Trane 4PXCBU36BS3HAC Assembly instructions

Installer’s Guide
ALL phases of this installation must comply with NATIONAL, STATE AND LOCAL CODES
IMPORTANT — This Document is customer property and is to remain with this unit. Please return to service information pack
upon completion of work.
2. INDOOR UNIT AIRFLOW
Indoor unit must provide the required airflow for the heat
pump or cooling combinations approved for this coil.
IMPORTANT: Review your installation requirements. Check
the table on the outline drawing and note all dimensions for
your coil before beginning the installation.
Table of Contents
General .................................................................................1
Application Information ......................................................1
Recommendation ................................................................2
Furnace in Upow Position ................................................2
Furnace in Downow Position ...........................................2
Installing / Brazing Refrigerant Lines................................3
Leak Check...........................................................................3
Condensate Drain Piping....................................................4
Cleaning the Coil .................................................................4
Outline Drawing...................................................................5
Troubleshooting Indoor TXV / Cooling Mode ...................6
Figure 1
18-AD43D1-1A-EN
Cased Aluminum Coil "Dedicated Upow"
Convertible to horizontal with separately purchased kit
Upow model:
4PXCBU36BS3HAC
NOTE:
OPTIONAL DOWNFLOW GASKET INSTALLATION: For
unusually humid applications that expect prolonged
operation above 70% RH, it is recommended to use the
BAYGSKT001A0 gasket kit to prevent water from forming
on the bottom of the drain pan and dripping into the
supply ductwork.
NOTE: 4PXC upow coils may be installed in Upow, Down-
ow, Horizontal Right with kit, and Horizontal Left with kit.
1. FURNACE AND COIL
The coil MUST BE installed downstream (in the outlet air)
of the furnace.
WARNING
!
This product can expose you to chemicals including
lead, which are known to the State of California to case
cancer and birth defects or other reproductive harm.
For more information go to www. P65Warnings.ca.gov
A. GENERAL
This coil is designed for use in combination with a heat pump or
cooling outdoor section using R-410A REFRIGERANT.
The 4PXC equipment has been evaluated in accordance with
the Code of Federal Regulations, Chapter XX, Part 3280 or the
equivalent. “Suitable for Mobile Home use” The height of the
Furnace, Coil and discharge duct work must be 7 ft. or less.
Inspect the coil for shipping damage. Notify the transportation
company immediately if the coil is damaged.
B. APPLICATION INFORMATION
WARNING (Medium/high pressure)
Contains Refrigerant!
System contains oil and refrigerant under high pressure.
Recover refrigerant to relieve pressure before opening the
system. See unit nameplate for refrigerant type. Do not
use non-approved refrigerants, refrigerant substitutes, or
refrigerant additives.
Failure to follow proper procedures or the use of non-
approved refrigerants, substitutes, or refrigerant additives
could result in death, serious injury, or equipment damage.
WARNING
!

