Lennox TPA036H4N4, TPA042H4N4, TPA048H4N4, TPA060H4N4 Installation Instructions Manual

INSTALLATION

2011 Lennox Industries Inc.

Dallas, Texas, USA

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.

WARNING

Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.

Installation and service must be performed by a qualified
installer or service agency.

IMPORTANT

The Clean Air Act of 1990 bans the intentional venting of
refrigerant (CFCs, HFCs, and HCFCs) as of July 1,

1992. Approved methods of recovery, recycling or
reclaiming must be followed. Fines and/or incarceration
may be levied for noncompliance.

IMPORTANT

This unit must be matched with an indoor coil as
specified in Lennox’ Engineering Handbook. Coils
previously charged with HCFC−22 must be flushed

NOTICE TO INSTALLER

It is critical for proper unit operation to place outdoor unit on an
elevated surface as described in Unit Placement section on page 8.

It is critical for proper defrost operation to set the defrost termination
pins (P1) on the defrost control prior to starting system. See Defrost
System section on page 31 for further details.

BRAZING LINE SET TO SERVICE VALVES

It is imperative to follow the brazing technique illustrated starting on
page 10 to avoid damaging the service valve’s internal seals.

UNIT PLACEMENT

DEFROST OPERATION

INSTRUCTIONS

T−CLASSt TPA*H4 Units

G and Y Voltage

HEAT PUMP UNITS

506650−01
02/11
Supersedes 11/10

TABLE OF CONTENTS

Shipping and Packing List 1. . . . . . . . . . . . . . . . . . . . . .

General 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Model Number Identification 2. . . . . . . . . . . . . . . . . . . . . .

Typical Unit Parts Arrangement 3. . . . . . . . . . . . . . . . . . .

Operating Gauge Set and Service Valves 4. . . . . . . . . . .

Recovering Refrigerant from Existing System 6. . . . . . .

New Unit Placement 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

New or Replacement Line Set 8. . . . . . . . . . . . . . . . . . . . .

Brazing Connections 10. . . . . . . . . . . . . . . . . . . . . . . . . . .

Flushing Line Set and Indoor Coil 13. . . . . . . . . . . . . . . .

Installing Indoor Metering Device 14. . . . . . . . . . . . . . . .

Leak Test Line Set and Indoor Coil 15. . . . . . . . . . . . . . .

Evacuating Line Set and Indoor Coil 16. . . . . . . . . . . . .

Electrical 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Servicing Unit Delivered Void of Charge 22. . . . . . . . . . .

Start−Up 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Refrigerant 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Operation 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Defrost System 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maintenance 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Checklist 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Shipping and Packing List

Check the unit for shipping damage and that all included
items listed below are intact. If damaged, or if parts are
missing, immediately contact the last carrier.

1  Assembled outdoor unit

1  Liquid line bi−flow filter drier

General

T−Class TPA*H4 Heat Pumps, which will also be
referred to in this instruction as the outdoor unit uses
HFC−410A refrigerant. This outdoor unit, must be installed
with a matching indoor unit and line set as outlined in the
Lennox Engineering Handbook. TPA*H4 Heat Pumps are
designed for use in check expansion valve (CTXV)
systems.

Litho U.S.A.

02/11 506650−01

*2P0211* *P506650-01*

Page 1

Unit Dimensions − inches (mm)

INLET
AIR

INLET AIR

TOP VIEW

A

INLET AIR

INLET AIR

VAPOR LINE
CONNECTION

LIQUID LINE
CONNECTION

B

OPTIONAL UNIT

STAND-OFF KIT (4)

(FIELD−INSTALLED)

COIL DRAIN OUT-

LETS (AROUND PERI-

METER OF BASE)

OUTDOOR COIL

COMPRESSOR

4-3/8
(111)

6-3/8
(162)

FAN

4-3/8
(111)

Compressor

6-3/8
(162)

TOP VIEW BASE SECTION

A

4-3/8
(111)

4-3/8
(111)

DISCHARGE
AIR

4-3/8
(111)

