38AUZ
Air-Cooled Condensing Units
60 Hz
with Puron® (R-410A) Refrigerant
Sizes 07, 08, 12, 14
Installation, Start-Up and
Service Instructions
CONTENTS
SAFETY CONSIDERATIONS
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION GUIDELINES. . . . . . . . . . . . . . . . . . . . . . . 2
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Step 1 — Plan for Unit Location . . . . . . . . . . . . . . . . . . 7
Step 2 — Complete Pre-Installation Checks. . . . . . . . . 7
Step 3 — Prepare Unit Mounting Support . . . . . . . . . 7
Step 4 — Rig and Mount the Unit . . . . . . . . . . . . . . . . . 7
Step 5 — Complete Refrigerant Piping Connections . 7
Step 6 — Install Accessories . . . . . . . . . . . . . . . . . . . . . 9
Step 7 – Complete Electrical Connections . . . . . . . . . . 9
PRE-START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Turn On Crankcase Heater . . . . . . . . . . . . . . . . . . . . . . 14
Preliminary Charge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
START-UP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 -18
38AUZ Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
OPERATING SEQUENCE. . . . . . . . . . . . . . . . . . . . . . . . . . 18
Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
ROUTINE SYSTEM MAINTENANCE. . . . . . . . . . . . . . . 18
Quarterly Inspection (and 30 days after initial start). 18
Seasonal Maintenance . . . . . . . . . . . . . . . . . . . . . . . . 18
SERVICE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 - 23
Comfort Alert Diagnostic Module. . . . . . . . . . . 19 - 21
Crankcase Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Compressor Protection. . . . . . . . . . . . . . . . . . . . . . . . . . 21
Low-Pressure Switches . . . . . . . . . . . . . . . . . . . . . . . . . 21
High-Pressure Switches. . . . . . . . . . . . . . . . . . . . . . . . . 21
Outdoor Fans. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
NOVATION™ Coil Cleaning and Maintenance . . . . 22
Repairing NOVATION Condenser Tube Leaks. . . . . 22
Replacing NOVATION Condenser Coil . . . . . . . . . . 22
Field Refrigerant Access Ports . . . . . . . . . . . . . . . . . 22
Factory High-Flow Access Ports. . . . . . . . . . . . . . . . 22
Fastener Torque Values . . . . . . . . . . . . . . . . . . . . . . . 23
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . 23, 24
APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Improper installation, adjustment, alteration, service,
maintenance, or use can cause explosion, fire, electrical shock
or other conditions which may cause personal injury or
property damage. Consult a qualified installer, service agency,
or your distributor or branch for information or assistance. The
qualified installer or agency must use factory-authorized kits or
accessories when modifying this product. Refer to the
individual instructions package
Follow all safety codes. Wear safety glasses and work gloves.
Use quenching cloths for brazing operations and have a fire
extinguisher available. Read these instructions thoroughly and
follow all warnings or cautions attached to the unit. Consult
local building codes and appropriate national electrical codes
(in USA, ANSI/NFPA70, National Electrical Code (NEC); in
Canada, CSA C22.1) for special requirements.
It is important to recognize safety information. This is the
safety-alert symbol
. When you see this symbol on the unit
and in instructions or manuals, be alert to the potential for
personal injury.
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 hazards 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.
Air Conditioner and Heat Pump with Puron® —
Quick Reference Guide . . . . . . . . . . . . . . . . . . . . . . . 25
START-UP CHECKLIST . . . . . . . . . . . . . . . . . . . CL-1, CL-2
Standard
Weight
Corner
A
Corner
B
Corner
C
Corner
D
Center of Gravity
Unit Height
UNIT
lbs.
kg.
lbs.
kg.
58
lbs.
kg.
31
lbs.
kg.
28
lbs.
kg.
32
X
Y
Z
H
21.00
[533.4]
19.00
[482.6]
13.00
[330.2]
42.36
[1076.0]
38AUZ*07
38AUZ*08
38AUZ*12
38AUZ*14
328 149 128
353 160 138
418 190 165
431 196 162
68
72
85
82
62
65
78
92
70
78
90
95
19.00
[482.6]
23.00
[584.2]
13.00
[330.2]
42.36
[1076.0]
63
75
73
33
39
37
29
35
42
35
41
43
23.00
[584.2]
20.00
[508.0]
15.00
[381.0]
50.36
[1279.2]
19.00
[482.6]
23.00
[584.2]
15.00
[381.0]
50.36
[1279.2]
Fig. 1 — 38AUZ*07-14 Unit Dimensions
3
Table 1A — Physical Data — 38AUZ*07-14 Units — 60 Hz English
UNIT SIZE 38AU
Z*07
Z*08
Z*12
Z*14
6
7.5
10
12.5
NOMINAL CAPACITY (tons)
OPERATING WEIGHT (lb)
Aluminum-Fin Coils (Standard)
328
353
418
431
R-410A
Scroll
REFRIGERANT TYPE*
Operating Charge, Typical (lb)†
Shipping Charge (lb)
8.4
4.4
10.2
4.9
13.8
6.3
18.0
7.3
COMPRESSOR
Qty...Model
Oil Charge (oz)
No. Cylinders
Speed (rpm)
1...ZP61
56
1...ZP83
60
1...ZP103
110
1...ZP137
110
N/A
3500
CONDENSER FANS
Qty...Rpm
Motor Hp
2...1100
1
/
4
Diameter
Nominal Airflow (Cfm Total)
Watts (Total)
22
6000
610
1...NOVATION
CONDENSER COIL (Qty)
Face Area (sq ft total)
Rows/Fins per inch (FPI)
Storage Capacity (lb)**
17.5
1/17
5.5
20.5
25.0
1/17
7.4
31.8
1/17
8.7
1/17
6.0
CONTROLS
Pressurestat Settings (psig)
High Cutout
Cut-in
630 ± 10
505 ± 20
54 ± 3
Low Cutout
Cut-in
117 ± 5
PIPING CONNECTIONS (in. ODS)
Qty...Suction
Qty...Liquid
1...11/8
1...3/8
1...11/8
1...1/2
1...13/8
1...1/2
1...13/8
1...5/8
LEGEND
ODS — Outside Diameter Sweat (socket)
* Unit is factory-supplied with partial charge only.
† Typical operating charge with 25 ft of interconnecting piping.
** Storage capacity of condenser coil with coil 80% full of liquid R-410A at 95°F.
4
Table 1B — Physical Data — 38AUZ*07-14 Units — 60 Hz SI
UNIT SIZE 38AU
Z*07
Z*08
Z*12
Z*14
21.1
26.4
35.1
44
NOMINAL CAPACITY (kW)
OPERATING WEIGHT (kg)
Aluminum-Fin Coils (Standard)
149
160
190
196
R-410A
Scroll
REFRIGERANT TYPE*
Operating Charge, Typical (kg)†
Shipping Charge (kg)
3.8
2.0
4.6
2.2
6.3
2.9
8.2
3.3
COMPRESSOR
Qty...Model
Oil Charge (L)
No. Cylinders
Speed (r/s)
1...ZP61
1.7
1...ZP83
1.8
1...ZP103
3.3
1...ZP137
3.3
N/A
58
CONDENSER FANS
Qty...r/s
Motor Hp NEMA
2...18
1
/
4
Diameter (mm)
Nominal Airflow (L/s)
Watts (Total)
560
2832
610
1...NOVATION
CONDENSER COIL (Qty)
Face Area (sq m total)
Rows/Fins per Meter (Fins/m)
Storage Capacity (kg)**
1.6
1...670
2.5
1.9
2.3
1...670
3.4
3.0
1...670
3.9
1...670
2.7
CONTROLS
Pressurestat Settings (kPa)
High Cutout
Cut-in
4347 ± 70
3482 ±138
372 ± 21
807 ± 34
Low Cutout
Cut-in
PIPING CONNECTIONS (in. ODS)
Qty...Suction
Qty...Liquid
1...11/8
1...3/8
1...11/8
1...1/2
1...13/8
1...1/2
1...13/8
1...5/8
LEGEND
NEMA — National Electrical Manufacturers Association
ODS — Outside Diameter Sweat (socket)
* Unit is factory-supplied with partial charge only.
† Typical operating charge with 7.62 m of interconnecting piping.
** Storage capacity of condenser coil with coil 80% full of liquid R-410A at 35°C.
5
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18
3
8 A U Z A 0 4 A 0
6
– 0 A 0 A 0
G
_____________
____
Model Type
Packaging
0 = Standard
1 = LTL
38AU= Carrier Condensing Unit
Puronr R---410A Refrigerant
Type of Coil
Z = Single Circuit, A/C Scroll Compressor
Electrical Options
A = None
C = Non-Fused Disconnect
Refrigerant Options
A = None
Service Options
B = Low Ambient
0 = None
1 = Un-powered Convenience Outlet
2 = Powered Convenience Outlet
Nominal Tonnage
07 = 6 Tons
08 = 7.5 Tons
12 = 10 Tons
14 = 12.5 Tons
Not Used
A = Place Holder
Base Unit Controls
Not Used
0 = Electro-Mechanical Controls
A = Not Used
Design Rev
--- = Catalog Model Number
Not Used
0 = Not Used
Voltage
1 = 575/3/60
5 = 208/230/3/60
6 = 460/3/60
Coil Options
G = Al/Al
Fig. 2 — Model Number Nomenclature
POSITION NUMBER
TYPICAL
1
4
2
8
3
0
4
8
5
G
6
1
7
2
8
3
9
4
10
5
POSITION
1−2
DESIGNATES
Week of manufacture (fiscal calendar)
3−4
Year of manufacture (”08” = 2008)
5
Manufacturing location (G = ETP, Texas, USA)
Sequential number
6−10
Fig. 3 — Serial Number Nomenclature
6
• Locate the unit so that the outdoor coil (condenser) air-
flow is unrestricted on all sides and above.
