Carrier 38AUQ Dimensions and installation guide

Installation, Start-Up
and Service Instructions
CONTENTS
SAFETY CONSIDERATIONS .................... 2
INSTALLATION GUIDELINES .................. 3
INSTALLATION ........................... 7- 16
Step 1 - Plan for Unit Location .................. 7
Step 2 - Complete Pre-Installation Checks ......... 8
Step 3 - Prepare Unit Mounting Support ........... 8
Step 4 - Rig and Mount the Unit ................. 8
Step 5 - Complete Refrigerant Piping Connections... 8
Step 6 - Install Accessories .................... 12
Step 7 - Complete Electrical Connections ......... 12
PRE-START-UP ............................... 17
System Checks .............................. 17
Turn On Crankcase Heaters .................... 17
Preliminary Charge ........................... 17
START-UP .............................. 17 - 20
38AUQ Units ............................... 17
OPERATING SEQUENCE ...................... 21
Indoor (Supply) Fan .......................... 21
Cooling Unit Without Economizer ............... 21
Cooling Unit With Economizer ................. 21
Defrost Cycle ............................... 21
Supplemental Heating/Emergency Heating ........ 22
Cooling and Heating Shutdown ................. 22
ROUTINE SYSTEM MAINTENANCE ............ 22
Quarterly Inspection
(and 30 days after initial start) .................. 22
SERVICE ................................ 23 - 35
Refrigeration System ......................... 23
Compressor Oil .............................. 23
Servicing Systems on Roofs
with Synthetic Materials ....................... 23
Liquid Line Filter Driers ....................... 23
Filed Refrigerant Access Ports .................. 23
Outdoor Coil Metering Devices ................. 23
Refrigerant System Pressure Access Ports ......... 24
Compressor Protection ........................ 24
Crankcase Heater ............................ 24
Commercial Defrost Board ..................... 24
Comfort Alert Diagnostic Module ............... 31
Lubrication ................................. 33
Outdoor Coil Maintenance and
Cleaning Recommendations .................... 33
Service Parts ................................ 35
Fastener Torque Values ........................ 35
TROUBLESHOOTING ......................... 36
APPENDIX A
Air Conditioner and Heat Pump with Puron _n_-
Quick Reference Guide ........................ 37
APPENDIX B
Wiring Diagram List .......................... 37
APPENDIX C
Low Ambient Option -- Factory Installed ......... 38
START-UP CHECKLIST ................... 43 - 44

SAFETY CONSIDERATIONS
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 A'x. 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.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could cause in personal
injury or death.
Before performing service or maintenance operations
on unit, always turn off main power switch to unit and
install lockout tag. Unit may have more than one
power switch.
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
Puron _n>(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.
PERSONAL INJURY AND ENVIRONMENTAL
HAZARD
Failure to follow this warning could cause personal
injury or death.
Relieve pressure and recover all refrigerant before
system repair or final unit disposal.
Wear safety glasses and gloves when handling
refrigerants. Keep torches and other ignitions sources
away from refrigerants and oils.
CUT HAZARD
Failure to follow this caution may result in personal
injury.
Sheet metal parts may have sharp edges or burrs. Use
care and wear appropriate protective clothing, safety
glasses and gloves when handling parts and servicing
38AUQ units.

INSTALLATION GUIDELINE
Replacement/Retrofit -1/22 to Puron ®
Split system heat pumps are intended to be installed with
matching indoor sections only. The 38AUQ heat pump
outdoor units are matched only with same-size 40RUQ
indoor sections. Existing R-22 indoor coils cannot be
converted to Puron <n)R-410A heat pump duty. Only the
existing refrigerant piping is a candidate for retrofit use.
Acid test -If the existing system is being replaced
because of a compressor electrical failure, assume acid is
in system. If system is being replaced for any other
reason, use an approved acid test kit to determine acid
level. If even low levels of acid are detected, install a 100
percent activated alumina suction line filter drier in
addition to the replacement liquid-line filter drier. Operate
this system in COOLING ONLY. Remove the suction line
filter drier as soon as possible, with a maximum of 72 hr
of operation.