4-3/8
(111)

Electrical

VAPOR AND
LIQUID LINE

CONNECTIONS

2-3/4 (70)

SIDE VIEW

Inlets

2 (51)

3/4 (19)

Model Numbers A B

TPA036H4N4

TPA042H4N4

TPA048H4N4

TPA060H4N4

32−1/4 (819) 29−1/4 (743)

32−1/4 (819) 37 (940)

32-1/4 (819) 37 (940)

32-1/4 (819) 43−1/4 (1099)

Model Number Identification

TPA Y1036 H 44 N

T = T−Class Product Line

P = Heat Pump Outdoor Unit

Brand/Family

Unit Type

Major Design Sequence

A = 1st Generation

B = 2nd Generation

Nominal Cooling Capacity − Tons

036 = 3 Tons

042 = 3.5 Tons

048 = 4 Tons
060 = 5 Tons

Cooling Efficiency

H = High Efficiency

Minor Design Sequence

1 = 1st Revision
2 = 2nd Revision
3 = 3rd Revision

Coil type

4 = Four−sided

Part Load Capability

N = No part load, single stage compressor

Refrigerant Type

4 = HFC−410A

SIDE VIEW

Vol ta ge

Y = 208/230V-3 phase-60hz
G = 460V-3 phase-60hz

OPTIONAL UNIT
STAND-OFF KIT (4)
(FIELD−INSTALLED)

506650−01

Page 2

Typical Unit Parts Arrangement

SINGLE

RUN

CAPACITOR

(C12)

GROUND

LUG

CONTACTOR

CUTOUT FOR HIGH

VOLTAGE CONDUIT

(K1)

CONTROL BOX

NOTE  PLUMBING LAYOUT AND
COMPRESSOR TYPE MAY VARY SLIGHTLY
BETWEEN MODEL SIZES.

FAN RELAY (K10) (G−VOLTAGE
UNITS ONLY)

COMPRESSOR

HARNESS

DEFROST CONTROL
(A108)

DISTRIBUTOR

CHECK EXPANSION

CONTROL WIRE
LOOP

LINE FILTER DRIER

EQUALIZER LINE

CRANKCASE HEATER

LIQUID LINE SERVICE

VALV E

BI−FLOW LIQUID

TRUE SUCTION

HIGH PRESSURE

THERMOSTAT (S40)

PORT

SWITCH (S4)

VALV E

MUFFLER

COMPRESS0R

DISCHARGE
LINE

LOW PRESSURE
SWITCH (S87)

REVERSING
VALVE (R1)

CHECK
EXPANSION
VALV E
SENSING BULB

CRANKCASE
HEATER (HR1)

REVERSING VALVE
SOLENOID

VAPOR LINE
SERVICE VALVE

COIL SENSOR (RT21) IS

LOCATED ON HAIRPIN

SHOWN. SIXTH HAIRPIN

UP ON INSIDE ROW

AMBIENT TEMPERATURE
SENSOR (RT13)

Figure 1. Typical Unit Parts Arrangement

Page 3

TPA*H4 SERIES

CAUTION

IMPORTANT

Physical contact with metal edges and corners while
applying excessive force or rapid motion can result in
personal injury. Be aware of, and use caution when
working near these areas during installation or while
servicing this equipment.

Operating Gauge Set and Service Valves

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation.

TORQUE REQUIREMENTS

When servicing or repairing heating, ventilating, and air
conditioning components, ensure the fasteners are
appropriately tightened. Table 1 lists torque values for
fasteners.

IMPORTANT

Only use Allen wrenches of sufficient hardness (50Rc −
Rockwell Harness Scale minimum). Fully insert the
wrench into the valve stem recess.

Service valve stems are factory−torqued (from 9 ft−lbs for
small valves, to 25 ft−lbs for large valves) to prevent
refrigerant loss during shipping and handling. Using an
Allen wrench rated at less than 50Rc risks rounding or
breaking off the wrench, or stripping the valve stem
recess.