.INSTALLATION
• The unit may be mounted on a level pad directly on the
base channels or mounted on raised pads at support
points. See Tables 1A and 1B for unit operating weights.
See Fig. 1 for weight distribution based on recommended
support points.
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National
Electrical Code) ANSI/NFPA 70 for special installation
requirements.
2. Determine unit location (from project plans) or select unit
location.
NOTE: If vibration isolators are required for a particular
installation, use the data in Fig. 1 to make the proper
selection.
3. Check for possible overhead obstructions which may in-
terfere with unit lifting or rigging.
Step 3 — Prepare Unit Mounting Support
Slab Mount —
Provide a level concrete slab that extends a minimum of 6 in.
(150 mm) beyond unit cabinet. Install a gravel apron in front of
condenser coil air inlet to prevent grass and foliage from
obstructing airflow.
Step 1 — Plan for Unit Location
Select a location for the unit and its support system (pad, rails
or other) that provides for the minimum clearances required for
safety. This includes the clearance to combustible surfaces, unit
performance and service access below, around and above unit
as specified in unit drawings. See Fig. 4.
Step 4 — Rig and Mount the Unit
NOTE: Consider also the effect of adjacent units on airflow
performance and control box safety clearance.
Do not install the outdoor unit in an area where fresh air supply
to the outdoor coil may be restricted or when recirculation from
the condenser fan discharge is possible. Do not locate the unit
in a well or next to high walls.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
All panels must be in place when rigging. Unit is not
designed for handling by fork truck.
Evaluate the path and required line length for interconnecting
refrigeration piping, including suction riser requirements (out-
door unit above indoor unit), liquid line lift (outdoor unit below
indoor unit) and hot gas bypass line. Relocate sections to mini-
mize the length of interconnecting tubing.
.
RIGGING — These units are designed for overhead rigging.
Refer to the rigging label for preferred rigging method. Spread-
er bars are not required if top crating is left on the unit. All pan-
els must be in place when rigging. As further protection for coil
faces, plywood sheets may be placed against the sides of the
unit, behind cables. Run cables to a central suspension point so
that the angle from the horizontal is not less than 45 degrees.
Raise and set the unit down carefully.
DO NOT BURY REFRIGERATION LINES.
Although unit is weatherproof, avoid locations that permit
water from higher level runoff and overhangs to fall onto the
unit.
If it is necessary to roll the unit into position, mount the unit on
longitudinal rails, using a minimum of 3 rollers. Apply force to
the rails, not the unit. If the 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 the unit.
RIGHT:
Min 18” (457 mm)
REAR:
requried for service
Min 18” (457 mm)
requried for service
Raise from above to lift the unit from the rails or pad when unit
is in its final position.
After the unit is in position, remove all shipping materials and
top crating.
LEFT:
Min 18” (457 mm)
FRONT:
requried for service
42” (1067 mm)
Step 5 — Complete Refrigerant Piping
Connections
Note: Observe requirements for 39” (914 mm) operating clearance
on either Left or Rear coil opening.
IMPORTANT: Do not bury refrigerant piping underground.
Fig. 4 — Service Clearance Dimensional Drawing
Step 2 — Complete Pre-Installation Checks
IMPORTANT: A refrigerant receiver is not provided with
the unit. Do not install a receiver.
CHECK UNIT ELECTRICAL CHARACTERISTIC —
Confirm before installation of unit that voltage, amperage and
circuit protection requirements listed on unit data plate agree
with power supply provided.
UNCRATE UNIT — Remove unit packaging except for the
top skid assembly, which should be left in place until after the
unit is rigged into its final location.
PROVIDE SAFETY RELIEF — The 38AUZ unit is provided
with a fusible joint in the suction line in accordance with
applicable UL standards for pressure relief. If local codes
dictate an additional safety relief device, purchase locally and
install locally. Installation will require the recovery of the
factory shipping charge before the factory tubing can be cut
and the supplemental relief device is installed.
INSPECT SHIPMENT — File a claim with shipping compa-
ny if the shipment is damaged or incomplete.
SIZE REFRIGERANT LINES — Consider the linear length
of piping required between the outdoor unit and indoor unit
(evaporator), the amount of liquid lift (indoor section installed
above the outdoor section), and compressor oil return.
Consider and identify also the arrangement of the tubing path
(quantity and type of elbows in both lines), liquid line solenoid
size, filter drier and any other refrigeration specialties located
CONSIDER SYSTEM REQUIREMENTS
• Consult local building codes and National Electrical
Code (NEC, U.S.A.) for special installation requirements.
• Allow sufficient space for airflow clearance, wiring,
refrigerant piping, and servicing unit. See Fig. 1 for unit
dimensions and weight distribution data.
7
Table 3 — Refrigerant Piping Sizes —
38AUZ*07-14 60 Hz Units
in the liquid line. Refer to the indoor unit installation
instructions for additional details.
Determine equivalent line length adjustments for path and
components and add to linear line lengths. See Tables 2 and 3;
also refer to Part 3 of the Carrier System Design Manual and
E20-II® software for design details and line sizing.
LINEAR LENGTH OF INTERCONNECTING PIPING —
FT (m)
0-25
25-50
(7.5-15)
50-75
(15-23)
75-100
(23-30)*
UNIT
38AU
(0-7.5)
Line Size (in. OD)
Suction line sizing – Select a tube size that produces a suction
pressure drop in range of 1.5 to 3.0°F (0.8 to 1.7°C). (Higher
pressure drops are permissible but there will be a loss in
cooling capacity due to the higher pressure drop.) Insulate the
suction line.
Liquid line sizing – For linear line lengths up to 50-ft (15 m),
select a tube size that produces a liquid pressure drop of
approximately 2°F (1.1°C). For linear line lengths greater than
50-ft (15 m), select a line size that will permit the liquid
state-point subcooling entering the indoor coil’s TXV to be a
minimum of 2°F (1.1°C).
Hot Gas Bypass – Hot gas bypass, if used, should be
introduced before the evaporator. (A bypass route that also
bypasses the evaporator circuit may lead to oil trapping in the
evaporator circuit during low load conditions and then to oil
slugging as evaporator load increases.) Model 38AUZA units
do not include a hot gas stub connection; a tee must be field-
supplied and installed in the compressor discharge line. Run a
½-in OD line between outdoor unit and evaporator coil inlet.
Install an Auxiliary Side Connector at the evaporator between
TXV and distributor (follow instructions for the side connector
part). Insulate the hot gas line.
L
S
L
S
L
S
L
S
3
3
/
/
/
/
11/8
11/8
13/8
13/8
/
/
/
/
11/8
11/8
13/8
13/8
/
/
/
/
11/8
11/8
13/8
13/8
/
/
/
/
11/8
13/8
13/8
13/8
3
3
1
1
1
Z*07
Z*08
Z*12
Z*14
8
8
2
2
8
2
2
2
8
2
2
2
8
2
2
2
3
1
1
1
1
1
1
1
1
LEGEND
L — Liquid Line
S — Suction Line
*Field-supplied suction accumulator required for pipe length 75-100 ft
(23-30 m).
NOTES:
1. Pipe sizes are based on a 2°F (1°C) saturated temperature
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 unit with R-410A and verify that subcooled liquid exists
at TXV by checking for a full liquid line sight glass or by calcu-
lating subcooling at TXV.
INSTALL FILTER DRIER(S) AND MOISTURE
INDICATOR(S) — Every unit should have a filter drier and a
liquid-moisture indicator (sight glass). Refer to Table 4. In
some applications, depending on space and convenience re-
quirements, it may be desirable to install 2 filter driers and sight
glasses. One filter drier and sight glass may be installed at A
locations in Fig. 5; or, 2 filter driers and sight glasses may be
installed at B locations.
Select the filter drier for maximum unit capacity and minimum
pressure drop. Complete the refrigerant piping from the indoor
unit to the outdoor unit before opening the liquid and suction
lines at the outdoor unit.
Note that refrigerant suction piping should be insulated.
IMPORTANT: For 38AUZ*07-14 applications with liquid
5
lift greater than 20 ft (6 m), use / -in. liquid line.
8
Maximum lift is 60 ft (18 m).
Table 2 — Liquid Line Data —
38AUZ*07-14 60 Hz Units,
LIQUID LINE
INSTALL LIQUID LINE SOLENOID VALVE —
MAXIMUM
ALLOWABLE
LIQUID LIFT
ft (m)
Maximum
Allowable
Pressure
Drop
Maximum
Allowable
Temp.