Recommendation: Install a ball valve in the liquid line at
the filter drier location when installing a suction filter in
the suction line.
Evaluate existing refrigerant piping -Reuse of existing
refrigerant piping involves three issues: quality (strength) of
existing tubing, cleanliness and tube size. R-410A operates
at pressures that are 50 to 70% higher than the operating
pressures in R-22 systems. It is important that the existing
piping set be in excellent physical condition to be considered
suitable for re-use with R-410A. If the physical condition of
the existing piping set is not excellent, then remove the
existing piping and replace with new piping. Refer to Step 5
for a discussion on selecting pipe sizes for these 38AUQ
heat pumps; refer to Table 2 for recommended pipe sizes.
If the existing piping set is suitable for re-use with
R-410A based on its condition, determine the relative
locations and elevation differences between outdoor
section (38AUQ) and indoor section (40RUQ) and then
check the sizes of the existing lines against the
recommended pipe sizes in Table 2 and the MAXIMUM
vapor riser pipe size use data in Table 3. Do not use pipe
sizes that exceed these maximum vapor riser sizes as oil
return at part load conditions in vertical rises may be an
issue. Replace any riser sections with reduced pipe sizes
if existing pipe sizes exceed these maximum tube size
limits.
Installation -
1. Remove the existing evaporator coil or fan coil and
install the replacement coil.
2. Drain oil from low points and traps in vapor line
tubing if they were not replaced.
3. Remove the existing outdoor unit. Install the new out-
door unit according to these installation instructions.
4. Flush the interconnection piping system with dry
Nitrogen to eliminate as much trace of mineral oil as
possible.
5. Install the factory-supplied liquid-line filter drier at
the indoor coil just upstream of the TXV.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Never install suction-line filter drier in the liquid-line
of a Puron <n_system.
.
7.
8.
If required, install a 100% activated alumina suction
line filter drier at the outdoor unit.
Evacuate and charge the system according to the in-
structions in this installation manual.
Operate the system for 10 hr. In COOLING MODE
ONLY. Monitor the pressure drop across the suction
line filter drier. If pressure drop exceeds 3 psig
(21kPa), replace suction-line and liquid-line filter
driers. Be sure to purge system with dry nitrogen and
evacuate when replacing filter driers. Continue to
monitor the pressure drop across suction-line filter
drier. Repeat filter changes is necessary. Never leave
suction-line filter drier in system longer than 72 hr
(actual time).

CORNER 'B'_
S9-318
[1BO_]
Uf
TOP VIEW
COR_ER "c"
i
THIS BIDE ORLY FOR
38AUE14 _ HSAU_14
_OR_ER "B"
NOTESMINI_UM: CLEARANCE (LOCAL CODES OR JURISDICTIOR _AY
PREVAIL):
A BOTTOM TO COMBUSTIBLE SURFACES: O I_CHES
B OUTDOOR COIL. FOR PROPER AIR FLOW: 36 IRCHES [9!4]
ONE SIDE, I? IRCHES [HOB] THE OTHER THE SIDE GETTING THE
GREATER CLEARARCE IS OPTIONAL
C OVERHEAD: _0 I_CHEB [IBE4], TO ASSURE PROPER OUTBBOB FAN
OPERATIOR
B BETWEER UNITS: CONTROL BOX SIDE, 42 INCHES [IOHl] PER REC
E BETWEE_ UNIT A_D UNGROU_BED SURFACES: CORTROL BOX
SIDE 36 INCHES [914] PER NEC
F BETWEER UNIT A_D BLOC_ OR CONCRETE WALLS ARD OTHER
GROUNDED SURFACES: CONTROL BOX SIDE, 4B IRCHEB [_0_7] PER _EC
WITH EXCEPTION OF THE CLEA_ARCE FOR THE OUTBOOR
COIL AS STATED I_ ROTE IB, A REMOVABLE FENCE
OR BARRICADE REQUIRES NO CLEARANCE
BRITS MAY BE INSTALLED OR COMBUSTIBLE FLOORS MADE
FRO_ WOOB OR CLASS A, B OR C ROOF COVERING MATERIAL
"13-I/4 FACTORY
OUTBOOR COIL _]_
OPTIONAL FACTORY
...............................
