Lennox 13HPD−018, 13HPD−036, 13HPD−024, 13HPD−030, 13HPD−042 Installation Instructions Manual

INSTALLATION

2007 Lennox Industries Inc.

Dallas, Texas, USA

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

WARNING

Improper installation, adjustment, alteration,
service or maintenance can cause property damage,
personal injury or loss of life. Installation and
service must be performed by a qualified installer or
service agency.

CAUTION

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.

INSTRUCTIONS

Merit® Series13HPD Units

1−½ to 5 TONS

HEAT PUMP UNITS

505,361M
09/07
Supersedes 504,943M

Table of Contents

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

13HPD Outdoor Unit 1. . . . . . . . . . . . . . . . . . . . . . . . . . .

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

General Information 2. . . . . . . . . . . . . . . . . . . . . . . . . . .

Recovering Refrigerant from Existing System 4. . . . .

Disconnecting and Removing Old Outdoor Unit 5. . . .

Positioning New Outdoor Unit 5. . . . . . . . . . . . . . . . . . .

New or Replacement Refrigerant Line Set 6. . . . . . . .

Replacing Refrigerant Metering Device 8. . . . . . . . . . .

Brazing Connections 9. . . . . . . . . . . . . . . . . . . . . . . . . . .

Testing for Leaks 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Evacuating the System 11. . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Connections 12. . . . . . . . . . . . . . . . . . . . . . . . .

Start−Up Procedures 14. . . . . . . . . . . . . . . . . . . . . . . . . . .

Determining Charge Method 15. . . . . . . . . . . . . . . . . . . .

System Operation 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Defrost System 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maintenance 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Homeowner Information 20. . . . . . . . . . . . . . . . . . . . . . . .

Start−Up and Performance Checklist 22. . . . . . . . . . . . .

Shipping and Packing List

1 − Assembled 13HPD outdoor unit

Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.

Litho U.S.A.

IMPORTANT

The Clean Air Act of 1990 bans the intentional
venting of refrigerant (CFCs, HCFCs AND HFCs) as
of July 1, 1992. Approved methods of recovery,
recycling or reclaiming must be followed. Fines
and/or incarceration may be levied for
noncompliance.

09/07 505,361M

*2P0907* *P505361M*

13HPD Outdoor Unit

The Lennox 13HPD Heat Pumps, which will also be
referred to in this instruction as the outdoor unit, uses
HCFC−22 refrigerant. This unit must be installed with a
matching indoor unit and line set as outlined in the Lennox
Engineering Handbook. This unit is designed for use in
check thermal expansion valve (CTXV) and fixed orifice
systems.

Page 1

Unit Dimensions − inches (mm)

A

B

SIDE VIEW

Model Number A B

13HPD−018 24−1/4 (616) 33−1/4 (845)
13HPD−024 24−1/4 (616) 33−1/4 (845)
13HPD−030 24−1/4 (616) 29−1/4 (743)
13HPD−036 24−1/4 (616) 33−1/4 (845)
13HPD−042 28−1/4 (616) 33−1/4 (845)
13HPD−048 28-1/4 (718) 37 (940)
13HPD−060 32-1/4 (819) 37 (940)

WARNING

This product and/or the indoor unit it is matched
with may contain fiberglass wool.

Disturbing the insulation during installation,
maintenance, or repair will expose you to fiberglass
wool dust. Breathing this may cause lung cancer.
(Fiberglass wool is known to the State of California
to cause cancer.)

Fiberglass wool may also cause respiratory, skin,
and eye irritation.

To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact
your supervisor.

Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379−9900

A

Outdoor Coil Fan

Compressor

Vapor and Liquid

Line Connections

Optional Unit Stand-off Kit
(4) (Field−installed)

Discharge Air

SIDE VIEW

General Information

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation. When servicing or
repairing HVAC components, ensure caps and fasteners
are appropriately tightened. Table 1 lists torque values for
typical service and repair items.

Table 1. Torque Requirements

Part 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 SETS

When checking the system charge, use a manifold gauge
set that features low−loss anti−blow back fittings. See figure
1 for a typical manifold gauge connection setup.