SOLENOID DROP — It is recommended that a solenoid
valve be placed in the main liquid line (see Fig. 5) between the
condensing unit and the evaporator coil. Refer to Table 4. (A
liquid line solenoid valve is required when the liquid line
length exceeds 75 ft [23 m] or when the condensing unit is con-
nected to a chiller barrel in a built-up chiller system.) This
valve prevents refrigerant migration (which causes oil dilution)
to the compressor during the off cycle, at low outdoor ambient
temperatures. Wire the solenoid in parallel with the compressor
contactor coil (see Fig. 5). This means of electrical control is
referred to as solenoid drop control.
Loss
psig (kPa)
°F (°C)
60 (18)
7 (48)
2 (1)
*Inlet and outlet.
NOTE: Data shown is for units operating at 45°F (7.2°C) saturated
suction temperature and 95°F (35°C) entering air temperature. For
38AUZ*07-14 applications with liquid lift greater than 20 ft (6 m),
use 5/8-in. liquid line. Maximum lift is 60 ft (18 m).
INSTALL LIQUID LINE SOLENOID VALVE (Optional)
— CAPACITY CONTROL — If 2-step cooling is desired,
place a solenoid valve in the location shown in Fig. 5.
MAKE PIPING CONNECTIONS — Piping connections at
the 38AU unit are ball valves with stub tube extensions. Do not
open the unit service valves until all interconnecting tube braz-
ing as been completed.
The stub tube connections include ¼-in SAE service fittings
with Schrader valve cores (see Fig. 6). Before making any
brazed connections to the unit service valves, remove both
Schrader valve caps and cores and save for re-installation. Con-
nect a source for nitrogen to one of these service fittings during
tube brazing to prevent the formation of copper oxides inside
the tubes at brazed joints.
When connecting the field tubing to the 38AU service valves,
wrap the valves in wet rags to prevent overheating.
8
Table 4 — Refrigerant Specialities Part Numbers.
LIQUID LINE
SIZE (in.)
3
LIQUID LINE
LLSV
COIL
SIGHT
FILTER
DRIER
SUCTION LINE
UNIT
SOLENOID VALVE (LLSV)
GLASS
ACCUMULATOR
38AUZ*07
/
/
/
/
/
200RB5T3M
200RB5T3M
200RB5T4M
200RB6T4M
200RB6T5M
AMG/24V
AMG/24V
AMG/24V
AMG/24V
AMG/24V
AMI-1TT3
AMI-1TT3
AMI-1TT4
AMI-1TT4
AMI-1TT5
P502-8304S*
P502-8304S*
P502-8304S
P502-8307S*
P502-8307S*
S-7063S*
S-7063S*
S-7063S*
S-7063
8
8
2
2
8
3
1
1
5
38AUZ*08
38AUZ*12
38AUZ*14
S-7063
*Bushings required.
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal injury,
death and/or equipment damage.
Puron® (R-410A) refrigerant systems operate at higher
pressures than standard R-22 systems. Do not use R-22
service equipment or components on Puron refrigerant
equipment.
PRELIMINARY CHARGE — Before starting the unit, charge
R-410A liquid refrigerant into the high side of the system
through the liquid service valve. The amount of refrigerant
added must be at least 80% of the operating charge listed in the
Physical Data table (Tables 1A and 1B, pages 4 and 5) LESS
the factory charge quantity (if factory shipping charge has not
been removed). Allow high and low side pressures to equalize.
If pressures do not equalize readily, charge R-410A vapor
(using special service manifold with expansion device) into the
suction line service port for the low side of system to assure
charge in the evaporator. Refer to GTAC II, Module 5,
Charging, Recover, Recycling, and Reclamation for liquid
charging procedures.
LEGEND
TXV — Thermostatic Expansion Valve
Fig. 5 — Location of Sight Glass(es)
and Filter Driers
Step 6 — Install Accessories
Accessories requiring modifications to unit wiring should be
completed now. These accessories may include Winter Start
controls, Low Ambient controls, phase monitor, Compressor
LOCout. Refer to the instructions shipped with the accessory.
Field Service
Access Port
Factory
High-Flow
Access Port
(Schrader core)
Step 7 — Complete Electrical Connections
Service Valve
with Stem Cap
Sweat
Connection
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Fig. 6 — Typical Piping Connection Assembly
Pressure-test all joints from outdoor unit connections over to
the evaporator coil, using nitrogen as pressure and with soap-
and-bubbles.
When pressure-testing is completed, remove the nitrogen
source at the outdoor unit service valves and re-install the two
Schrader valve cores. Torque the cores to 2-3 in-lbs (23-34
N-cm).
EVACUATION/DEHYDRATION — Evacuate and dehydrate
the connected refrigeration system (excluding the 38AU unit)
to 500 microns using a two-stage vacuum pump attached to the
service ports outside the 38AU service valves, following de-
scription in GTAC II, Module 4, System Dehydration.
Do not use gas piping as an electrical ground. 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 NEC (National Electrical Code); ANSI/
NFPA 70, latest edition (in Canada, Canadian Electrical
Code CSA [Canadian Standards Association] C22.1), and
local electrical codes.
NOTE: Check all factory and field electrical connections
for tightness. Field-supplied wiring shall conform with the
limitations of 63°F (33°C) rise.
Field Power Supply —
If equipped with optional Powered Convenience Outlet: The
power source leads to the convenience outlet's transformer
primary are not factory connected. Installer must connect these
9
leads according to required operation of the convenience outlet.
If an always-energized convenience outlet operation is desired,
connect the source leads to the line side of the unit-mounted
disconnect. (Check with local codes to ensure this method is
acceptable in your area.) If a de-energize via unit disconnect
switch operation of the convenience outlet is desired, connect
the source leads to the load side of the unit disconnect. On a
unit without a unit-mounted disconnect, connect the source
leads to the factory connection leads (pigtails) in the unit’s
main control box (see Fig. 8).
All units -
All field wiring must comply with NEC and all local codes.
Size wire based on MCA (Minimum Circuit Amps) on the unit
informative plate. See Fig. 8 for power wiring connections to
the unit power terminal block and equipment ground.
Provide a ground-fault and short-circuit over-current protection
device (fuse or breaker) per NEC Article 440 (or local codes).
Refer to unit informative data plate for MOCP (Maximum
Over-current Protection) device size.
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 control transformer
must be rewired by moving the black wire with the ¼-in. female
spade connector from the 230-v connection and moving it to
the 208-v ¼-in. male terminal on the primary side of the
transformer. Refer to unit label diagram for to line-side
information. Field power wires will be connected line-side
pressure lugs on the power terminal block or at factory-
installed option non-fused disconnect.
Splice Terminals
(field supplied)
BLK
YEL
Field power wires are connected to the unit at the leads to the
factory connection leads (pigtails) in the unit’s main control
box (see Fig. 8) or at factory-installed option non-fused
disconnect switch. Max wire size is #4 AWG (copper only).
BLU
NOTE: TEST LEADS - Unit may be equipped with short
leads (pigtails) on the field line connection points on the
optional disconnect switch. These leads are for factory
run-test purposes only; remove and discard before connect-
ing field power wires to unit connection points.
DISCONNECT
Ground Lug
LEGEND
Factory Power Connection Lead
Field Power Supply Conductor
FIRE HAZARD
Failure to follow this warning could result in intermittent
operation or performance satisfaction.
Fig. 8 — Power Wiring Connections
Do not connect aluminum wire between disconnect switch
and condensing unit. Use only copper wire.
(See Fig. 7.)
All field wiring must comply with the NEC and local
requirements.
Affix the crankcase heater warning sticker to the unit
disconnect switch.
Convenience Outlets —
ELECTRIC
DISCONNECT
SWITCH
ELECTRICAL OPERATION HAZARD
COPPER
Failure to follow this warning could result in personal
injury or death.
WIRE ONLY
Units with convenience outlet circuits may use multiple
disconnects. Check convenience outlet for power status
before opening unit for service. Locate its disconnect
switch, if appropriate, and open it. Tag-out this switch, if
necessary.
ALUMINUM
WIRE
Fig. 7 — Disconnect Switch and Unit
Units Without Factory-Installed Disconnect —
Two types of convenience outlets are offered on 38AUZ
models: Non-powered and unit-powered. Both types provide a
125-volt GFCI (ground-fault circuit-interrupter) duplex
receptacle rated at 15-A behind a hinged waterproof access
cover, located on the end panel of the unit. See Fig. 9.
When installing units, provide a disconnect switch per NEC
(National Electrical Code) of adequate size. Disconnect sizing
data is provided on the unit informative plate. Locate on unit
cabinet or within sight of the unit per national or local codes.
Do not cover unit informative plate if mounting the disconnect
on the unit cabinet.
Units with Factory-Installed Disconnect —
The factory-installed option disconnect switch is located in a
weatherproof enclosure located under the main control box.
The manual switch handle is accessible through an opening in
the access panel.