6BAGE ACCESS
(4 SIDES} [ll8] [BOB] RIGHT SIDE VIEW
LEFT SIDE VIEW FRONT VIEW
=.
REAR VIEW
UNIT
38AUQ*07
38AUQ*08
38AUQ*12
Standard
Weight
Ibs. kg.
444 201
483 219
575 261
Corner
A
Ibs. kg.
134 61
162 74
186 84
Corner
B
Ibs. kg.
97 44
110 50
126 57
Corner
C
Ibs. kg.
90 41
85 39
106 48
Corner
D
Ibs. kg.
123 56
125 57
157 71
X
23
[584]
2O
[508]
21
[533]
Center of Gravity
Y
26
[660]
24
[61O]
24
[61O]
Z
13
[330]
13
[330]
23
[584]
Unit Height
H
42-3/8
H076]
42-3/8
[1076]
50-3/8
[1280]
Fig. l-38AUQ*07-12 Unit Dimensions C11032

Table 1A -- Physical Data -- 38AUQ*07-12 Units -- 60 Hz English
UNIT SIZE 38AUQ*
NOMINAL CAPACITY (tons)
OPERATING WEIGHTS (Ib)
Aluminum-Fin Coils
REFRIGERANT TYPE $
Operating Charge, Typical (Ib)t
Shipping Charge (Ib)
COMPRESSOR
Qty._Type
OUTDOOR FANS
Qty...Rpm
Motor Hp
Diameter (in)
Nominal Airflow (Cfm Total)
Watts (Total)
07 08 12
6 7.5 10
444 483 575
R-410A
=
18.0 21.0 I 27.0
9.0 9.0 I9.0
1...Scroll 1...Scroll 1...Scroll
2...1100
1/4
22
6,000
610
2...1100
1/4
22
6,000
610
2...1100
1/4
22
6,000
610
OUTDOOR COIL (Oty)
Face Area (sq ft total) 17.5
Rows/Fins per inch (FPI) 2/17
CONTROLS
Pressurestat Settings (psig)
High Cutout 630 _+10
Cut-in 505 _+20
Low Cutout 27 _+3
Cut-in 44 _+5
PIPING CONNECTIONS (in. ODS)
Qty._Vapor 1...11/8
Qty._Liquid 1...3/8
LEGEND
ODS -- Outside Diameter Sweat (socket)
$ Unit isfactory-supplied with partial charge only.
1-Typical operating charge with 25ft of interconnecting piping.
1...Round Tube/Plate Fin (RTPF)
23.0 I28.1
2/17 2/17
630 _+10
505 _+20
27 _+3
44 _+5
1 ...11/8
1...1/2 I
630 _+10
505 _+20
27 _+3
44 _+5
1...13/8
1...1/2

Table 1B -- Physical Data -- 38AUQ*07-12 Units -- 60 Hz SI
UNIT SIZE 38AUQ* 07 08 12
NOMINAL CAPACITY (kW) 21.1 28.4 35.1
OPERATING WEIGHT (kg)
Aluminum-Fin Coils 201 219 281
REFRIGERANT TYPE S R-410A
Operating Charge, Typical (kg) t 8.2 I 9.5 12.2
m
Shipping Charge (kg) 4.1 I 4.1 4.1
1...Scroll I1 Sero,I1Sero,
COMPRESSOR
Qty._Type
OUTDOOR FANS
Oty...r/s
Motor Hp NEMA
Diameter (mm)
Nominal Airflow (L/s)
Watts (Total)
OUTDOOR COIL (Qty)
Face Area (sq mtotal)
Rows/Fins per Meter (Fins/m)
CONTROLS
Pressurestat Settings (kPa)
High Cutout
Cut-in
Low Cutout
Cut-in
2...18 2...18 2...18
1/4 1/4 1/4
560 560 560
2832 2832 2832
610 610 610
1...Round Tube/Plate Fin (RTPF)
I
1.6 I 2.1 2.6
2/670 I2/670 2/670
4344 ±70
3482 ±138
186 ±21
303 ±35
4344 ±70
3482 ±138
186 ±21
303 ±35
I1,,,11/8
1...1/2
PIPING CONNECTIONS (in, ODS)
Qty._Vapor 1...11/8
Qty._Liquid 1 ...3/8
LEGEND
NEMA- National Electrical Manufacturers Association
ODS -- Outside Diameter Sweat (socket)
$ Unit is factory-supplied with partial charge only.