OPERATING SERVICE VALVES

The liquid and vapor lines service valves are typically 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.

505361M 09/07

Page 2

DISTRIBUTOR

CHECK

EXPANSION VALVE

BI−FLOW

LOW

PRESSURE

GAUGE MANIFOLD

PRESSURE

TO

HCFC−22

DRUM

HIGH

LIQUID
LINE
VALV E

FILTER /
DRIER

LIQUID

SERVICE

PORT

OUTDOOR

COIL

MUFFLER

COMPRESSOR

Figure 1. Typical Manifold Gauge Connection Setup

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.

1/6 TURN

12

11

10

9

8

7

This illustrates how to use an appropriately sized wrench to tighten
caps an additional 1/6 or 1/12 turn clockwise.

1

2

3

4

5

6

11

10

9

8

1/12 TURN

12

1

2

3

4

7

5

6

Figure 2. Cap Tightening Distances

IMPORTANT

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

Operating Angle−Type Service Valve

To Access Angle−Type Service Port:

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

OUTDOOR UNIT

REVERSING VALVE

VAPOR
SERVICE
PORT

SERVICE PORT CAP

SERVICE PORT

CLOSED TO BOTH

INDOOR AND

OUTDOOR UNITS]

VALVE STEM

FRONT-SEATED

TO INDOOR

UNIT

TO OUTDOOR UNIT

VAPOR LINE
VALV E

CHECK EXPANSION VALVE OR

FIXED ORIFICE DEVICE

CORE

NOTE − Arrow indicate direction
of refrigerant flow.

INDOOR UNIT

INDOOR

COIL

SERVICE PORT

(VALVE STEM SHOWN
CLOSED) INSERT HEX
WRENCH HERE

STEM CAP

Figure 3. Angle−Type Service Valve

(Valve Font−Seated Closed)

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

2. Connect gauge to the service port.

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

 With Torque Wrench: Finger tighten and then

tighten per table 1.

 Without Torque Wrench: Finger tighten and use an

appropriately sized wrench to turn an additional
1/6 turn clockwise as illustrated in figure 2.

To Open and Close Angle−Type Service Valve:

A valve stem cap protects the valve stem from
contamination and assures a leak−free seal.

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.

Page 3

13HPD SERIES

3. Replace the stem cap and tighten as follows:

 With Torque Wrench: Tighten finger tight and then

tighten per table 1.

 Without Torque Wrench: Finger tighten and use an

appropriately sized wrench to turn an additional
1/12 turn clockwise as illustrated in figure 2.

SERVICE PORT CAP

SERVICE PORT

CORE

OPEN TO BOTH

INDOOR AND

OUTDOOR UNITS]

TO INDOOR

UNIT

TO OUTDOOR

UNIT

STEM CAP

SERVICE PORT

(VALVE STEM SHOWN OPEN)
INSERT HEX WRENCH HERE

 With Torque Wrench: Finger tighten and then

tighten per table 1.

 Without Torque Wrench: Finger tighten and use an

appropriately sized wrench to turn an additional
1/12 turn clockwise as illustrated in figure 2.

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

NOTE− To prevent stripping of the cap, the wrench should
be appropriately sized and fit snugly over the cap before
tightening the cap.

Open to line set when valve is closed, to
both line set and unit when valve is open.

Use appropriately sized
wrench.

To open rotate stem
counterclockwise 90°.

To close rotate stem clockwise
90°.

TO INDOOR UNIT

VALV E
STEM

BALL
(SHOWN
CLOSED)

Figure 4. Angle−Type Service Valve

(Valve Back−Seated Opened)

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

Operating Ball−Type Service Valve

To Access Ball−Type 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 to the service port.

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

 With Torque Wrench: Finger tighten and then

tighten per table table 1.

 Without Torque Wrench: Finger tighten and use an

appropriately sized wrench to turn an additional
1/6 turn clockwise as illustrated in figure 2.

To Open and Close Ball−Type Service Valve:

A valve stem cap protects the valve stem from
contamination and assures a leak−free seal.