10
Convenience
Outlet
GFCI
Pwd-CO
Fuse
Switch
Pwd-CO
Transformer
Control Box
Access Panel
UNIT
VOLTAGE
CONNECT
AS
PRIMARY
CONNECTIONS
TRANSFORMER
TERMINALS
Fig. 9 — Convenience Outlet Location
208,
230
L1: RED + YEL
L2: BLU + GRA
H1 + H3
H2 + H4
Non-powered type: This type requires the field installation of
a general-purpose 125-volt 15-A circuit powered from a source
elsewhere in the building. Observe national and local codes
when selecting wire size, fuse or breaker requirements and
disconnect switch size and location. Route 125-v power supply
conductors into the bottom of the utility box containing the
duplex receptacle.
240
L1: RED
Splice BLU +
YEL
H1
H2 + H3
H4
460
575
480
L2: GRA
L1: RED
L2: GRA
H1
H2
600
Unit-powered type: A unit-mounted transformer is factory-
installed to stepdown the main power supply voltage to the unit
to 115-v at the duplex receptacle. This option also includes a
manual switch with fuse, located in a utility box and mounted
on a bracket behind the convenience outlet; access is through
the unit's control box access panel. See Fig. 9.
The primary leads to the convenience outlet transformer are not
factory-connected. Selection of primary power source is a
customer-option. If local codes permit, the transformer primary
leads can be connected at the line-side terminals on the unit-
mounted non-fused disconnect or HACR breaker switch; this
will provide service power to the unit when the unit disconnect
switch or HACR switch is open. Other connection methods
will result in the convenience outlet circuit being de-energized
when the unit disconnect or HACR switch is open. See Fig. 10.
Duty Cycle: the unit-powered convenience outlet has a duty
cycle limitation. The transformer is intended to provide power
on an intermittent basis for service tools, lamps, etc; it is not
intended to provide 15-amps loading for continuous duty loads
(such as electric heaters for overnight use). Observe a 50%
limit on circuit loading above 8-amps (i.e., limit loads
exceeding 8-amps to 30 minutes of operation every hour).
Test the GFCI receptacle by pressing the TEST button on the
face of the receptacle to trip and open the receptacle. Check for
proper grounding wires and power line phasing if the GFCI
receptacle does not trip as required. Press the RESET button to
clear the tripped condition.
Fig. 10 - Powered Convenience Outlet Wiring
Fuse on power type: The factory fuse is a Bussman “Fusetron”
T-15, non-renewable screw-in (Edison base) type plug fuse.
Using unit-mounted convenience outlets: Units with unit-
mounded convenience outlet circuits will often require that two
disconnects be opened to de-energize all power to the unit.
Treat all units as electrically energized until the convenience
outlet power is also checked and de-energization is confirmed.
Observe National Electrical Code Article 210, Branch Circuits,
for use of convenience outlets.
Installing Weatherproof Cover –
A weatherproof while-in-use cover for the factory-installed
convenience outlets is now required by UL standards. This
cover cannot be factory-mounted due its depth; it must be
installed at unit installation. For shipment, the convenience
outlet is covered with a blank cover plate.
The weatherproof cover kit is shipped in the unit's control box.
The kit includes the hinged cover, a backing plate and gasket.
DISCONNECT ALL POWER TO UNIT AND
CONVENIENCE OUTLET.
Remove the blank cover plate at the convenience outlet;
discard the blank cover.
Loosen the two screws at the GFCI duplex outlet, until
approximately 1/2-in (13 mm) under screw heads are exposed.
Press the gasket over the screw heads. Slip the backing plate
over the screw heads at the keyhole slots and align with the
gasket; tighten the two screws until snug (do not over-tighten).
Mount the weatherproof cover to the backing plate as shown in
Fig. 11. Remove two slot fillers in the bottom of the cover to
permit service tool cords to exit the cover. Check for full
closing and latching.
11
COVER – WHILE-IN-USE
WEATHERPROOF
RECEPTACLE
NOT INCLUDED
Central
Terminal
Board
R
G
X
C
X
Y1
C
G
G
O/B/Y2
(Notes 1, 2)
W2
W2
W1
Y2
Y1
R
W1
Y2
Y1
R
C
(Note 3)
T–STAT
BASE PLATE FOR
GFCI RECEPTACLE
Note 1: Typical multi-function marking. Follow manufacturer’s configuration
instructions to select Y2.
Note 2: Y2 to economizer required on single-stage cooling units when
integrated economizer function is desired
Note 3: Connect only if thermostat requires 24-vac power source.
Field Wiring
Fig. 11 — Weatherproof Cover Installation
All Units —
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. See Table 5.
On 3-phase units, voltages between phases must be balanced
within 2% and the current within 10%. Use the formula shown
in the legend for Table 5, Note 5 (see page 13) to determine the
percent of voltage imbalance. Operation on improper line
voltage or excessive phase imbalance constitutes abuse and
may cause damage to electrical components. Such operation
would invalidate any applicable Carrier warranty.
Field Control Wiring — Unit control voltage is 24 v. See
Fig. 8 and the unit’s label diagram for field-supplied wiring
details. Route control wires through the opening in unit’s end
panel to the connections terminal board in the unit’s control
box.
Fig. 12 — Typical Remote Thermostat Connections
CONTROL CIRCUIT WIRING — Control voltage is 24 v.
See Fig. 8 and the unit’s label diagram for field-supplied
wiring details. Route control wires through the opening in
unit’s end panel to the connection in the unit’s control box.
CONTROL TRANSFORMER WIRING (38AUZ07-14
Units) — On multivoltage units, check the transformer
primary wiring connections. See Fig. 13 or refer to the unit’s
label diagram.
If the unit will be operating at 208-3-60 power, remove the
black wire (BLK) from the transformer primary connection
labelled “230” and move it to the connection labelled “208”.
See Fig. 13.
The 38AUZ unit requires an external temperature control
device. This device can be a thermostat (field-supplied) or a
PremierLink controller (available as factory-installed option or
as field-installed accessory, for use on a Carrier Comfort
Network or as a stand alone control).
Thermostat —
Install a Carrier-approved accessory thermostat according to
installation instructions included with the accessory. For
complete economizer function, select a two—stage cooling
thermostat. Locate the thermostat accessory on a solid wall in
the conditioned space to sense average temperature in
accordance with the thermostat installation instructions.
If the thermostat contains a logic circuit requiring 24-v power,
use a thermostat cable or equivalent single leads of different
colors with minimum of four leads. If the thermostat does not
require a 24-v source (no “C” connection required), use a
thermostat cable or equivalent with minimum of three leads.
Check the thermostat installation instructions for additional
features which might require additional conductors in the
cable.
Fig. 13 — Control Transformer Wiring
For wire runs up to 50 ft. (15 m), use no. 18 AWG (American
Wire Gage) insulated wire (35°C minimum). For 50 to 75 ft.
(15 to 23 m), use no. 16 AWG insulated wire (35°C minimum).
For over 75 ft. (23 m), use no. 14 AWG insulated wire (35°C
minimum). All wire sizes larger than no. 18 AWG cannot be
directly connected to the thermostat and will require a junction
box and splice at the thermostat.
PremierLink (accessory installation) – Refer to Form 33CS-
58SI for details on connecting the PremierLink controller and
its various sensors.
12
Table 5 — Electrical Data — 38AUZ*07-14 60 Hz Units
NOMINAL
VOLTAGE
VOLTAGE
RANGE*
FAN MOTORS
(Qty 2)
POWER
SUPPLY
UNIT
SIZE
38AU
FACTORY-
INSTALLED
OPTION
COMPRESSOR
V-Ph-Hz
MIN
MAX
RLA
LRA
FLA (ea)
LRA (ea)
MCA
MOCP
NONE OR DISCONNECT
CONVENIENCE OUTLET
208/230-3-60
187
414
518
187
414
518
187
414
518
187
414
518
253
506
633
253
506
633
253
506
633
253
506
633
19
123
1.5
0.8
0.6
1.5
0.8
0.6
1.5
0.8
0.6
1.5
0.8
0.6
3.7
25.2
12.9
9.9
45
NONE OR DISCONNECT
CONVENIENCE OUTLET
460-3-60
575-3-60
9.7
7.4
62
50
1.9
1.6
3.7
1.9
1.6
3.7
1.9
1.6
3.7
1.9
1.6
20
15
50
25
20
60
30
25
80
30
30
Z*07
Z*08
NONE OR DISCONNECT
CONVENIENCE OUTLET
NONE OR DISCONNECT
CONVENIENCE OUTLET
208/230-3-60
460-3-60
25
164
100
78
32.7
16.0
11.8
39.1
21.7
15.8
61.6
24.0
19.0
NONE OR DISCONNECT
CONVENIENCE OUTLET
12.2
9.0
NONE OR DISCONNECT
CONVENIENCE OUTLET
575-3-60
NONE OR DISCONNECT
CONVENIENCE OUTLET
208/230-3-60
460-3-60
30.1
16.7
12.2
48.1
18.6
14.7
225
114
80
NONE OR DISCONNECT
CONVENIENCE OUTLET
Z*12
Z*14
NONE OR DISCONNECT
CONVENIENCE OUTLET
575-3-60
NONE OR DISCONNECT
CONVENIENCE OUTLET
208/230-3-60
460-3-60
245
125
100
NONE OR DISCONNECT
CONVENIENCE OUTLET
NONE OR DISCONNECT
CONVENIENCE OUTLET
575-3-60
LEGEND
5. Unbalanced 3-Phase Supply Voltage
FLA
—
—
—
Full Load Amps
Locked Rotor Amps
Minimum Circuit Amps
Never operate a motor where a phase imbalance in supply voltage is
greater than 2%. Use the following formula to determine the percentage
of voltage imbalance.
