heating
demand is met, W3, W2 and Y/Y2 sequentially de-energize
shutting the compressor, indoor fan and the outdoor fan.
Defrost mode is identical to Cooling mode. The outdoor fan motor
stops because of “OF1” and “OF2” contacts opening on the defrost
board, a bank of optional electric heat turns on to warm air
supplying the conditioned space.
ELECTRIC RESISTANCE HEATING
If accessory electric heaters are installed, on a call for “Emergency
Heat” the thermostat energizes W which energizes the heater relay
and in turn energizes the electric heaters. The IFR is energized
which starts the indoor-fan motor. If the heaters are staged, W2 is
energized when the second stage of heating is required. When the
need for heating is satisfied, the heater and IFM are de-energized.
HEATING OPERATION (SIZES 048 AND 060)
With a first stage call for heating (Y1), the indoor fan (low stage)
energizes immediately whereas the contactor energizes after a 5
minute time delay (in case of initial start-up) starting the compressor (low stage) and the outdoor fan motor. If the low stage
oepration cannot satisfy the heating demand, the second stage
MAINTENANCE
To ensure continuing high performance, and to reduce the possibility of premature equipment failure, periodic maintenance must
14
be performed on this equipment. This cooling unit should be
inspected at least once each year by a qualified service person. To
troubleshoot cooling of units, refer to Troubleshooting chart in
back of book.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Disconnect and tag electrical power to the unit before
removing top.
NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.
Only qualified service personnel should perform maintenance and
service procedures that require unit top removal.
FIRE, EXPLOSION, ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury,
death or property damage.
The ability to properly perform maintenance on this equipment requires certain expertise, mechanical skills, tools and
equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment, other than those
procedures recommended in the User’s Manual.
Refer to the following top removal procedures:
1. Remove screws on unit top cover surface. (Save all screws.)
2. Remove screws on unit top cover flange. (Save all screws.)
3. Lift top from unit carefully. Set top on edge and make sure
that top is supported by unit side that is opposite duct (or
plenum) side.
4. Carefully replace and secure unit top to unit, using screws
removed in Steps 1 and 2, when maintenance and/or service
procedures are completed.
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
Step 3—Indoor Blower and Motor
2. Inspect indoor coil, outdoor coil, drain pan, and condensate
drain each cooling and heating season for cleanliness. Clean
when necessary.
For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.
3. Inspect blower motor and wheel for cleanliness each cooling
and heating season. Clean when necessary. For first heating
season, inspect blower wheel bimonthly to determine proper
cleaning frequency.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Disconnect and tag electrical power to the unit before
cleaning the blower wheel.
4. Check electrical connections for tightness and controls for
proper operation each cooling season. Service when necessary.
5. Check the drain channel in the top cover periodically for
blockage (leaves, insects). Clean as needed.
To clean the blower wheel follow the following steps:
1. Remove the blower housing:
a. Remove the screws on the external side of the duct panel
that fasten the housing to the duct panel assembly.
FIRE, EXPLOSION, ELECTRICAL SHOCK, CUT HAZARD
Failure to follow these warnings could result in serious
personal injury, death, and/or property damage:
1. Turn off electrical power to the unit and install lockout tag
before performing any maintenance or service on the unit.
2. Use extreme caution when removing panels and parts. As
with any mechanical equipment, personal injury can result
from sharp edges, etc.
3. Never place anything combustible either on, or in contact
with, the unit.
b. Remove the side access panel and unscrew the mounting
bracket that fastens the blower housing to the internal
partition panel fo the control box assembly.
c. Make sure that the blower housing is supported by hand
before completely removing the mounting bracket.
d. Slide the blower housing from the rails of the duct panel
and place it outside the unit.
2. Remove the blower wheel from the housing:
a. Loosen the set screw which secures the wheel to the motor
shaft.
Step 1—Air Filter
NOTE: Never operate the unit without a suitable air filter in the
return-air duct system. Always replace the filter with the same size
as originally installed. See Table 2 for recommended filter sizes.
b. Loosen the three mounting legs of the motor by removing
the bolts that fasten themounting legs to the housing.
c. Slide out the motor assembly (motor, belly band and the 3
mounting legs) from the hub of the wheel.