1. Remove stem cap with a wrench.

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

3. Replace the stem cap and tighten as follows:

SERVICE PORT

SERVICE PORT

CORE

SERVICE PORT CAP

STEM CAP

TO OUTDOOR UNIT

Figure 5. Ball−Type Service Valve

Recovering Refrigerant from Existing
HCFC−22 System

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

METHOD 1:

If the existing outdoor unit is not equipped with shut−off
valves, or if the unit is not operational, then:

1. Disconnect all power to the existing outdoor unit.

2. Connect to the existing unit a gauge set, clean
recovery cylinder and a recovery machine. Use the
instructions provided with the recover machine on how
to setup the connections.

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

4. Disconnect the liquid and vapor lines from the existing
outdoor unit.

5. Remove the existing outdoor unit.

NOTE − Use recovery machine instructions for specific
setup requirements.

505361M 09/07

Page 4

RECOVERY MACHINE

MANIFOLD GAUGES

(SEE NOTES

BELOW FIGURE)

CLEAN RECOVERY CYLINDER

OUTDOOR UNIT

Figure 6. Typical Refrigerant Recovery (Method 1)

METHOD 2:

If the existing outdoor unit is equipped with manual shut−off
valves then:

1. Start the existing HCFC−22 system in the cooling
mode and close the liquid line valve.

2. Pump all of the existing HCFC−22 refrigerant back into
the outdoor unit.

NOTE − It may be necessary to bypass the low pressure
switches to ensure complete refrigerant evacuation.

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

4. Disconnect all power to the existing outdoor unit.
Check gauges after shutdown to confirm that the
valves are not allowing refrigerant to flow back into the
low side of the system.

5. Disconnect the liquid and vapor lines from the existing
outdoor unit.

Disconnecting and Removing Old
Outdoor Unit

Perform the following task at the existing outdoor unit:

 Disconnect line set at the service valves.
 Disconnect electrical service at the disconnect switch.
 Remove old outdoor unit.

(SEE NOTES

BELOW

FIGURE)

SEE NOTES NOTES

BELOW FIGURE)

(SEE NOTES

BELOW

FIGURE)

Figure 7. Installation Clearances

NOTES:

 Service clearance of 30 in. (762 mm) must be

maintained on one of the sides adjacent to the control
box.

 Clearance to one of the other three sides must be 36

in. (914 mm)

 Clearance to one of the remaining two sides may be

12 in. (305 mm) and the final side may be 6 in. (152
mm)

 48 in. (1219 mm) clearance required on top of unit.
 A clearance of 24 in. (610 mm) must be maintained

between two units

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.

 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 8.

INSTALL UNIT AWAY

FROM WINDOWS

Positioning New Outdoor Unit

CAUTION

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

See Unit Dimensions on page 2 to determine the correct
mounting size slab, platform or support. Refer to figure 7
for mandatory installation clearance requirements

Page 5

TWO 90° ELBOWS INSTALLED IN LINE SET

WILL REDUCE LINE SET VIBRATION.

Figure 8. Outside Unit Placement

13HPD SERIES

PLACING OUTDOOR UNIT ON SLAB

Slab may be level or have a slope tolerance away from the
building of not more than two degrees, or two inches per
five feet (51 mm per 1524 mm).

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 9.

BUILDING

STRUCTURE

DISCHARGE AIR

MOUNTING

SLAB

GROUND LEVEL

Figure 9. Ground Level Slab Mounting

INSTALLING OUTDOOR UNIT ON ROOF

Install the unit a minimum of six inches (152 mm) above the
roof surface to avoid ice build−up around the unit. Locate
the unit above a load bearing wall or area of the roof that
can adequately support the unit. Consult local codes for
rooftop applications.

If unit coil cannot be mounted away from prevailing winter
winds, a wind barrier should be constructed as illustrated in
figure 10. 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.

Prevailing Winter Winds

wind barrier

inlet air

inlet air

inlet air

inlet air

Figure 10. Rooftop Application and Wind Barrier

New or Replacement Refrigerant 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 9.

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.

REFRIGERANT LINE SET

Field refrigerant piping consists of liquid and vapor 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.