LRA
MCA
max voltage deviation from average voltage
Maximum Overcurrent
Protection
National Electrical Code
Rated Load Amps
MOCP —
% Voltage Imbalance = 100 x
average voltage
NEC
RLA
—
—
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
*Units are suitable for use on electrical systems where voltage supplied to
the unit terminals is not below or above the listed limits.
NOTES:
1. The MCA and MOCP values are calculated in accordance with the NEC,
Article 440.
(224 + 231 + 226)
3
681
3
2. Motor RLA and LRA values are established in accordance with Underwriters’
Laboratories (UL), Standard 1995.
Average Voltage =
=
=
3. The 575-v units are UL, Canada-listed only.
4. Convenience outlet is available as a factory-installed option and is 115-v,
1 ph, 60 Hz.
227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
4
% Voltage Imbalance
= 100 x
= 1.76%
227
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.
13
PRE-START-UP
START-UP
IMPORTANT: Before beginning Pre-Start-Up or Start-Up,
review Start-Up Checklist at the back of this book. The
Checklist assures proper start-up of a unit and provides a
record of unit condition, application requirements, system
information, and operation at initial start-up.
38AUZ Units — The compressor crankcase heater must be
on for 24 hours before start-up. After the heater has been on for
24 hours, the unit can be started. If no time elapsed since the
preliminary charge step was completed, it is unnecessary to
wait the 24-hour period.
PRELIMINARY CHECKS
1. Check that electric power supply agrees with unit
nameplate data.
2. Verify that the compressor crankcase heater is securely in
place.
3. Check that the compressor crankcase heater has been on
at least 24 hours.
4. Recheck for leaks using the procedure outlined in the
Pre-Start-Up section, Leak Test and Dehydration. If any
leaks are detected, repair as required. Evacuate and
dehydrate as described in the Leak Test and Dehydration
section.
5. Ensure that the preliminary charge has been added as
described in the Pre-Start-Up section, Preliminary
Charge.
UNIT DAMAGE HAZARD
Do not attempt to start the condensing unit, even
momentarily, until the following steps have been
completed. Compressor damage may result.
System Check
1. Check all air handler(s) and other equipment auxiliary
components. Consult the manufacturer’s instructions
regarding any other equipment connected to the con-
densing unit. If the unit has field-installed accessories,
be sure all are properly installed and correctly wired. If
used, the airflow switch must be properly installed.
2. Be sure the unit is properly leak checked and dehydrated.
3. Check tightness of all electrical connections.
4. Open the liquid line and suction line service valves.
5. Be sure the unit is properly charged. See “Preliminary
Charge”, on page 9.
6. The electrical power source must agree with the unit’s
nameplate rating.
7. The crankcase heater must be firmly attached to the com-
pressor crankcase. Be sure the crankcase is warm (heater
must be on for 24 hours before starting compressor).
6. All internal wiring connections must be tight, and all
barriers and covers must be in place.
NOTE: The 38AUZ units are factory charged with the
required amount of oil. If recharging in required, use Emka-
rate RL 32-3MAF for the 38AUZ units.
COMPRESSOR ROTATION — On 3-phase units with scroll
compressors, it is important to be certain that the compressor is
rotating in the proper direction. To determine whether or not
compressor is rotating in the proper direction:
1. Connect service gages to the suction and liquid pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the liquid pressure
should rise, as is normal on any start-up.
If the suction pressure does not drop and the liquid pressure
does not rise to normal levels:
1. Turn off power to the unit, tag disconnect.
2. Reverse any two of the unit power leads.
Turn On Crankcase Heater — Turn on the crankcase
heater for 24 hours before starting the unit to be sure all the
refrigerant is out of the oil. To energize the crankcase heater,
proceed as follows:
1. Set the space thermostat set point above the space tem-
perature so there is no demand for cooling.
2. Close the field disconnect.
Preliminary Charge — Before starting the unit, charge
liquid refrigerant into the high side of the system through the
liquid service valve. The amount of refrigerant added must be
at least 80% of the operating charge listed in the Physical Data
table (Tables 1A and 1B, pages 4 and 5). Allow high and low
side pressures to equalize before starting compressor. If
pressures do not equalize readily, charge vapor on low side of
system to assure charge in the evaporator. Refer to GTAC II,
Module 5, Charging, Recover, Recycling, and Reclamation for
liquid charging procedures.
3. Reapply power to the compressor, verify correct
pressures.
The suction and liquid pressure levels should now move to
their normal start-up levels.
COMPRESSOR OVERLOAD — This overload interrupts
power to the compressor when either the current or internal
motor winding temperature becomes excessive, and automati-
cally resets when the internal temperature drops to a safe level.
This overload may require up to 60 minutes (or longer) to reset.
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.
UNIT DAMAGE HAZARD
Prior to starting compressor, a preliminary charge of
refrigerant must be added to avoid possible compressor
damage.
14
ADVANCED SCROLL TEMPERATURE PROTECTION
(ASTP) — Advanced Scroll Temperature Protection (ASTP)
is a form of internal discharge temperature protection, used in
38AUZ*12 and 38AUZ*14 units, that unloads the scroll com-
pressor when the internal temperature reaches approximately
300°F. At this temperature, an internal bi-metal disk valve
opens and causes the scroll elements to separate, which stops
compression. Suction and discharge pressures balance while
the motor continues to run. The longer the compressor runs un-
loaded, the longer it must cool before the bi-metal disk resets.
See Fig. 14.
START UNIT — The field disconnect is closed, the indoor
fan circuit breaker is closed, and the space thermostat is set
above ambient so that there is no demand for cooling. Only the
crankcase heater will be energized.
Reset the space thermostat below ambient so that a call for
cooling is ensured.
Never charge liquid into the low-pressure side of system.
Do not overcharge. During charging or removal of refriger-
ant, be sure indoor-fan system is operating. Ensure both
outdoor fan motors are running; bypass any Motormaster
function.
120
110
100
90
80
70
60
50
40
30
20
10
0
ADJUST REFRIGERANT CHARGE — The unit must be
charged in Cooling mode only. Refer to Cooling Charging
Charts, Fig. 16 through Fig. 19. For applications with line
lengths greater than 100 ft, contact Carrier representative. Vary
refrigerant until the conditions of the chart are met. Note that
the charging charts are different from the type normally used.
The charts are based on charging the units to the correct sub-
cooling 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 out-
door ambient temperature does not affect the reading. Indoor
airflow must be within the unit’s normal operating range. Oper-
ate the unit for a minimum of 15 minutes. Ensure that pressure
and temperature readings have stabilized. Plot the liquid pres-
sure and temperature on chart and add or reduce the charge to
meet the curve. Adjust the charge to conform with the charging
chart, using the liquid pressure and temperature to read the
chart.
0
10
20
30
40
50
60
70
80
90
Compressor Unloaded Run Time (Minutes)
*Times are approximate.
NOTE: Various factors, including high humidity, high ambient tem-
perature, and the presence of a sound blanket will increase cool-
down times.
Fig. 14 — Recommended Minimum Cool-Down Time
After Compressor is Stopped
To manually reset ASTP, the compressor should be stopped
and allowed to cool. If the compressor is not stopped, the motor
will run until the motor protector trips, which occurs up to
90 minutes later. Advanced Scroll Temperature Protection will
reset automatically before the motor protector resets, which
may take up to 2 hours. A label located above the terminal box
identifies Copeland Scroll compressor models (ZP103 and
ZP137) that contain this technology. See Fig. 15.
FINAL CHECKS — Ensure that all safety controls are
operating, control panel covers are on, and the service panels
are in place.
Fig. 15 — Advanced Scroll Temperature
Protection Label
15
Fig. 16 — 38AUZ*07 Charging Chart
Fig. 17 — 38AUZ*08 Charging Chart
Fig. 18 — 38AUZ*12 Charging Chart
16
Fig. 19 — 38AUZ*14 Charging Chart
Fig. 20 — 38AU Wiring Diagram
17
OPERATING SEQUENCE
ROUTINE SYSTEM MAINTENANCE
These items should be part of a routine maintenance program,
to be checked every month or two, until a specific schedule for
each can be identified for this installation:
Base Unit Controls
Indoor (Supply) Fan
The indoor fan contactor (IFC) is remotely located at the fan
coil or fan section. If the thermostat fan operation is selected as
Continuous, the IFC is energized and the indoor (supply) fan
motor runs continuously. If the thermostat fan operation is
selected as Automatic, the IFC will be energized on a call for
Cooling; indoor (supply) fan motor runs. When thermostat call
for Cooling is satisfied, the IFC is de-energized and indoor
(supply) fan motor stops.
Quarterly Inspection (and 30 days after initial
start)
Indoor section
• Condenser coil cleanliness checked.