See the Lennox Service and Application Notes #C−08−1
for further details and information.

To prevent stripping of the various caps used, the
appropriately sized wrench should be used and fitted
snugly over the cap before tightening.

When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. Table 1 provides
torque values for fasteners.

Table 1. Torque Requirements

Parts Recommended Torque

Service valve cap 8 ft.− lb. 11 NM

Sheet metal screws 16 in.− lb. 2 NM

Machine screws #10 28 in.− lb. 3 NM

Compressor bolts 90 in.− lb. 10 NM

Gauge port seal cap 8 ft.− lb. 11 NM

USING MANIFOLD GAUGE SET

When checking the system charge, only use a manifold
gauge set that features low loss anti−blow back fittings.

Manifold gauge set used with HFC−410A refrigerant
systems must be capable of handling the higher system
operating pressures. The gauges should be rated for use
with pressures of 0 − 800 psig on the high side and a low
side of 30" vacuum to 250 psig with dampened speed to
500 psi. Gauge hoses must be rated for use at up to 800
psig of pressure with a 4000 psig burst rating.

OPERATING SERVICE VALVES

The liquid and vapor line service valves are used for
removing refrigerant, flushing, leak testing, evacuating,
checking charge and charging.

Each valve is equipped with a service port which has a
factory−installed valve stem. Figure 2 provides information
on how to access and operating both angle and ball service
valves.

506650−01

Page 4

Operating Angle Type Service Valve:

1. Remove stem cap with an appropriately sized wrench.

2. Use a service wrench with a hex−head extension (3/16" for liquid line valve sizes and 5/16" for vapor line valve sizes) to back
the stem out counterclockwise as far as it will go.

SERVICE PORT CAP

SERVICE PORT CORE

(VALVE STEM SHOWN

TO INDOOR

UNIT

(VALVE STEM SHOWN OPEN)
INSERT HEX WRENCH HERE

CLOSED) INSERT HEX
WRENCH HERE

SERVICE PORT

CORE

TO OUTDOOR UNIT

ANGLE−TYPE SERVICE VALVE

(BACK−SEATED OPENED)

When service valve is OPEN, the service port is
open to linE set, indoor and outdoor unit.

Operating Ball Type Service Valve:

1. Remove stem cap with an appropriately sized wrench.

2. Use an appropriately sized wrenched to open. To open valve,
rotate stem counterclockwise 90°. To close rotate stem
clockwise 90°.

TO INDOOR UNIT

TO OPEN ROTATE STEM
COUNTERCLOCKWISE 90°.

TO CLOSE ROTATE STEM
CLOCKWISE 90°.

SERVICE PORT

SERVICE PORT

SERVICE PORT

CORE

CAP

TO OUTDOOR

UNIT

BALL (SHOWN
CLOSED)

VALV E
STEM

STEM CAP

STEM CAP

ANGLE−TYPE SERVICE VALVE

(FRONT−SEATED CLOSED)

WHEN SERVICE VALVE IS CLOSED, THE SERVICE PORT IS OPEN
TO

THE LINE SET AND INDOOR UNIT.

To Access Service Port:

A service port cap protects the service port core from contamination and
serves as the primary leak seal.

1. Remove service port cap with an appropriately sized wrench.

2. Connect gauge set to service port.

3. When testing is completed, replace service port cap and tighten as
follows:

 With torque wrench: Finger tighten and

torque cap per table 1.

 Without torque wrench: Finger tighten and

use an appropriately sized wrench to turn
an additional 1/6 turn clockwise.

Reinstall Stem Cap:

Stem cap protects the valve stem from damage and serves as the
primary seal. Replace the stem cap and tighten as follows:

9

10

8

11

12

7

6

 With Torque Wrench: Finger tighten and

then torque cap per table 1.

 Without Torque Wrench: Finger tight-

en and use an appropriately sized
wrench to turn an additional 1/12 turn
clockwise.