Table 2. Refrigerant Line Set

Field

Model

−018

−024

−030

−036

−042

−048

−060

Connections

Liquid
Line

3/8 in.
(10 mm)

3/8 in.
(10 mm)

3/8 in.
(10 mm)

Vapor
Line

3/4 in
(19 mm)

7/8 in
(22 mm)

1−1/8 in.
(29 mm)

NOTE − When installing refrigerant lines longer than 50
feet, contact Lennox Technical Support Product
Applications for assistance or Lennox piping manual. To
obtain the correct information from Lennox, be sure to
communicate the following points:

 Model (13HPD) 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 13HPD 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 13HPD unit.
Typically a liquid line used to meter flow is 1/4" in diameter
and copper.

Recommended Line Set

Liquid
Line

3/8 in.
(10
mm)

3/8 in.
(10
mm)

3/8 in.
(10
mm)

Vapor
Line

3/4 in
(19 mm)

7/8 in
(22 mm)

1−1/8 in.
(29 mm)

L15
Line Sets

L15−41
15 ft. − 50 ft.
(4.6 m − 15 m)

L15−65
15 ft. − 50 ft.
(4.6 m − 15 m)

Field
Fabricated

505361M 09/07

Page 6

INSTALLING LINE SET
Line Set IsolationThis reference illustrates

procedures, which ensure proper refrigerant line set
isolation:

Line set for heat pump applications can not be installed
underground. For more information see the Lennox
Refrigerant Piping Design and Fabrication Guidelines, or
contact Lennox Technical Support Product Applications
for assistance.

 Installation of line set on vertical runs is illustrated in

figure 11.

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

ANCHORED HEAVY

NYLON WIRE TIE

WALL
STUD

 Installation of a transition from horizontal to

vertical is illustrated in figure 12.

 Installation of line set on horizontal runs is

illustrated in figure 13.

OUTSIDE WALL

WOOD BLOCK

BETWEEN STUDS

VAPOR LINE WRAPPED

IMPORTANT!

REFRIGERANT

LINES MUST NOT

CONTACT

STRUCTURE.

WITH ARMAFLEX

OUTSIDE

WALL

VAPOR LINE

LIQUID LINE

LIQUID LINE

WIRE TIE

INSIDE WALL

STRAP

SLEEVE

WIRE TIE

WOOD BLOCK

WIRE TIE

STRAP

SLEEVE

STRAP LIQUID LINE

TO VAPOR LINE

LIQUID LINE

METAL SLEEVE

AUTOMOTIVE

MUFFLER-TYPE HANGER

WALL

STUD

METAL SLEEVE

VAPOR LINE − WRAPPED

IN ARMAFLEX

VAPOR LINE WRAPPED

IN ARMAFLEX

STRAP LIQUID LINE

TO VAPOR LINE

LIQUID

LINE

Figure 12. Refrigerant Line Set: Transition from

Vertical to Horizontal

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

STRAPPING MATERIAL
(AROUND VAPOR LINE

ONLY)

FLOOR JOIST OR

ROOF RAFTER

8 FEET

8 FEET

WIRE TIE
(AROUND

VAPOR LINE

TAPE OR

WIRE TIE

ONLY)

CAULK

PVC

PIPE

FIBERGLASS

INSULATION

IMPORTANT - REFRIGERANT LINES MUST

NOT CONTACT WALL.

Figure 11. Refrigerant Line Set: Installing Vertical

Runs (New Construction Shown)

Page 7

TAPE OR
WIRE TIE

FLOOR JOIST OR

ROOF RAFTER

METAL

SLEEVE

Strap the vapor line to the
joist or rafter at 8 feet
intervals then strap the
liquid line to the vapor line.

Figure 13. Refrigerant Line Set: Installing Horizontal

Runs

13HPD SERIES

Replacing Refrigerant Metering Device

13HPD units are used in check thermal expansion valve
(CTXV) and fixed orifice systems. See the indoor unit
installation instruction and the Lennox Engineering
Handbook for approved metering device and application
information. Table 2 lists liquid and vapor connection
sizes, line sizes and corresponding line set.

Remove the existing HCFC−22 fixed orifice device or
CTXV from the indoor coil if required. See figure 14 for
disassembly and typical removal instructions.