• Return air filter replacement
• Outdoor hood inlet filters cleaned
• Belt tension checked
Cooling, Unit Without Economizer
• Belt condition checked
On a thermostat call for Cooling, IFC will be energized and
indoor (supply) fan motor runs. Thermostat contact TC1
closes; terminal Y1 at 38AU unit receives 24-v. 24-v received
at CADM terminal Y. If anti-recycle time delay period has not
expired, CADM relay will remain open, preventing
compressor start. When safety pressure switches are closed, the
liquid line solenoid valve opens. When CADM time delay
expires, the compressor contactor is energized; both outdoor
fan motors start and compressor starts.
When space cooling load is satisfied, thermostat contacts TC1
open, removing 24-v at 38AU terminal Y. Compressor and
outdoor fan motors stop. Liquid line solenoid valve is
de-energized and valve closes. CADM begins its three-minute
anti-recycle time delay.
If either the Low Pressure Switch or High Pressure Switch
opens while thermostat contact TC1 remains closed, the
compressor contactor is de-energized (both fan motors and
compressor stop) and liquid line solenoid is de-energized
(valve closes). CADM initiates a TRIP event (cooling demand
sensed at CADM terminal Y but no current is measured at T1,
T2, T3 motor sensors); CADM relay opens and RED LED is
illuminated. TRIP condition maintains lockout of compressor
operation until CADM is manually reset. Reset CADM by
cycling unit main power.
• Pulley alignment checked
• Fan shaft bearing locking collar tightness checked
• Condensate drain checked
Seasonal Maintenance
These items should be checked at the beginning of each season
(or more often if local conditions and usage patterns dictate):
Air Conditioning
• Condenser fan motor mounting bolts tightness
• Compressor mounting bolts
• Condenser fan blade positioning
• Control box cleanliness and wiring condition
• Wire terminal tightness
• Refrigerant charge level
• Evaporator coil cleaning
• Evaporator blower motor amperage
Heating
• Power wire connections
• Fuses ready
• Manual-reset limit switch is closed
Complete system shutdown may be caused by loss of main
power, open compressor internal overload, open low-pressure
or high-pressure switch, or a fault detected by the CADM
logic. Compressor operation without cooling may indicate the
compressor’s ASTP feature is active (unit sizes 12 and 14
only); disconnect unit power and allow compressor to cool. See
Service section for further details.
Economizer or Outside Air Damper
• Inlet filters condition
• Check damper travel (economizer)
• Check gear and dampers for debris and dirt
Cooling, Unit With Economizer
Refer to fan coil unit installation instructions and economizer
accessory installation instructions for operating sequences
when system is equipped with accessory economizer.
Heating
Refer to fan coil unit installation instructions and accessory
heating device installation instructions for operating sequences
in heating mode.
18
SERVICE
POWER
(GRN)
Comfort Alert Diagnostic Module
The Comfort Alert Diagnostic Module (CADM) monitors and
®
analyzes data from the Copeland Scroll three-phase compres-
sor and the thermostat demand. The CADM also provides a
3-minute anti-recycle time delay to compressor cycling.
The CADM detects causes for electrical and system related
failures without any sensors. Flashing LEDs communicate the
Alert codes to guide service technicians in accurately and
quickly troubleshooting the system and determining root cause
for the failure.
ALERT
(YEL)
Inputs to the CADM include 24-vac power, thermostat Y1,
compressor contactor coil (common side) and compressor
power leads (from the compressor contactor).
TRIP
(RED)
Input
Terminal Voltage
Control
Power
Control
Common
Cooling
Contactor
Coil
Line A
Line B
Line C
Fig. 21 — CADM Housing/LED Locations
R
24-V
The ALERT LED indicates an abnormal condition exists in the
system through a flash code. The ALERT LED will blink a
number of times consecutively, pause and the repeat the
process. The number of blinks, defined in Table 6, correlates to
a particular abnormal condition; troubleshooting tips are
provided for each Alert code. Reset of the ALERT may be
automatic or manual. If the fault condition causing the Alert is
self-corrected, the Alert code will be removed and the CADM
will automatically reset and allow the system to restart
normally. Manual reset requires that main power to the 38AU
unit be recycled after the cause for the Alert condition has been
detected and corrected.
The TRIP LED indicates either a time-delay period is currently
active (RED LED is blinking) or the module has locked out the
compressor (RED LED is on steady). A lockout condition will
occur when the CADM detects a thermostat demand at input Y
but there is no power at the compressor line terminals T1 or T2
or T3. This lockout can occur due to a safety switch (LPS or
HPS) opening and de-energizing the compressor contactor, the
compressor-motor internal overload opens, or other internal
power interruption has occurred. Reset of the TRIP LED
requires that unit main power be recycled after the loss of
power to the compressor condition has been detected and
corrected.
C
Y
P
24-V
24-V
24-V
T1
T2
T3
Line
Line
Line
Control of the compressor contactor coil is through a
normally-closed (power on the module) contact between
terminals P and C.
Communications of status and alert conditions is through three
LEDs located on the top edge of the module housing (see Fig.
21): POWER (green), ALERT (yellow), and TRIP (red).
The POWER LED indicates the presence of control power to
the CADM.
Simultaneous Blinking of YELLOW and RED LEDs indicates
control power input to the CADM is low. Check control circuit
transformer and wiring.
Troubleshooting the CADM Wiring – Flashing LEDs also
indicate wiring problems to the CADM. See Table 7 for
discussion of additional LED flash codes and troubleshooting
instructions.
19
Table 6 — LED Status Codes
Status LED
Status LED Description
Status LED Troubleshooting Information
Green “POWER” Module has power
Supply voltage is present at module terminals
Red “TRIP”
LED On Solid
Thermostat demand signal Y 1. Compressor protector is open
is present, but the
2. Condensing unit power disconnect is open
3. Compressor circuit breaker or fuse(s) is open
compressor is not running.
4. Broken supply wires or connector is not
making contact
5. Compressor power wires not routed through
Comfort Alert
6. Compressor contactor has failed open
Red “TRIP” LED The anti-short cycle timer (3 minutes), in module is preventing compressor
Flashing restart.
Module locks out compressor when compressor damaging ALERT code appears.
Lockout ALERT codes are noted in the Status LED Description.
During a compressor lock out, 24VAC power must be removed from module to manually reset.
Yellow “ALERT”
LED On Solid
A short circuit or over current 1. Compressor contactor coil shorted
condition exists on PROT
2. Electrical load too high for PROT circuit
terminal.
(maximum 1 Amp)
3. 24 V AC wired directly to PROT terminal
Yellow “ALERT”
Flash Code 2
System Pressure Trip
Discharge pressure out of
limits or compressor
overload (if no high pressure
switch in system)
1. High head pressure
2. Condenser coil poor air circulation (dirty,
blocked, damaged)
3. Condenser fan is not running
LOCKOUT
4. If low pressure switch is open:
Refer to Code 3 for troubleshooting
Yellow “ALERT”
Flash Code 3
Short Cycling
Compressor is running only
briefly LOCKOUT
1. If low pressure switch is open:
a. Low refrigerant charge
b. Evaporator blower is not running
c. Evaporator coil is frozen
d. Faulty metering device
e. Condenser coil is dirty
f. Liquid line restriction (filter drier blocked if
present)
2. If high pressure switch is open, go to Flash
Code 2 information
3. Intermittent thermostat demand signal
4. System or control board defective
Yellow “ALERT”
Flash Code 4
Locked Rotor
LOCKOUT
1. Low line voltage to compressor
2. Excessive liquid refrigerant in compressor
3. Compressor bearings are seized
Yellow “ALERT”
Flash Code 5
Open Circuit
1. Condensing unit power disconnect is open
2. Compressor circuit breaker or fuses are open
3. Compressor contactor has failed open
4. High pressure switch is open and requires
manual reset
5. Broken supply wires or connector is not
making contact
6. Unusually long compressor protector reset
time due to extreme ambient temperature
7. Compressor windings are damaged
1. Compressor fuse is open on one phase
2. Broken wire or connector on one phase
3. Compressor motor winding is damaged
4. Utility supply has dropped one phase
Yellow “ALERT”
Flash Code 6
Missing Phase
LOCKOUT
Yellow “ALERT”
Flash Code 7
Reverse Phase
LOCKOUT
1. Compressor running backward due to supply
phase reversal
Yellow “ALERT”
Flash Code 8
Welded Contactor
Compressor always runs
1. Compressor contactor has failed closed
2. Thermostat demand signal not connected to
module
Yellow “ALERT”
Flash Code 9
Low Voltage
Control circuit < 18VAC
1. Control circuit transformer is overloaded
2. Low line voltage to compressor
20
Table 7 — CADM Troubleshooting
Miswired Module Indication
Recommended Troubleshooting Action
Green LED is not on,
module does not power up
Determine if both R and C module terminals are
connected. Verify voltage in present at module’s R and C
terminals.
NOTE: The CADM requires a constant nominal 24VAC
power supply. The wiring to the module’s R and C
terminals must be directly from the control transformer.
The module cannot receive its power from another device
that will interrupt the 24VAC power supply. See Fig. 20,
the 38AU Wiring Diagram.
Green LED Intermittent,
module powers up only
when compressor runs
Determine if R and Y terminals are wired in reverse. Verify
module’s R and C terminals have a constant source. See
“NOTE” above for details on R and C wiring.