9

10

8

11

12

7

6

1/6 TURN

1

2

3

4

5

1/12 TURN

1

2

3

4

5

NOTE  A label with specific torque requirements may be affixed to the stem cap. If the label is present, use the specified torque.

Figure 2. Angle and Ball Service Valves

Page 5

TPA*H4 SERIES

Recovering Refrigerant from Existing System

RECOVERING

REFRIGERANT FROM SYSTEM

DISCONNECT POWER

Disconnect all power to the existing outdoor unit at the service

1

disconnect switch or main fuse box/breaker panel.

SERVICE

DISCONNECT

SWITCH

RECOVERING REFRIGERANT

Remove existing HCFC−22 refrigerant using one of the following procedures:

3

IMPORTANT  Some system configurations may contain higher than normal refrigerant charge due to either large internal coil volumes,

and/or long line sets.

CONNECT MANIFOLD GAUGE SET

Connect a gauge set, clean recovery cylinder and a recovery

2

machine to the service ports of the existing unit. Use the
instructions provided with the recovery machine to make the
connections.

MANIFOLD GAUGES

RECOVERY MACHINE

LOW

CLEAN RECOVERY
CYLINDER

OUTDOOR UNIT

HIGH

METHOD 1:

Us this method if the existing outdoor unit is not equipped with shut−off valves, or if the unit is not operational and you plan to use the existing
HCFC−22 to flush the system.

Remove all HCFC−22 refrigerant from the existing system. Check gauges after shutdown to confirm that the entire system is completely void of
refrigerant.

METHOD 2:

Use this method if the existing outdoor unit is equipped with manual shut−off valves, and you plan to use new HCFC−22 refrigerant to flush the
system.

The following devices could prevent full system charge recovery into the outdoor unit:

 Outdoor unit’s high or low−pressure switches (if applicable) when tripped can cycle the compressor OFF.
 Compressor can stop pumping due to tripped internal pressure relief valve.
 Compressor has internal vacuum protection that is designed to unload the scrolls (compressor stops pumping) when the pressure ratio meets

a certain value or when the suction pressure is as high as 20 psig. (Compressor suction pressures should never be allowed to go into a vacuum.
Prolonged operation at low suction pressures will result in overheating of the scrolls and permanent damage to the scroll tips, drive bearings and
internal seals.)

Once the compressor can not pump down to a lower pressure due to one of the above system conditions, shut off the vapor valve. Turn OFF the
main power to unit and use a recovery machine to recover any refrigerant left in the indoor coil and line set.

Perform the following task:

A Start the existing HCFC−22 system in the cooling mode and close the liquid line valve.
B Use the compressor to pump as much of the existing HCFC−22 refrigerant into the outdoor unit until the outdoor system is full. Turn the outdoor unit

main power OFF and use a recovery machine to remove the remaining refrigerant from the system.

NOTE  It may be necessary to bypass the low pressure switches (if equipped) to ensure complete refrigerant evacuation.

C When the low side system pressures reach 0 psig, close the vapor line valve.

D Check gauges after shutdown to confirm that the valves are not allowing refrigerant to flow back into the low side of the system.

506650−01

Page 6

CLEARANCE ON ALL SIDES  INCHES (MILLIMETERS)

MINIMUM CLEARANCE

ABOVE UNIT

6 (152)

12 (305)

36 (914)

MINIMUM CLEARANCE BETWEEN

DETAIL A

Install unit away
from windows .

DETAIL C

If unit coil cannot be
mounted away from prevail­ing winter winds, a wind bar­rier should be constructed.
Size barrier at least the
same height and width as
outdoor unit. Mount barrier
24 inches (610 mm) from the
sides of the unit in the direc­tion of prevailing winds as il­lustrated.

30 (762)

LINE SET
CONNECTIONS

TWO UNITS

24 (610)

PREVAILING WINTER WINDS

INLET AIR

ACCESS PANEL

NOTES:

 Clearance to one of the other three

 Clearance to one of the remaining

Figure 3. Installation Clearances

Two 90° elbows
installed in line set will
reduce line set vibration.