The CTXV can be installed internal or external to the indoor
coil. In applications where an uncased coil is being
installed in a field provided plenum, install the CTXV in a
location that will provide easy access for field servicing.
Refer to Figure 15 for reference during installation of
CTXV.

(Uncased Coil Shown)

TWO PIECE PATCH

PLATE(UNCASED

COIL ONLY)

DISTRIBUTOR
TUBES

ORIFICE
HOUSING

EQUALIZER
LINE

O−RING

ORIFICE

OR

EXPANSION VALVE

(SEE NOTE)

O−RING

STRAINER

SENSING
LINE

See table 3 for the fixed orifice size for each unit. In
non−standard applications, the provided fixed orifice may
not be appropriate.

CTXV SYSTEMS

1. On fully cased coils, remove the coil access and
plumbing panels.

2. Remove any shipping clamps holding the liquid line
and distributor assembly.

3. Using two wrenches, disconnect liquid line from
distributor. Take care not to twist or damage distributor
tubes during this process.

NOTE − If necessary, remove existing flow control device
(fixed orifice or expansion valve) from existing line set
before installing approved metering device.

4. Remove and discard RFC orifice and Teflon washer.

5. Remove and discard cap from the equalizer line port
on the vapor line. Check for valve core in port fitting
and if installed, remove from port.

6. Install one of the provided Teflon washers around the
stubbed end of the CTXV.

7. Attach the stubbed end of the kit valve to the distributor
assembly.

8. Place the remaining Teflon washer around the other
end of the CTXV.

9. Attach the liquid line to the CTXV.

10. Attach the sensing bulb of the CTXV in the proper
orientation as illustrated in figure 15 to the vapor line
using the clamp an screws provided with the CTXV.

REMOVE AND DISCARD

SEAL ASSEMBLY (IF

APPLICABLE)

ACCESS FITTING

(NO VALVE CORE)

Sensing bulb (insulation
required, if mounted
external to the coil casing.

VAPOR

LINE

LIQUID
LINE

Figure 14. Typical Metering Device Installation

FIXED ORIFICE SYSTEMS

Replace the existing indoor unit fixed orifice with the orifice
supplied with the outdoor unit. Place the supplied fixed
orifice sticker on the indoor cabinet after installation.

Table 3. Fixed Orifice Part Numbers

HCFC−22

Model

018 100484−08 (0.057)
024 100484−11 (0.061)
030 100484−21 (0.072)

036 100484−23 (0.074)
042 100484−30 (0.082)

037 and 048 Not Supported

060 100484−44 (0.098)

505361M 09/07

13HPD

Vapor Line

Vapor Line

Bulb

Bulb

NOTE − Never mount on bottom of line.

12

12

On lines smaller than
7/8", mount sensing bulb
at either the 3 or 9 o’clock
position.

Bulb

On 7/8" and larger lines,
mount sensing bulb at
either the 4 or 8 o’clock
position. Never mount
on bottom of line.

Bulb

Figure 15. CTXV Sensing Bulb Installation

NOTE − Insulating the sensing bulb once installed may be
required when the bulb location is external to the coil
casing.

11. Connect the equalizer line port from the CTXV to the
equalizer port on the vapor line.

12. To prevent any possibility of water damage, properly
insulate all parts of the CTXV assembly that may
sweat due to its surrounding ambient

Page 8

NOTE − The CTXV can be installed internally in coil
blowers, or external or internal to indoor coil only
applications.

Table 4. CTXV Indoor Kits

Model Kit Number

13HPD−018, −024, −030, −036 LB−85759F

13HPD−042, −048 LB−85759G

13HPD−060 100188−01

IMPORTANT

Failure to remove a fixed orifice when installing an
expansion valve on the indoor coil will result in
improper operation and damage to the system.

Brazing Connections

OUTDOOR UNIT

SERVICE VALVE

REMOVE SERVICE

PORT CAP

REMOVE PORT CORE

Figure 16. Typical Service Valve Port Core Removal

WARNING

Danger of fire. Bleeding the
refrigerant charge from only the high
side may result in the low side shell
and suction tubing being
pressurized. Application of a brazing
torch while pressurized may result in
ignition of the refrigerant and oil
mixture − check the high and low
pressures before unbrazing.