TRIP LED is on but system
and compressor check OK
Verify Y terminal is wired properly per the 38AU wiring
diagram (see Fig. 19). Verify voltage at contactor coil falls
below 0.5VAC when off. Verify 24VAQC is present across
Y and C when thermostat demand signal is present. If not,
R and C are reverse wired.
TRIP LED and ALERT LED
flashing together
Verify R and C terminals are supplied with 19-28VAC.
ALERT Flash Code 3
(Compressor Short Cycling)
displayed incorrectly
Verify Y terminal is connected to 24VAC at contactor coil.
Verify voltage at contactor coil falls below 0.5VAC when
off.
ALERT Flash Code 5 or 6
(Open Circuit, Missing Phase)
displayed incorrectly
Check that compressor T1 and T3 wires are through
module’s current sensing holes. Verify Y terminal is
connected to 24VAC at contactor coil. Verify voltage at
contactor coil falls below 0.5VAC when off.
Alert Flash Code *
(Welded Contactor)
displayed incorrectly
Determine if module’s Y terminal is connected. Verify Y
terminal is connected to 24VAC at contactor coil. Verify
24VAC is present across Y and C when thermostat
demand signal is present. If not, R and C are reverse
wired. Verify voltage at contactor coil falls below 0.5VAC
when off.
ADVANCED SCROLL TEMPERATURE PROTECTION
(ASTP) — See “Advanced Scroll Temperature Protection
(ASTP)” on page 15.
Crankcase Heater — The heater prevents refrigerant
migration and compressor oil dilution during shutdown when-
ever compressor is not operating. The heater is wired to cycle
with the compressor; the heater is off when compressor is run-
ning, and on when compressor is off.
The crankcase heater will operate as long as the power circuit
is energized.
Low-Pressure Switch — The 38AUZ low-pressure
switch is stem-mounted on the suction line. Switches are all
fixed, non-adjustable type.
High-Pressure Switch — The 38AUZ high-pres-
sure switch is stem-mounted on the discharge line. The switch
is a fixed, non-adjustable type.
Compressor Protection
COMPRESSOR OVERTEMPERATURE PROTECTION
(IP) — A thermostat installed on the compressor motor wind-
ing reacts to excessively high winding temperatures and shuts
off the compressor.
CRANKCASE HEATER — The heater minimizes absorp-
tion of liquid refrigerant by oil in the crankcase during brief or
extended shutdown periods. The main disconnect must be on
to energize the crankcase heater.
Outdoor Fans — Each fan is supported by a formed-wire
mount bolted to the fan deck and covered with a wire guard.
Fan motors have permanently lubricated bearings.
Lubrication
FAN MOTORS have sealed bearings. No provisions are made
for lubrication.
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.
IMPORTANT: Never open any switch or disconnect that
energizes the crankcase heater unless unit is being serviced
or is to be shut down for a prolonged period. After a pro-
longed shutdown on a service job, energize the crankcase
heater for 24 hours before starting the compressor.
21
NOVATION™ Coil Cleaning and Maintenance —
Repairing NOVATION Condenser Tube Leaks
To clean the NOVATION condenser coil, chemicals are NOT
to be used; only water is approved as the cleaning solution.
Only clean potable water is authorized for cleaning
NOVATION condensers.
Clean the coil as follows:
1. Turn off unit power.
2. Remove screws holding rear corner posts and top cover
in place. Pivot top cover up 12 to 18 in. (305 to 457 mm)
and support with a rigid support. See Fig. 21.
RCD offers service repair kit Part Number 50TJ660007 for
repairing tube leaks in the NOVATION coil crosstubes. This kit
includes approved braze materials (aluminum fluxcore braze
rods), a heat shield, a stainless steel brush, replacement fin
segments, adhesive for replacing fin segments, and instructions
specific to the NOVATION aluminum coil. See EPIC for
instruction sheet 99TA526379.
The repair procedure requires the use of MAPP gas and torch
(must be supplied by servicer) instead of conventional
oxyacetylene fuel and torch. While the flame temperature for
MAPP is lower than that of oxyacetylene (and thus provides
more flexibility when working on aluminum), the flame
temperature is still higher than the melting temperature of
aluminum, so user caution is required. Follow instructions
carefully. Use the heat shield.
Replacing NOVATION Condenser Coil
The service replacement coil is preformed and is equipped with
transition joints with copper stub tubes. When brazing the
connection joints to the unit tubing, use a wet cloth around the
aluminum tube at the transition joint. Avoid applying torch
flame directly onto the aluminum tubing.
Field Refrigerant Access Ports
Field service access to refrigerant pressures is through the
access ports located at the service valves (see Fig. 6). These
ports are ¼-in SAE Flare couplings with Schrader check valves
and service caps. Use these ports to admit nitrogen to the field
tubing during brazing, to evacuate the tubing and evaporator
coil, to admit initial refrigerant charge into the low-side of the
system and when checking and adjusting the system refrigerant
charge. When service activities are completed, ensure the
service caps are in place and secure; check for leaks. If the
Schrader check valve must be removed and re-installed, tighten
to 2-3 in-lbs (23-34 N-cm).
Fig. 21 — Pivot and Support Top Cover
3. Carefully remove any foreign objects or debris attached
to the coil face or trapped within the mounting frame and
brackets.
Factory High-Flow Access Ports
There are two additional access ports in the system - on the
suction tube between the compressor and the suction service
valve and on the liquid tube near the liquid service valve (see
Fig. 6). These are brass fittings with black plastic caps. The
hose connection fittings are standard ¼-in SAE Male Flare
couplings.
The brass fittings are two-piece High Flow valves, with a
receptacle base brazed to the tubing and an integral spring-
closed check valve core screwed into the base. (See Fig. 22.)
This check valve is permanently assembled into this core body
and cannot be serviced separately; replace the entire core body
if necessary. Service tools are available from RCD that allow
the replacement of the check valve core without having to
recover the entire system refrigerant charge. Apply compressor
refrigerant oil to the check valve core's bottom o-ring. Install
the fitting body with 96 ±-10 in-lbs (1085 ±23 N-cm) of
torque; do not overtighten.
4. Using a high pressure water sprayer, purge any soap or
industrial cleaners from hose and/or dilution tank prior to
wetting the coil.Clean condenser face by spraying the coil
core steadily and uniformly from top to bottom, directing
the spray straight into or toward the coil face. Do not
exceed 900 psig or a 45 degree angle; nozzle must be at
least 12 in. (30 cm) from the coil face. Reduce pressure
and use caution to prevent damage to air centers (fins).
Do not fracture the braze between air centers and
refrigerant tubes. Allow water to drain from the coil core
and check for refrigerant leaks prior to start−up.
5. Replace top cover and rear corner posts.
PERSONAL INJURY HAZARD
Failure to follow this caution may result in personal injury
or equipment damage.
Chemical cleaning should NOT be used on the aluminum
microchannel condenser. Damage to the coil may occur.
Only approved cleaning is recommended.
22
SEAT
CORE
(Part No. EC39EZ067)
1/2-20 UNF RH
0.596
45°
30°
WASHER
O-RING
DEPRESSOR PERARI720
1/2" HEX
+.01/-.035
.47
5/8” HEX
FROM FACE OF BODY
This surface provides a metal to metal seal when
torqued into the seat. Appropriate handling is
required to not scratch or dent the surface.
7/16-20 UNF RH
Fig. 22 — CoreMax Access Port Assembly
FASTENER TORQUE VALUES
Table 8 — Torque Values
Compressor mounting bolts
65–75 in–lbs
20 ±2 in–lbs
84 ±2 in–lbs
96 ±10 in–lbs
2–3 in–lbs
(734–847 N–cm)
(226 ±23 N–cm)
Condenser fan motor mounting bolts
Condenser fan hub setscrew
High-flow service port
(949 ±136 N–cm)
(1085 ±23 N–cm)
(23–34 N–cm)
Schrader-type service check valve
TROUBLESHOOTING
PROBLEM
SOLUTION
COMPRESSOR DOES NOT RUN
Contactor Open
1. Power off.
1. Restore power.
2. Fuses blown in field power circuit.
3. No control power.
2. After finding cause and correcting, replace with correct size fuse.
3. Check control transformer primary connections and circuit breaker.
4. Check thermostat setting.
4. Thermostat circuit open.
5. Safety device lockout circuit active.
6. Low-pressure switch open.
5. Reset lockout circuit.
6. Check for refrigerant undercharge, obstruction of indoor airflow.
Make sure liquid line solenoid valve(s) is open.
7. High-pressure switch open.
7. Check for refrigerant overcharge, obstruction of outdoor airflow, air
in system. Be sure outdoor fans are operating correctly.
8. Compressor overtemperature switch open.
9. Loose electrical connections.
10. Compressor stuck.
8. Check for open condition. Allow for reset. Replace if defective.
9. Tighten all connections.
10. See compressor service literature.
Contactor Closed
1. Compressor leads loose.
2. Motor windings open.
1. Check connections.
2. See compressor service literature.
3. Single phasing.
3. Check for blown fuse. Check for loose connection at compressor
terminal.