WIND BARRIER

INLET AIR

INLET AIR

sides must be 36 inches (914mm).

two sides may be 12 inches
(305mm) and the final side may be
6 inches (152mm).

DETAIL B

These units operate under a wide range of weather conditions;
therefore, several factors must be considered when positioning the
outdoor unit. The unit must be positioned to give adequate clearances
for sufficient airflow and servicing.

 Install unit level or, if on a slope, maintain slope tolerance of 2

degrees (or 2 inches per 5 feet [50 mm per 1.5 m]) away from
building structure.

 Install the unit high enough above the ground or roof to allow

adequate drainage of defrost water and prevent ice or snow
build−up.

 In heavy snow areas, do not locate the unit where drifting will

occur. The unit base should be elevated above the depth of
average snows. Stand−off kits are available for ordering using
either catalog numbers  94J45 (4 each) or 30K79 (20 each).

 When installed in areas where low ambient temperatures exist,

locate unit so winter prevailing winds do not blow directly onto
outdoor unit.

 Locate unit away from overhanging roof lines which would allow

water or ice to drop on, or in front of, coil or unto unit.

INLET AIR

MOUNTING SLAB MUST SLOPE

AWAY FROM BUILDING.

STRUCTURE

48 (1219)

DISCHARGE AIR

GROUND LEVEL

Figure 4. Placement, Slab Mounting and Wind Barrier

Page 7

TPA*H4 SERIES

New Unit Placement

See Unit Dimensions on page 2 for sizing mounting slab,
platforms or supports. Refer to figure 3 for mandatory
installation clearance requirements.

CAUTION

In order to avoid injury, take proper precaution when lift­ing heavy objects.

POSITIONING CONSIDERATIONS

Consider the following when positioning the unit:

 Some localities are adopting sound ordinances based

on the unit’s sound level registered from the adjacent
property, not from the installation property. Install the
unit as far as possible from the property line.

If refrigerant lines are routed through a wall, seal and
isolate the opening so vibration is not transmitted to the
building. Pay close attention to line set isolation during
installation of any HVAC system. When properly isolated
from building structures (walls, ceilings. floors), the
refrigerant lines will not create unnecessary vibration and
subsequent sounds.

Also, consider the following when placing and installing a
high−efficiency air conditioner:

REFRIGERANT LINE SET

Field refrigerant piping consists of liquid and suction lines
from the outdoor unit (braze connections) to the indoor unit
coil (flare or braze connections). Use Lennox L15 (braze,
non−flare) series line set, or use field−fabricated refrigerant
lines as listed in table 2.

IMPORTANT

 When possible, do not install the unit directly outside

a window. Glass has a very high level of sound
transmission. For proper placement of unit in relation
to a window see the provided illustration in figure 4.

OUTDOOR UNIT ON SLAB

When installing a unit at grade level, the top of the slab
should be high enough above the grade so that water from
higher ground would not collect around the unit as
illustrated in figure 4.

Slab may be level or have a slope tolerance away from the
building of not more than two degrees, or 2 inches per 5
feet (51 mm per 1524 mm) as illustrated in figure 4.

ROOF MOUNTING

Install the unit at a minimum of 4 inches (102 mm) above
the surface of the roof. Ensure the weight of the unit is
properly distributed over roof joists and rafters. Redwood
or steel supports are recommended. Refer to figure 4,
detail c, for rooftop wind barrier considerations.

NOTICE

Roof Damage!
This system contains both refrigerant and oil. Some

rubber roofing material may absorb oil and cause the
rubber to swell when it comes into contact with oil. The
rubber will then bubble and could cause leaks. Protect
the roof surface to avoid exposure to refrigerant and oil
during service and installation. Failure to follow this
notice could result in damage to roof surface.

New or Replacement Line Set

This section provides information on new installation or
replacement of existing line set. If a new or replacement
line set is not required, then proceed to Brazing
Connections on page 10.

Mineral oils are not compatible with HFC−410A. If oil

must be added, it must be a Polyol ester oil.