Inspect air filter(s) at least once each month and replace
(throwaway-type) or clean (cleanable-type) at least twice during
each cooling season or whenever the filters become clogged with
dust and lint.
d. Remove the filler panel at the discharge end of the blower
housing by removing the two screws that fasten it to the
housing.
Replace filters with the same dimensional size and type as
originally provided, when necessary.
e. Remove the wheel form the housing.
3. Remove the caked on dirt from the wheel and the motor using
a brush.
Step 2—Unit Top Removal (Outdoor-Coil Side)
NOTE: When performing maintenance or service procedures that
require removal of the unit top, be sure to perform all of the routine
maintenance procedures that require top removal, including coil
inspection and cleaning, and condensate drain pan inspection and
cleaning.
4. Remove lint and dirt accumulations from the wheel and
housing with a vacuum cleaner, using a soft brush attachment.
5. Remove grease and oil with a mild solvent.
6. Reassemble
15
Table 9—Wet Coil Pressure Drop
UNIT SIZE
024
030
036
042
048
060
600
.027
-
700
.034
.036
-
800
040
.042
-
900
.047
.050
.050
-
STANDARD CFM (S.C.F.M.)
1100
1200
1300
1400
1500
.063
.072
.081
.063
.072
.081
.090
.097
.049
.052
.059
.065
.071
.072
.081
.090
.097
.071
1000
.053
.055
.055
.042
-
b. Install the filler panel.
d. Tighten the mounting bolts to fasten the motor assembly
with the housing.
e. Center the wheel in the housing by sliding it, align the flat
end of the shaft with the set screw and tighten the set screw.
f. Slide back the blower housing into the mounting rails in the
duct panel and install the mounting bracket back in its
position.
Step 4—Outdoor Coil, Indoor Coil, and Condensate
Drain Pan
Inspect the outdoor coil, indoor coil, and condensate drain pan at
least once heating and cooling season. Proper inspection and
cleaning requires the removal of the unit top. See Unit Top
Removal section.
1. Shut off unit power supply and install lockout tag.
2. Remove outdoor-fan assembly (grille, motor, motor cover,
and fan) by removing screws and flipping assembly onto unit
top cover.
Table 10—Filter Pressure Drop (in. wg)
3. Loosen fan hub setscrews.
CFM
800
900 1000 1100 1200 1300 1400
024-036 24 x 24 0.06 0.07 0.08 0.08 0.09 0.09
042-060 30 x 30
-
-
-
-
-
2000
.114
UNIT OPERATIONAL HAZARD
Failure to follow this caution may result in damage to unit
components.
Keep the Outdoor fan free from all obstructions to ensure
proper cooling operation. Never place articles on top of the
unit.
h. Replace the side access panel.
700
1900
.139
.098
Step 5—Outdoor Fan
g. Install the screws on the external side of the duct panel to
fasten duct panel with the housing.
600
1800
.091
.129
.091
Inspect the drain pan and condensate drain line when inspecting
the coils. Clean the drain pan and condensate drain by removing all
foreign matter from the pan. Flush the pan and drain tube with
clear water. Do not splash water on the insulation, motor, wiring,
or air filter(s). If the drain tube is restricted, clear it with a
‘‘plumbers snake’’ or similar probe device. Ensure that the
auxiliary drain port above the drain tube is also clear.
c. Reinsert the motor assembly in the wheel hub and align the
mounting legs with the housing mounting hold locations.
FILTER
SIZE
500
(IN.)
1700
.085
.120
.085
coil fins from inside to outside the unit. On units with an outer and
inner outdoor coil, be sure to clean between the coils. Be sure to
flush all dirt and debris from the unit base.
a. Slip the wheel back in the housing with the hub set screw
parented in the correct direction.