1- Typical operating charge with 7.62 m of interconnecting piping.
4344 ±70
3482 ±138
186 ±21
303 ±35

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
3 8 A U Q A 1 2 A 0 C 6 - 0 A 0 A 0
Model Type
38AU = Carrier Condensing Unit
Puron ® R-410A Refrigerant
Type of Coil
Q = Heat Pump Scroll Compressor
Refrigerant Options
A = None
B = Low Ambient
Nominal Tonnage
07 = 6 Tons
08 = 7.5 Tons
12 = 10 Tons
Not Used
A = Not Used
Not Used
0 = Not Used
Coil Options
A = AI/Cu
B = Precoat AI/Cu
C = E-Coat AI/Cu
E= Cu/Cu
M = AI/Cu with Hail Guard
N = Precoat AI/Cu with Hail Guard
P = E-Coat AI/Cu with Hail Guard
R = Cu/Cu with Hail Guard
Packaging
0 = Standard
1 = LTL
Electrical Options
A = None
C = Non-Fused Disconnect
Service Options
0 = None
1 = Un-powered Convenience Outlet
2 = Powered Convenience Outlet
Not Used
A = Place Holder
Base Unit Controls
0 = Electro-Mechanical Controls
Design Revision
A = Initial Rev (Discrete Model Number)
Voltage
1 = 575/3/60
5 = 208/230/3/60
6 = 460/3/60
Cl1033
Fig. 2- Model Number Nomenclature
POSITION NUMBER
TYP CAL
POSITION
1-2
3-4
5
6-10
DESIGNATES
Week of manufacture (fiscal calendar)
Year of manufacture ('11" = 2011 )
Manufacturing location (G = ETR Texas, USA)
Sequential number
Fig. 3 - Serial Number Nomenclature Cl1034
.INSTALLATION
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National
Electrical Code) ANSI/NFPA 70 for special installa-
tion requirements.
2. Determine unit location (from project plans) or select
unit location.
3. Check for possible overhead obstructions which may
interfere with unit lifting or rigging.
Step 1 mPlan 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.
Select a unit mounting system that provides adequate
height to allow for removal and disposal of frost and ice
that will form during the heating-defrost mode.
NOTE: Consider also the effect of adjacent units on
airflow performance and control box safety clearance.

Donotinstall 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.
Evaluate the path and required line length for
interconnecting refrigeration piping, including vapor riser
requirements and liquid line lift; a heat pump system will
have one of each type in opposite modes. Relocate
sections to minimize the length of interconnecting tubing.
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.
i RI G HT:
REAR t_ Min 18'' (457 mm)
Uin 18" (457 mm) IW [11 s, 1 requried for service
e0.ed,oe1..... /
ELT: - ....
requneo [or serwce .... <:
Note: Observe requirements for 39" (914 mm) operating clearance
on either Left or Rear coil opening.
C11035
Fig. 4 -Service Clearance Dimensional Drawing
Step 2 1Complete Pre-Installation Checks
Check Unit Electric Characteristic i
Confirm before installation of unit that voltage, amperage
and circuit protection requirements listed on unit data plate
agree with power supply provided.