The compressor is charged with sufficient Polyol ester oil
for line set lengths up to 50 feet. Recommend adding oil to
system based on the amount of refrigerant charge in the
system. No need to add oil in system with 20 pounds of
refrigerant or less. For systems over 20 pounds − add one
ounce of every five pounds of refrigerant.

Recommended topping−off POE oils are Mobil EAL
ARCTIC 22 CC or ICI EMKARATE RL32CF.

NOTE  When installing refrigerant lines longer than 50
feet, see the Lennox Refrigerant Piping Design and
Fabrication Guidelines, CORP. 9351−L9, or contact
Lennox Technical Support Product Applications for
assistance.

To obtain the correct information from Lennox, be sure to
communicate the following points:

 Model (TPA*H4) and size of unit (e.g. −060).
 Line set diameters for the unit being installed as listed

in table 2 and total length of installation.

 Number of elbows and if there is a rise or drop of the

piping.

MATCHING WITH NEW OR EXISTING INDOOR COIL
AND LINE SET

The RFC1−metering line consisted of a small bore copper
line that ran from condenser to evaporator coil. Refrigerant
was metered into the evaporator by utilizing
temperature/pressure evaporation effects on refrigerant in
the small RFC line. The length and bore of the RFC line
corresponded to the size of cooling unit.

If the TPA*H4 is being used with either a new or existing
indoor coil which is equipped with a liquid line which served
as a metering device (RFCI), the liquid line must be
replaced prior to the installation of the TPA*H4 unit.
Typically a liquid line used to meter flow is 1/4" in diameter
and copper.

506650−01

Page 8

Table 2. Refrigerant Line Set  Inches (mm)

Models

TPA036H4N4
TPA042H4N4
TPA048H4N4

TPA060H4N4 3/8 in. (10 mm) 1−1/8 in. (29 mm) 3/8 in. (10 mm) 1−1/8 in. (29 mm) Field Fabricated

LINE SET

Line Set Isolation  The following illustrations are

examples of proper refrigerant line set isolation:

REFRIGERANT LINE SET  TRANSITION

FROM VERTICAL TO HORIZONTAL

ANCHORED HEAVY NYLON

WIRE TIE OR AUTOMOTIVE

MUFFLER-TYPE HANGER

Field Connections Recommended Line Set

Liquid Line Vapor Line Liquid Line Vapor Line L15 Line Set

3/8 in. (10 mm) 7/8 in (22 mm) 3/8 in. (10 mm) 7/8 in (22 mm) L15−65  15 ft. − 50 ft. (4.6 m − 15 m)

IMPORTANT  Refrigerant lines must not contact structure.

INSTALLATION

NOTE  Similar installation practices should be used if line set is
to be installed on exterior of outside wall.

REFRIGERANT LINE SET  INSTALLING

VERTICAL RUNS (NEW CONSTRUCTION SHOWN)

NOTE  Insulate liquid line when it is routed through areas where the
surrounding ambient temperature could become higher than the
temperature of the liquid line or when pressure drop is equal to or greater
than 20 psig.

AUTOMOTIVE

MUFFLER-TYPE HANGER

IMPORTANT  Refrigerant lines must not contact wall

WALL
STUD

STRAP LIQUID LINE TO
VAPOR LINE

LIQUID LINE

NON−CORROSIVE

METAL SLEEVE

VAPOR LINE − WRAPPED
IN ARMAFLEX

REFRIGERANT LINE SET  INSTALLING

HORIZONTAL RUNS

To hang line set from joist or rafter, use either metal strapping material
or anchored heavy nylon wire ties.

WIRE TIE (AROUND
VAPOR LINE ONLY)

8 FEET (2.43 METERS)

STRAPPING

MATERIAL (AROUND

VAPOR LINE ONLY)

FLOOR JOIST OR

ROOF RAFTER

TAPE OR
WIRE TIE

FLOOR JOIST OR

ROOF RAFTER

8 FEET (2.43 METERS)

NON−CORROSIVE
METAL SLEEVE

STRAP THE VAPOR LINE TO THE JOIST
OR RAFTER AT 8 FEET (2.43 METERS)
INTERVALS THEN STRAP THE LIQUID
LINE TO THE VAPOR LINE.