UNIT
SIZE
1600
.078
.108
.078
4. Adjust fan height as shown in Fig. 12 or 13.
0.09
0.10
0.11
0.12
5. Tighten setscrews.
-
-
0.08
0.09
6. Replace outdoor-fan assembly.
-
Step 6—Electrical Controls and Wiring
UNIT
SIZE
FILTER
CFM
SIZE
1500 1600 1700 1800 1900 2000 2100 2200 2300
(IN.)
024-036 24 x 24
0.14
0.15
-
-
-
-
-
-
-
042-060 30 x 30
0.10
0.11
0.12
0.13
0.14
0.15
0.16
0.17
0.18
Inspect and check the electrical controls and wiring annually. Be
sure to turn off the electrical power to the unit and install lockout
tag.
Remove the top panel to locate all the electrical controls and
wiring. Check all electrical connections for tightness. Tighten all
screw connections. If any smoky or burned connections are
noticed, disassemble the connection, clean all the parts, restrip the
wire end and reassemble the connection properly and securely.
Table 11—Accessory Electric Heat Pressure Drop
(in. wg)
CFM
HEATER KW
600 800 1000 1200 1400 1600 1800 2000 2200
5-20
0.06 0.08 0.10 0.13 0.15 0.18 0.20 0.23 0.25
Remove all obstructions (including weeds and shrubs) that interfere with the airflow through the outdoor coil. Straighten bent fins
with a fin comb. If coated with dirt or lint, clean the coils with a
vacuum cleaner, using a soft brush attachment. Be careful not to
bend the fins. If coated with oil or grease, clean the coils with a
mild detergent-and-water-solution. Rinse coils with clear water,
using a garden hose. Be careful not to splash water on motors,
insulation, wiring or air filter(s). For best results, spray outdoor-
3.125 in.
C00021
Fig. 12—Outdoor-Fan Adjustment (024–048 Size)
Check to ensure no wires are touching refrigerant tubing or sharp
sheet metal edges. Move and secure wires to isolate from tubing
and sheet metal edges.
16
and that the air filter is clean. When necessary, refer to Indoor
Airflow and Airflow Adjustments section to check the system
airflow.
Step 9—Metering Devices
Refrigerant cooling metering device is an Accurator (024-042) or
TXV (048 and 060) located upstream of the indoor coil distributor
assembly. Refrigerant heating mode metering device is an Accurater located upstrem of the outdoor coil distributor assembly.
0.708in.
Step 10—Lubrication
C02017
COMPRESSOR—The compressor is charged with the correct
amount of oil at the factory.
Fig. 13—Outdoor-Fan Adjustment (060 Size)
After inspecting the electrical controls and wiring, replace all the
panels. Start the unit, and observe at least one complete cooling
cycle to ensure proper operation. If discrepancies are observed in
operating cycle, or if a suspected malfunction has occurred, check
each electrical component with the proper electrical instrumentation. Refer to the unit wiring label when making these checkouts.
FAN MOTOR BEARINGS—Fan motor bearings are permanently lubricated. No further lubrication of outdoor or indoor fan
motors is required.
Step 11—Liquid Line Strainer
The liquid line strainer (to protect metering device) is made of wire
mesh and is located in the liquid line on the inlet side of the
metering device.
NOTE: Refer to the Sequence of Operation section, as an aid in
determining proper control operation.
Check valves are also located in the liquid lines near the strainers.
The Strainers are the larger of the two components.
Step 7—Refrigerant Circuit
Inspect all refrigerant tubing connections and the unit base for oil
accumulations annually. Detecting oil generally indicates a refrigerant leak.
Step 12—High Flow Valves
Located on the compressor hot gas and suction tubes are High
Flow Valves. Large black plastic caps distinguish these valves
with O-rings located inside the caps. These valves cannot be
accessed for service in the field. Ensure the plastic caps are in
place and tight or the possibility of refrigerant leakage could occur.
If oil is detected or if low cooling performance is suspected,
leak-test all refrigerant tubing using an electronic leak-detector, or
liquid-soap solution. If a refrigerant leak is detected, refer to Check
for Refrigerant Leaks section. (See Table of Contents for page
number.)