Un-crate Unit i
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.
Inspect Shipment i
File a claim with shipping company if the shipment is
damaged or incomplete.
Consider System Requirements i
• 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.
• Locate the unit so that the outdoor coil (condenser)
airflow is unrestricted on all sides and above.
• 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.
NOTE: If vibration isolators are required for a particular
installation, use the data in Fig. 1 to make the proper
selection.
Step 3 1Prepare Unit Mounting Support
Slab Mount i
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 4 1Rig and Mount the Unit
Rigging i
These units are designed for overhead rigging. Refer to
the rigging label for preferred rigging method. Spreader
bars are not required if top crating is left on the unit. All
panels 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.
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.
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.
Step 5 1 Complete Refrigerant Piping
Connections
Refrigerant lines must be carefully designed and
constructed to ensure equipment reliability and efficiency.
Line length, pressure drop, compressor oil return, and
vertical separation are several of the design criteria that
must be evaluated. See Table 2.
IMPORTANT: Do not bury refrigerant piping
underground.
IMPORTANT: A refrigerant receiver is not
provided with the unit. Do not install a receiver.

Table2-38AUQ*07-12 Piping Recommendations (Single-Circuit Unit)
R-410A Equivalent Length
Ft 0-38 38-75 75-113 113-150
Model Length Linear 0-25 25-50 50-75 75-100
Nominal Capacity Length Equiiv 0-38 38-75 75-113 113-115
38AUQ*07 Liquid Line 3/8 3/8 3/8 1/2 3/8 1/2
Max Lift
Cool 25 50 48 75 39 100
Heat 25 50 48 80 31 80
Vapor Line 7/8 7/8 1-1/8 1-1/8
Charge (Ibs) 17.8 18.8 20.3 22.8 21.4 24.5
38AUQ*08 Liquid Line 1/2 1/2 1/2 1/2
Max Lift
Cool 25 50 75 1O0
Heat 25 50 60 60
Vapor Line 7/8 1-1/8 1-1/8 1-1/8 1-1/8
Charge (Ibs) 20.9 23.0 24.9 26.8
38AUQ*12 Liquid Line 1/2 1/2 1/2 1/2 8/8
Max Lift
Cool 25 50 75 85 1O0
Heat 25 50 60 60 60
Vapor Line 7/8 1-1/8 1-1/8 1-1/8 1-1/8 1-3/8
Charge (Ibs) 26.8 28.8 30.7 33.4 37.2
Legend:
Length Equiv Equivalent tubing length, including effects of refrigeration specialties devices
Liquid Line Tubing size, inches OD.
Max Lift Maximum liquid lift at maximum permitted liquid line pressure drop
Cooling ° Indoor unit ABOVE outdoor unit
Heating ° Indoor unit BELOW outdoor unit
Vapor Line Tube size, inches OD
Charge Charge Quantity, Ibs. Calculated for both liquid line sizes (where applicable), but only with large
suction line size (where applicable)
NOTE: For applications with linear length greater than 100 ft (30.5 m), contact your local Carrier
representative.
Check Vertical Separation i
If there is any vertical separation between the indoor and
outdoor units, check to ensure that the separation is within
allowable limits. Relocate equipment if necessary.
Provide Safety Relief I
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.
Refrigerant Line Sizing i
Consider the length of the piping required between the
outdoor and indoor units. The maximum allowable line
length is 100 ft (30.5 m). See Table 2. Refrigerant vapor
piping should be insulated.
Risers in Heat Pump Piping Systems i
Elevation differences between the outdoor unit and the
indoor unit in heat pump systems will create two riser line
conditions - one in the liquid line in one mode and one in
the vapor line in the opposite mode. See the following
table to identify which lines are risers in this installation.
38AUQ Unit 38AUQ Unit
Mode BELOW ABOVE
ID Unit ID Unit
Riser in Riser in
Vapor
Cooling Liquid (Suction Gas)
Vapor
Heating (Discharge Gas) Liquid
Liquid Line Riser: Refer to Pipe Sizing Table, Table 2;
observe Max Lift limits for liquid line according to unit
mode, equivalent line length and pipe size.