TAPE OR
WIRE TIE

OUTSIDE WALL

WOOD BLOCK

BETWEEN STUDS

VAPOR LINE WRAPPED

WITH ARMAFLEX

OUTSIDE

WALL

PVC

PIPE

FIBERGLASS

INSULATION

VAPOR LINE

SLEEVE

CAULK

LIQUID
LINE

LIQUID LINE

WIRE TIE

INSIDE WALL

STRAP

NON−CORROSIVE
METAL SLEEVE

WIRE TIE

WOOD BLOCK

WIRE TIE

STRAP

WARNING  Polyol ester (POE) oils used with HFC−410A
refrigerant absorb moisture very quickly. It is very important that the

refrigerant system be kept closed as much as possible. DO NOT
remove line set caps or service valve stub caps until you are ready
to make connections.

Figure 5. Line Set Installation

Page 9

TPA*H4 SERIES

IMPORTANT

Polyol ester (POE) oils used with HFC−410A
refrigerant absorb moisture very quickly. It is very
important that the refrigerant system be kept closed
as much as possible. DO NOT remove line set caps
or service valve stub caps until you are ready to make
connections.

IMPORTANT

If this unit is being matched with an approved line set
or indoor unit coil which was previously charged with
mineral oil, or if it is being matched with a coil which
was manufactured before January of 1999, the coil
and line set must be flushed prior to installation. Take
care to empty all existing traps. Polyol ester (POE) oils
are used in Lennox units charged with HFC−410A
refrigerant. Residual mineral oil can act as an
insulator, preventing proper heat transfer. It can also
clog the expansion device, and reduce the system
performance and capacity.
Failure to properly flush the system per the
instructions below will void the warranty.

Brazing Connections

Use the procedures outline in figures 6 and 7 for brazing
line set connections to service valves.

CAUTION

Brazing alloys and flux contain materials which are
hazardous to your health.

Avoid breathing vapors or fumes from brazing
operations. Perform operations only in well−ventilated
areas.

Wear gloves and protective goggles or face shield to
protect against burns.

Wash hands with soap and water after handling brazing
alloys and flux.

IMPORTANT

Connect gauge set low pressure side to vapor line
service valve and repeat procedure starting at
paragraph 4 for brazing the liquid line to service port
valve.

IMPORTANT

Allow braze joint to cool before removing the wet rag
from the service valve. Temperatures above 250ºF can
damage valve seals.

IMPORTANT

WARNING

Danger of fire. Bleeding the refrigerant
charge from only the high side may result
in pressurization of the low side shell and
suction tubing. Application of a brazing
torch to a pressurized system may result
in ignition of the refrigerant and oil
mixture − Check the high and low
pressures before applying heat.

WARNING

When using a high pressure gas such as
dry nitrogen to pressurize a refrigeration
or air conditioning system, use a
regulator that can control the pressure
down to 1 or 2 psig (6.9 to 13.8 kPa).

Use silver alloy brazing rods with 5% minimum silver
alloy for copper−to−copper brazing. Use 45% minimum
alloy for copper−to−brass and copper−to−steel brazing.

WARNING

Fire, Explosion and Personal Safety
Hazard.

Failure to follow this warning could
result in damage, personal injury or
death.

Never use oxygen to pressurize or
purge refrigeration lines. Oxygen,
when exposed to a spark or open
flame, can cause fire and/or an ex­plosion, that could result in property
damage, personal injury or death.

506650−01

Page 10

CUT AND DEBUR

Cut ends of the refrigerant lines square (free from nicks or dents)

1

and debur the ends. The pipe must remain round. Do not crimp end
of the line.