TROUBLESHOOTING
If no refrigerant leaks are found and low cooling performance is
suspected, refer to Refrigerant Charge. (See Table of Contents for
page number.)
Use the Troubleshooting Cooling and Heating guide if problems
occur with these units.
START-UP CHECKLIST
Step 8—Indoor Airflow
Use the Start-Up checklist to ensure proper start-up procedures are
followed.
The cooling airflow does not require checking unless improper
performance is suspected. If a problem exists, be sure that all
supply- and return-air grilles are open and free from obstructions,
17
OUTDOOR COIL
INDOOR COIL
ACCUMULATOR
B
A
STRAINER
COMPRESSOR
LCS
D
Check Valves
STRAINER
A
Open
B
Closed
C
Open
D
Closed
C
LEGEND
LCS
Loss of Charge Switch
Acutrol
Metering Device
Check Valve (Arrow indicates direction of flow)
HEATING CYCLE
1. Hot gas from compressor flows through the 4-way valve and is
directed to the cooling liquid line check valve. It is then condensed
and directed through subcooling circuits and out to the strainer
and the check valve in the heating liquid line.
2. The refrigerant then feeds the outdoor coil through the Acutrol
metering device on each circuit.
3. Each circuit evaporates the refrigerant and the circuits are combined in the outdoor header with some of the circuits flowing through
the check valve.
4. The refrigerant then flows through the 4-way valve, accumulator,
and back to the compressor.
C95045
Fig. 14—Typical Heat Pump Operation, Heating Mode
OUTDOOR COIL
INDOOR COIL
ACCUMULATOR
B
A
STRAINER
COMPRESSOR
LCS
D
Check Valves
STRAINER
A
Closed
B
Open
C
Closed
D
Open
C
LEGEND
LCS
Loss of Charge Switch
Acutrol
Metering Device
Check Valve (Arrow indicates direction of flow)
COOLING CYCLE
1. Hot gas from compressor flows through the 4-way valve and is
directed to the heating liquid line check valve. It is then condensed and subcooled through converging circuits. Refrigerant leaves
the outdoor coil by way of the strainer and the check valve in the
cooling liquid line.
2. The refrigerant then feeds the indoor coil through the Acutrol
metering device on each circuit.
3. Each circuit evaporates the refrigerant and the circuits are combined in the indoor coil header with some of the circuits flowing
through the check valve.
4. The refrigerant then flows through the 4-way valve, accumulator,
and back to the compressor.
C95044
Fig. 15—Typical Heat Pump Operation, Cooling Mode
18
Table 12—Troubleshooting—Cooling and Heating
SYMPTOM
Compressor and outdoor fan will not start.
Compressor will not start but outdoor fan
runs.
Compressor cycles
(other than normally satisfying thermostat).
Compressor operates continuously.
CAUSE
REMEDY
Power Failure
Call power company
Loss of Charge
Switch open
Evaluate unit for possible refrigerant leak
Fuse blown or circuit breaker tripped
Replace fuse or reset circuit breaker
Defective thermostat, contractor, transformer, or
control relay
Replace component
Insufficient line voltage
Determine cause and correct
Incorrect or faulty wiring
Check wiring diagram and rewire correctly
Thermostat setting too high
Lower thermostat setting below room temperature
Faulty wiring or loose connections in compressor
circuit
Check wiring and repair or replace
Compressor motor burned out, seized, or internal
overload open
Determine cause
Replace compressor
Defective run/start capacitor, overload, start relay
Determine cause and replace
Low input voltage
(20 percent low)
Determine cause and correct
Refrigerant overcharge or undercharge
Recover refrigerant, evacuate system, and recharge to capacities shown on nameplate
Loss of Charge
Switch open
Evaluate unit for possible refrigerant leak
Defective compressor
Replace and determine cause
Insufficient line voltage
Determine cause and correct
Blocked outdoor coil (cooling)
Determine cause and correct
Defective run/start capacitor, overload or start
relay
Determine cause and replace
Defective thermostat
Replace thermostat
Faulty outdoor-fan motor or capacitor
Replace
Restriction in refrigerant system
Locate restriction and remove
Dirty air filter
Replace filter
Unit undersized for load
Decrease load or increase unit size
Thermostat set too low
Reset thermostat
Low refrigerant charge
Locate leak, repair, and recharge
Leaking valves in compressor
Replace compressor
Frosted outdoor coil with incorrect
defrost operation (heating)
Check defrost time settings. Reset as necessary.