2 18-AD43D1-1A-EN
Installer’s Guide
CAUTION
!
This coil is pressurized with 8-12 psig of dry air. Do
not stand directly in front of the coil connections when
removing sealing plugs. If no pressure is released, check
for leaks.
C. RECOMMENDATION
If a coil is part of the total system installation, use the Installer’s
Guide packaged with the furnaces, outdoor sections, and ther-
mostat for physically installing those components.
UPFLOW
FURNACE
CASED
COIL
SCREWS
(BO
TH SIDES)
SELF TAPPING SCREWS (4)
1-1/2” MAXIMUM
FIELD SUPPLIED
FOR UPFLOW /
HORIZONTAL LEFT
INSTALLATIONS
E. FURNACE IN DOWNFLOW POSITION
1. DOWNFLOW GAS FURNACE
When a coil is used with a downflow furnace, a subbase
is not required between the coil case and combustible
flooring.
a. Place the coil case on the furnace supply air plenum.
b. Secure the coil case to the plenum.
c. Set the furnace on top of the coil case, making sure
that the back side of the discharge opening is snug up
against the duct flange at the top rear of the coil case.
d. Secure the coil case to the furnace and seal for air
leaks as required.
CAUTION
!
This coil is pressurized with 8-12 psig of dry air. Do
not stand directly in front of the coil connections when
removing sealing plugs. If no pressure is released, check
for leaks.
D. FURNACE IN UPFLOW POSITION
APPLICATION USES UPFLOW COIL MODEL ONLY
IMPORTANT:
If installing the coil in the horizontal position, you MUST
use the horizontal kit listed below for this coil model num-
ber and follow the instructions in the installation guide
provided with the conversion kit.
Model Number Horizontal Kit No.
4PXCBU36BS3HAC BAYCONV23B
Figure 2
Figure 3
Attach Downow
Bottom Gasket
Start
here
a. Lay the coil on its back side.
b. Locate the 4" wide gasket material found in
BAYGSKT001A0.
c. Attach the 4" gasket material to three sides of the
bottom of the drain pan as shown. Make sure to
start by matching up the edge of the gasket mate-
rial to the inner edge of the drain pan by the coil fins
and working outwards.
d. The gasket material can be cut or ripped easily so that
it can be tailored to fit. The gasket material must cover
the three sides along the entire length of the coil as
shown in Figure 3.
NOTE:
4PXC upow coil may be installed in Upow, Downow,
Horizontal Right with kit, and Horizontal Left with kit.
1. UPFLOW GAS FURNACE
a. Apply gasket material (duct seal field supplied) to ALL
mating surfaces between the furnace and the coil case.
b. Set the coil case on top of the furnace. Connect the
ductwork to the coil case using field supplied screws.
See Figure 2.
c. Secure the coil case to the furnace and seal for air
leaks as required.
2. DOWNFLOW GASKET INSTALLATION (OPTIONAL):
For unusually humid applications that expect prolonged
operation above 70% RH, it is recommended to use the
BAYGSKT001A0 gasket kit to prevent water from forming
on the bottom of the drain pan and dripping into the supply
ductwork.

18-AD43D1-1A-EN 3
Installer’s Guide
IMPORTANT:
Do not unseal refrigerant tubing until ready to t refrigerant
lines.
There is only a holding charge of dry air in the indoor coil, therefore
no loss of operating refrigerant charge occurs when the sealing
plugs are removed.
F. INSTALLING / BRAZING REFRIGERANT LINES
Do NOT open refrigerant valve at the outdoor unit until the
refrigerant lines and coil have been brazed, evacuated, and
leak checked. This would cause contamination of the refriger-
ant or possible discharge of refrigerant to the atmosphere.
1. The following steps are to be considered when installing
the refrigerant lines:
a. Determine the most practical way to run the lines.
b. Consider types of bends to be made and space
limitations.
c. Route the tubing making all required bends and
properly secure the tubing before making final
connections.
NOTE: Refrigerant lines must be isolated from the structure and
the holes must be sealed weather tight after installation.
NOTE:
The TXV setting on this unit may run high superheat
(15-25°F) by design when measured at the outdoor unit.
Figure 4
Note: When installing coil onto an S-Series furnaces
in horizontal right or downow conguration, bend
the anges downward for a ush t.
CAUTION
!
NOTE:
TXV bulb MUST be protected (wrapped with wet rag) or
removed, while brazing the tubing. Overheating of the
sensing bulb will affect the functional characteristics and
performance of the comfort coil.
When replacing the TXV bulb, reinstall the bulb in the
proper orientation.
9. Wrap the TXV with insulation after the spring clip has been
installed.
G. LEAK CHECK
1. Using a manifold gauge, connect an external supply of dry
nitrogen to the gauge port on the liquid line.
2. Pressurize the connecting lines and indoor coil to 150 PSIG
maximum.
3. Leak check brazed line connections using soap bubbles.
Repair leaks (if any) after relieving pressure.
4. Evacuate and charge the system per the instructions packaged
with the outdoor unit.
Figure 5
Capillary tubes will come
out the top of bulb when
positioned correctly.
PAINTED AREAS OF THE UNIT MUST BE SHIELDED DURING
BRAZING.
1. Remove both rubber plugs from the indoor coil.
2. Field supplied tubing should be cut square, round and free
of burrs at the connecting end. Clean the tubing to prevent
contaminants from entering the system.
3. Run the refrigerant tubing into the stub tube sockets of the
indoor unit coil.
4. Flow a small amount of nitrogen through the tubing while
brazing.
5. Use good brazing technique to make leakproof joints.
6. Minimize the use of sharp 90 degree bends.
7. Insulate the suction line and its fittings.
8. Do NOT allow un-insulated lines to come into contact with
each other.