CUT AND DEBUR

LINE SET SIZE MATCHES

SERVICE VALVE CONNECTION

SERVICE VALVE

COPPER TUBE

REDUCER

CONNECTION

STUB

LINE SET SIZE IS SMALLER

THAN CONNECTION

REFRIGERANT LINE

DO NOT CRIMP SERVICE VALVE

CONNECTOR WHEN PIPE IS

SMALLER THAN CONNECTION

CAP AND CORE REMOVAL

Remove service cap and core from both the

2

vapor and liquid line service ports.

SERVICE PORT

CAP

SERVICE

PORT
CORE

LIQUID LINE SERVICE

VALV E

SUCTION / VAPOR LINE

SERVICE VALVE

ATTACH THE MANIFOLD GAUGE SET FOR BRAZING LIQUID AND SUCTION / VAPOR LINE SERVICE
VALVES

3

Flow regulated nitrogen (at 1 to 2 psig) through the low−side refrigeration gauge set into the liquid line service port valve, and out of the suction /
vapor line service port valve.

A Connect gauge set low pressure side to

liquid line service valve (service port).

B Connect gauge set center port to bottle of

nitrogen with regulator.

C Remove Schrader valve in suction / vapor

line service port to allow nitrogen to escape.

ATTACH

GAUGES

HIGHLOW

USE REGULATOR TO FLOW

NITROGEN AT 1 TO 2 PSIG.

SERVICE

PORT
CORE

SERVICE
PORT CAP

SUCTION / VAPOR SERVICE PORT MUST BE

OPEN TO ALLOW EXIT POINT FOR NITROGEN

VAPOR LINE

INDOOR

UNIT

LIQUID LINE

C

LIQUID LINE SERVICE

SUCTION /

VAPOR LINE

SERVICE

VALV E

VALV E

B

WHEN BRAZING LINE SET TO

A

SERVICE VALVES, POINT FLAME

AWAY FROM SERVICE VALVE.

Figure 6. Brazing Procedures

OUTDOOR

UNIT

NITROGEN

Page 11

TPA*H4 SERIES

WRAP SERVICE VALVES

To help protect service valve seals during brazing, wrap a saturated cloth around service valve bodies and copper tube stub. Use another

4

saturated cloth underneath the valve body to protect the base paint.

FLOW NITROGEN

Flow regulated nitrogen (at 1 to 2 psig) through the refrigeration gauge set into the valve stem port connection on the liquid service valve and

5

out of the suction / vapor valve stem port. See steps 3A, 3B and 3C on manifold gauge set connections

BRAZE LINE SET

Wrap both service valves with a saturated cloth as illustrated here before brazing to line set.

6

LIQUID LINE SERVICE VALVE

WHEN BRAZING LINE SET TO

SERVICE VALVES, POINT FLAME

AWAY FROM SERVICE VALVE.

IMPORTANT  Allow braze joint to cool. Apply

additional saturated cloths to help cool brazed joint.
Do not remove wet rag until piping has cooled.
Temperatures above 250ºF will damage valve seals.

LIQUID LINE

SATURATED CLOTH

WARNING

1. FIRE, PERSONAL INJURY, OR PROPERTY
DAMAGE will result if you do not wrap a wet cloth

around both liquid and suction line service valve
bodies and copper tube stub while brazing in the line
set! The braze, when complete, must be quenched
with water to absorb any residual heat.

2. Do not open service valves until refrigerant lines and
indoor coil have been leak−tested and evacuated.
Refer to procedures provided in this supplement.

SUCTION / VAPOR LINE

PREPARATION FOR NEXT STEP

7

After all connections have been brazed, disconnect manifold gauge set from service ports. Apply saturated rags to both services valves to cool
piping. Once piping is cool, remove all wet cloths. Refer to the unit installation instructions for the next step in preparing the unit.

SUCTION / VAPOR LINE

SERVICE VALVE

SATURATED CLOTH

WHEN BRAZING LINE SET TO

SERVICE VALVES, POINT FLAME

AWAY FROM SERVICE VALVE.

Figure 7. Brazing Procedures (continued)

506650−01

Page 12