Check defrost temperature switch. Replace as necessary.
Air in refrigerant system
Recover refrigerant, evacuate system, and recharge
outdoor coil dirty or restricted
Clean coil or remove restriction
Dirty air filter
Replace filter
Dirty outdoor coil
Clean coil
Refrigerant overcharged
Recover excess refrigerant
Air in refrigerant system
Recover refrigerant, evacuate system, and recharge
Excessive head pressure.
Head pressure too low.
Excessive suction pressure.
Suction pressure too low.
Compressor runs but
outdoor fan does not.
Outdoor or indoor air restricted
or air is recirculating
Determine cause and correct
Low refrigerant charge
Check for leaks, repair and recharge
Compressor valves leaking
Replace compressor
Restriction in liquid tube
Remove restriction
High heat load
Check for source and eliminate
Compressor valves leaking
Replace compressor
Refrigerant overcharged
Recover excess refrigerant
Dirty air filter (cooling)
Replace Filter
Low refrigerant charge
Check for leaks, repair, and recharge
Metering device or low side restricted
Remove source of restriction
Insufficient indoor airflow (cooling)
Increase air quantity
Check filter- replace if necessary
Temperature too low in conditioned area (cooling)
Reset thermostat
Outdoor ambient below 40°F (cooling)
Install low-ambient kit
Field-installed filter-drier restricted
Replace
Normally closed contacts on
defrost board open
Check condition of relay on board.
Replace board if necessary.
19
START-UP CHECKLIST
(REMOVE AND STORE IN JOB FILE)
I. PRELIMINARY INFORMATION
Model No .............................................................................................................................................................
Serial No ..............................................................................................................................................................
Date ......................................................................................................................................................................
Technician ...........................................................................................................................................................
Customer Information(Name/Address) ...........................................................................................................................................................
II. PRE-START-UP
____ Verify that all packing materials have been removed from unit
____ Verify that condensate connection is installed per installation instructions
____ Check all electrical connections and terminals for tightness
____ Check wire proximity to refrigerant tubes and sheet metal edges
____ Check that indoor (indoor) air filter is clean and in place
____ Verify that unit installation is level
____ Check fan wheel propeller for location in housing and setscrew tightness
III. START-UP
Supply Voltage: L1-L2 __________ L2-L3 __________ L3-L1 __________
Compressor Amps: L1(C) __________ L2(S) __________ L3(R) __________
Indoor Fan Amps: __________ Outdoor Fan Amps: __________
TEMPERATURE-Cooling Mode
Outdoor Air Temperature: __________ DB ____________WB
Return-Air Temperature: __________ DB __________ WB
Cooling Supply Air: __________DB___________WB
PRESSURES-Cooling Mode
Refrigerant Suction __________ psig
Suction Line Temp* ___________
Refrigerant Discharge __________ psig
Discharge Temp†__________
TEMPERATURE-Heating Mode
Outdoor Air Temperature: __________ DB ____________WB
Return-Air Temperature: __________ DB __________ WB
Cooling Supply Air: __________DB___________WB
PRESSURES-Heating Mode
Refrigerant Suction __________ psig
Suction Line Temp* ___________
Refrigerant Discharge __________ psig
Discharge Temp†__________
____ Verify Refrigerant charge using charging tables
*Measured at suction inlet to compressor
†Measured at liquid line leaving outdoor coil
Copyright 2005 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
50zha1si
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101
Printed in U.S.A.
Catalog No. 50ZHA-1SI
Pg 20
9-05
Replaces: New
Tab 6 8