Vapor Line Riser: Refer to Table 3 for maximum pipe
size in single pipe vapor risers. All pipe size
recommendations in Pipe Sizing Table, Table 2, satisfy
these maximum vapor line sizes. If this installation is
re-using existing piping, check the vapor line sizes
against these maximum values; replace riser sections with
these pipe sizes if necessary.

Table3-Maximum Vapor Line Sizes
38AUQ Unit 38AUQ Unit
38AUQ BELOW ABOVE
Size ID Unit ID Unit
Max Diameter, Single Pipe (in.)
07 1 -1/8 1-5/8
08 1-3/8 1-5/8
12 1-5/8 1-5/8
Table 4 - Puron-duty Filter Drier(s)
Model-Size Qty Liquid
Line OD
38AUQ*07 1 3/8-in
38AUQ*08 1 1/2-in
38AUQ* 12 1 1/2_in
Desiccant Part
Volume Number Ref
8 cu. in. KH43LG088
16 cu. in. KH43LG089
16 cu. in. KH43LG089
Table 5-Refrigerant Specialties Part Numbers
LIQUID LINE LIQUID LINE SOLENOID SIGHT FILTER
SIZE (in,) SOLENOID VALVE (LLSV) COIL GLASS DRIER
3/8 EF680033 plus EF680039 biflow kit EF680037 KM680008
1/2 EF680035 plus EF680039 biflow kit EF680037 KM680004 Provided with unit
See Table 4
5/8 EF680036 plus EF680039 biflow kit EF680037 KM680005
Install Filter Drier and Moisture Indicator --
Every unit MUST have a bi-directional filter drier in the
liquid line. Locate the filter drier(s) at the indoor unit, close
to the indoor coil's thermal expansion valve (TXV) inlets.
38AUQ units include one Puron-duty filter drier, shipped
in cartons attached to the unit basepan. Remove the filter
drier and prepare to install in the liquid line at the indoor
coil. Do not remove connection fitting plugs until ready to
connect and braze the filter drier into the liquid line
position. See Table 4.
IMPORTANT: A refrigerant receiver is not
provided with the unit. Do not install a receiver.
Installation of liquid line moisture indicating sightglass in
each circuit is recommended. Locate the sightglass(es)
between the outlet of the filter drier and the TXV inlet.
Refer to Table 5 for recommendations on refrigeration
specialties.
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 vapor service valves at the outdoor unit.
Install Liquid Line Solenoid Valves m
It is recommended that a bi-directional solenoid valve be
placed in the main liquid line (see Figs. 5 & 6) between
the outdoor unit and the indoor coil. Locate the solenoid
valve at the end of the liquid line, near the outdoor unit
connections, with flow direction arrow pointed at the
outdoor unit. Refer to Table 5. (A liquid line solenoid
valve is required when the liquid line length exceeds 75 ft
[23 m].) This valve prevents refrigerant migration (which
causes oil dilution) to the compressor during the off cycle,
at low outdoor ambient temperatures. Wire the solenoid
according to the unit label diagram.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Failure to use a solenoid valve relay (SVR) PNO
HN61PC005 may cause overload of Comfort Alert
Diagnostic Module (CADM) and compressor alarm
lock out.
CAPACITY CONTROL LIQUID LINE SOLENOID
VALVE - 38AUQ units are single-stage only designs. DO
NOT USE a capacity control liquid line solenoid valve on
the indoor coil.
EQUALIZERLINE
TXV
INDOOR SENSING
COIL CKT BULB SIGHTGLASS
A LOCATION
FILTERDRIER
A LOCATION
AIRFLOW J'
LEGEND
TXV -- Thermostatic Expansion Valve
C11036
Fig. 5- Location of Sight Glass(es) and Filter Driers
(typical 38AUQ size 07 & 08)
10