COMPRESSOR STOPS ON HIGH-PRESSURE SWITCH
Outdoor Fan On
1. High-pressure switch faulty.
2. Reversed fan rotation.
3. Airflow restricted.
1. Replace switch.
2. Confirm rotation, correct if necessary.
3. Remove obstruction.
4. Air recirculating.
4. Clear airflow area.
5. Noncondensables in system.
6. Refrigerant overcharge.
7. Line voltage incorrect.
8. Refrigerant system restrictions.
Outdoor Fan Off
5. Recover refrigerant and recharge as required.
6. Recover refrigerant as required.
7. Consult power company.
8. Check or replace filter drier, expansion valve, etc.
1. Fan slips on shaft.
1. Tighten fan hub setscrews.
2. Check power and capacitor.
3. Replace bearings.
2. Motor not running.
3. Motor bearings stuck.
4. Motor overload open.
5. Motor burned out.
4. Check overload rating. Check for fan blade obstruction.
5. Replace motor.
23
TROUBLESHOOTING (cont)
PROBLEM
SOLUTION
COMPRESSOR CYCLES ON LOW-PRESSURE SWITCH
Indoor-Air Fan Running
1. Liquid line solenoid valve(s) fails to open.
1. Check liquid line solenoid valve(s) for proper operation. Replace if
necessary.
2. Filter drier plugged.
3. Expansion valve power head defective.
4. Low refrigerant charge.
Airflow Restricted
2. Replace filter drier.
3. Replace power head.
4. Add charge. Check low-pressure switch setting.
1. Coil iced up.
1. Check refrigerant charge.
2. Clean coil fins.
2. Coil dirty.
3. Air filters dirty.
3. Clean or replace filters.
4. Check damper operation and position.
4. Dampers closed.
Indoor-Air Fan Stopped
1. Electrical connections loose.
2. Fan relay defective.
3. Motor overload open.
4. Motor defective.
1. Tighten all connections.
2. Replace relay.
3. Power supply.
4. Replace motor.
5. Fan belt broken or slipping.
5. Replace or tighten belt.
COMPRESSOR RUNNING BUT COOLING INSUFFICIENT
Suction Pressure Low
1. Refrigerant charge low.
2. Head pressure low.
1. Add refrigerant.
2. Check refrigerant charge. Check outdoor-air fan thermostat settings.
3. Clean or replace filters.
3. Air filters dirty.
4. Expansion valve power head defective.
5. Indoor coil partially iced.
6. Indoor airflow restricted.
Suction Pressure High
4. Replace power head.
5. Check low-pressure setting.
6. Remove obstruction.
1. Unloaders not functioning
2. Heat load excessive.
1. Check unloader adjustments. Check unloader setting.
2. Check for open doors or windows in vicinity of fan coil.
UNIT OPERATES TOO LONG OR CONTINUOUSLY
1. Low refrigerant charge.
1. Add refrigerant.
2. Control contacts fused.
2. Replace control.
3. Air in system.
3. Purge and evacuate system.
4. Clean or replace.
4. Partially plugged expansion valve or filter drier.
SYSTEM IS NOISY
1. Piping vibration.
1. Support piping as required.
2. Compressor noisy.
2. Replace compressor if bearings are worn.
COMPRESSOR LOSES OIL
1. Leak in system.
1. Repair leak.
2. Crankcase heaters not energized during shutdown.
3. Improper interconnecting piping design.
2. Check wiring and relays. Check heater and replace if defective.
3. Check piping for oil return. Replace if necessary.
FROSTED SUCTION LINE
Expansion valve admitting excess refrigerant.
Adjust expansion valve.
HOT LIQUID LINE
1. Shortage of refrigerant due to leak.
1. Repair leak and recharge.
2. Adjust expansion valve.
2. Expansion valve opens too wide.
FROSTED LIQUID LINE
1. Restricted filter drier.
1. Remove restriction or replace.
2. Replace valve.
2. Liquid line solenoid valve partially closed.
24
• Do not install a suction-line filter drier in liquid-line.
• POE oils absorb moisture rapidly. Do not expose oil to
atmosphere.
• POE oils may cause damage to certain plastics and
roofing materials.
APPENDIX
AIR CONDITIONER AND HEAT PUMP WITH
PURON® — QUICK REFERENCE GUIDE
®
• Puron (R-410A) refrigerant operates at 50 percent to
70 percent higher pressures than R-22. Be sure that
servicing equipment and replacement components are
• Wrap all filter driers and service valves with wet cloth
when brazing.
• A factory approved, liquid-line filter drier is required on
every unit.
®
designed to operate with Puron .
®
• Puron refrigerant cylinders are rose colored.
• Recovery cylinder service pressure rating must be 400
• Do not use an R-22 TXV.
psig, DOT 4BA400 or DOT BW400.
• If indoor unit is equipped with a TXV, it must be
®
®
• Puron
systems should be charged with liquid
changed to a Puron TXV.
refrigerant. Use a commercial type metering device in
the manifold hose when charging into suction line with
compressor operating.
• Never open system to atmosphere while it is under a
vacuum.
• When system must be opened for service, recover
refrigerant, break vacuum with dry nitrogen before
opening system.
• Manifold sets should be 700 psig high side and 180 psig
low side with 550 psig low-side retard.
• Use hoses with 700 psig service pressure rating.
• Always replace filter drier after opening system for
service.
• Leak detectors should be designed to detect HFC
refirgerant.
®
• Do not vent Puron into the atmosphere.
®
• Puron , as with other HFCs, is only compatible with
• Do not use capillary tube coils.
POE oils.
• Observe all warnings, cautions, and bold text.
• Vacuum pumps will not remove moisture from oil.
• Use only factory specified liquid-line filter driers with
rated working pressures greater than 600 psig.
®
• All Puron heat pumps must have indoor TXV.
®
• Do not leave Puron suction line driers in place for
more than 72 hours.
25
Copyright 2009 Carrier Corp • 7310 W. Morris St. • Indianapolis, IN 46231
Printed in U.S.A.
Edition Date: 03/09
Catalog No: 38AU-01SI
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Replaces: NEW
26
III. START UP
START-UP CHECKLIST
I. PRELIMINARY INFORMATION
OUTDOOR: MODEL NO.
SERIAL NO.
SERIAL NO.
INDOOR: AIR HANDLER MANUFACTURER
MODEL NO.
ADDITIONAL ACCESSORIES
II. PRE-START-UP
OUTDOOR UNIT
IS THERE ANY SHIPPING DAMAGE?
IF SO, WHERE:
(Y/N)
WILL THIS DAMAGE PREVENT UNIT START-UP?
(Y/N)
CHECK POWER SUPPLY. DOES IT AGREE WITH UNIT?
(Y/N)
HAS THE GROUND WIRE BEEN CONNECTED?
(Y/N)
HAS THE CIRCUIT PROTECTION BEEN SIZED AND INSTALLED PROPERLY?
ARE THE POWER WIRES TO THE UNIT SIZED AND INSTALLED PROPERLY?
(Y/N)
(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)
HAVE FAN AND MOTOR PULLEYS BEEN CHECKED FOR PROPER ALIGNMENT?
(Y/N)
(Y/N)
DO THE FAN BELTS HAVE PROPER TENSION?
(Y/N)
HAS CORRECT FAN ROTATION BEEN CONFIRMED?
(Y/N)
PIPING
ARE LIQUID LINE SOLENOID VALVES LOCATED AT THE INDOOR COILS AS REQUIRED?
(Y/N)
HAVE LEAK CHECKS BEEN MADE AT COMPRESSOR, OUTDOOR AND INDOOR COILS,
TXVs (Thermostatic Expansion Valves), SOLENOID VALVES, FILTER DRIERS, AND FUSIBLE PLUGS
WITH A LEAK DETECTOR?
(Y/N)
LOCATE, REPAIR, AND REPORT ANY LEAKS.
HAVE LIQUID LINE SERVICE VALVES BEEN OPENED?
HAVE SUCTION SERVICE VALVES BEEN OPENED?
(Y/N)
(Y/N)
CHECK VOLTAGE IMBALANCE
LINE-TO-LINE VOLTS:
(AB + AC + BC)/3 = AVERAGE VOLTAGE =
MAXIMUM DEVIATION FROM AVERAGE VOLTAGE =
AB
V
AC
V
BC
V
V
V
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 INDOOR UNIT FAN SPEED AND RECORD.
CHECK OUTDOOR UNIT FAN SPEED AND RECORD.
AFTER AT LEAST 10 MINUTES RUNNING TIME, RECORD THE FOLLOWING MEASUREMENTS:
SUCTION PRESSURE
SUCTION LINE TEMP
LIQUID PRESSURE
LIQUID LINE TEMP
ENTERING OUTDOOR UNIT AIR TEMP
LEAVING OUTDOOR UNIT AIR TEMP
INDOOR UNIT ENTERING-AIR DB (dry bulb) TEMP
INDOOR UNIT ENTERING-AIR WB (wet bulb) TEMP
INDOOR UNIT LEAVING-AIR DB TEMP
INDOOR UNIT LEAVING-AIR WB TEMP
COMPRESSOR AMPS (L1/L2/L3)
/
/
NOTES:
Copyright 2009 Carrier Corp • 7310 W. Morris St. • Indianapolis, IN 46231
Printed in U.S.A.
Edition Date: 03/09
Catalog No: 38AU-01SI
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Pg CL-2
Replaces: NEW
|