4 18-AD43D1-1A-EN
Installer’s Guide
Figure 6
I. CLEANING THE COIL
The two piece door allows removal of the outer casing doors
without interference from refrigerant or condensate lines.
The foil covered insulation on 4PXC coils should be wiped down
and residual dirt and dust should be vacuumed up to maintain
good air quality. See Figure 6.
The manufacturer’s recommendation for coil cleaning is to initially
use only water to wash away debris that may have collected on
and in the coil fin surface.Removing an evaporator coil is the best
way to effectively clean a coil that is heavily contaminated. This
is accomplished by removing the coil from the cabinet, sealing
the liquid and vapor line and using a strong water stream such
as from a garden hose, being careful to prevent fin damage. Use
chemical cleaners, only when necessary.
H. CONDENSATE DRAIN PIPING
Condensate drain connections are located in the drain pan at
the bottom of the coil/enclosure assembly. The female threaded
fitting protrudes outside of the enclosure for external connection.
A field fabricated trap is not required for proper drainage due to
the positive pressure of the furnace; however, it is recommended
to prevent efficiency loss of conditioned air.
1. The drain hole in the drain pan must be cleared of all insulation.
2. Insulate the primary drain line to prevent sweating where
dew point temperatures may be met. (Optional depending on
climate and application needs)
3. Connect the secondary drai n line to a separate drain line (no
trap is needed in this line).
NOTE:
Refer to Service Guideline, UN-SVG001C-EN, Evaporator
Coil Cleaning and Condensate Drain Maintenance Guide-
lines for important information on cleaning coils with
chemical treatments.

18-AD43D1-1A-EN 5
Installer’s Guide
MODEL 4PXCBU36BS3
SHIPPING WEIGHT (LBS.)54
REFRIGERANT CONTROL HEIGHT "A" (IN.) 22 - 1/2
OVERALL WIDTH "B" (IN.) 17 - 1/2
OPENING WIDTH "C" (IN.) 16 - 5/8
TOP OPENING "D" 15 - 3/4
GAS CONNECTION
LIQUID CONNECTION MATCHED FURNACE WIDTH (NO ADAPTER RQUIRED) 17 - 1/2
DRAIN PA N PLASTIC
TXV (NON-BLEED)
7/8 3/8
From Dwg D346711 RevB
Outline Drawing for Upflow model:
4PXCBU36BS3HAC

6 18-AD43D1-1A-EN
Installer’s Guide
Is sub cooling at the
outdoor unit between
8 to 12F?
Troubleshooting Indoor TXV / Cooling Mode
NO
YES Is superheat
< 5F? YES
Correct air
flow
problem
Is air flow at least
350 CFM per ton?
YES
NO
Remove sensing bulb from the
suction line. Measure superheat
at indoor coil while holding the
bulb in bare hand for one minute.
Does superheat decrease?
Measure superheat at indoor coil
while placing the bulb in an ice
and water bath for one minute.
Does superheat increase?
YES
Replace the
TXV
TXV is OK
NO
Is superheat
< 25F? YES
NO
Is indoor
temperature more
than 85F?
NO
Is sub cooling less
than 8F?
YES
Confirm that charge
is correct and look
for dirty or restricted
outdoor coil.
Confirm that
charge is
correct.
NO
Before starting, insure the
blower wheel, indoor and outdoor
coils are clean.
Is the liquid line
temperature at indoor
coil within 8F of outdoor
liquid line temperature?
YES
Verify line set is
sized properly
for application
NO
The system is running at max
capacity and this may be
causing the High superheat.
Wait until indoor temperature
is less than 80F and check
superheat again.
YES
YES
Verify Inlet screen
of inlet tube
assembly is clear
of debris
NO
Verify Inlet screen
of inlet tube
assembly is clear
of debris
NO

18-AD43D1-1A-EN 7
Installer’s Guide

About Trane and American Standard Heating and Air Conditioning
Trane and American Standard create comfortable, energy efficient indoor environments for residential applications.
For more information, please visit www.trane.com or www.americanstandardair.com
The manufacturer has a policy of continuous data improvement and it reserves the right to change design and specifications without notice. We are
committed to using environmentally conscious print practices.
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18-AD43D1-1A-EN 03 Nov 2021
Supersedes (New)