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.

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 the following procedure to braze the line set to the new
outdoor unit. Figure 17 is provided as a general guide for
preparing to braze the line set to the outdoor unit.

Before brazing the line set, remove the service port core
from both of the outdoor unit’s service valves as illustrated
in figure 16.

1. Cut ends of the refrigerant lines square (free from
nicks or dents). Debur the ends. The pipe must remain
round, do not pinch end of the line.

2. Remove service cap and core from both the vapor and
liquid line service ports.

3. Connect gauge low pressure side to liquid line service
valve.

4. To protect components during brazing, wrap a wet
cloth around the liquid line service valve body and
copper tube stub and use another wet cloth
underneath the valve body to protect the base paint.

5. Flow regulated nitrogen (at 1 to 2 psig) through the
refrigeration gauge set into the valve stem port
connection on the liquid line service valve and out of
the valve stem port connection on the vapor service
valve. The CTXV metering device at the indoor unit
coil will allow low pressure nitrogen to flow through the
system.)

NOTE − The TXV metering device at the indoor unit coil will
allow low pressure nitrogen to flow through the system.)

NOTE − Use silver alloy brazing rods with five or six percent
minimum silver alloy for copper−to−copper brazing or 45
percent silver alloy for copper−to−brass or copper−to−steel
brazing.

Page 9

13HPD SERIES

1

2

3

CUT AND DEBUR

INDOOR UNIT COIL

REMOVE CAP AND CORE FROM

BOTH SERVICE PORTS

VAPOR LINE

LIQUID LINE

6

5

BRAZE LINE SET

Figure 17. Brazing Connections

6. Braze the line to the liquid line service valve. Turn off
nitrogen flow. Repeat procedure starting with
paragraph 4 for brazing the vapor line to vapor service
valve.

After all connections have been brazed, disconnect
manifold gauge set the from service ports and remove
wrapping. Reinstall the service port core for both of the
outdoor unit’s service valves as illustrated in figure 18.

OUTDOOR UNIT

LIQUID AND VAPOR

SERVICE VALVES

DO NOT INSTALL

CAPS AT THIS TIME

ATTACH

GAUGES

SERVICE

VALVE

13HPD

UNIT

SERVICE

VALVE

FLOW NITROGEN

NITROGEN

4

WRAP SERVICE

VALV E

NOTE − Normally, the high pressure hose is connected to
the liquid line port; however, connecting it to the vapor port
better protects the manifold gauge set from high pressure
damage.

WARNING

Refrigerant can be harmful if it is inhaled.
Refrigerant must be used and recovered
responsibly.

Failure to follow this warning may result in personal
injury or death.

INSTALL SERVICE

PORT CORES

Figure 18. Typical Service Valve Port Core

Installation

Testing for Leaks

After the line set has been connected to both the indoor
and outdoor units, check the line set connections at both
the indoor and outdoor units unit for leaks. Use the
following procedure to test for leaks:

IMPORTANT

Leak detector must be capable of sensing HFC
refrigerant.

1. Connect an HCFC−22 manifold gauge set high
pressure hose to the vapor valve service port.

505361M 09/07

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 damage by fire and/
or an explosion, that could result in
personal injury or death.

2. With both manifold valves closed, connect the cylinder
of HCFC−22 refrigerant to the center port of the
manifold gauge set. Open the valve on the HCFC−22
cylinder (vapor only).

3. Open the high pressure side of the manifold to allow
HCFC−22 into the line set and indoor unit.

4. Weigh in a trace amount of HCFC−22. [A trace amount

is a maximum of two ounces (57 g) refrigerant or three
pounds (31 kPa) pressure].

Page 10

5. Close the valve on the HCFC−22 cylinder and the valve
on the high pressure side of the manifold gauge set.

6. Disconnect the HCFC−22 cylinder.

7. Connect a cylinder of dry nitrogen with a pressure
regulating valve to the center port of the manifold
gauge set.

NOTE − Amounts of refrigerant will vary with line lengths.

8. Adjust dry nitrogen pressure to 150 psig (1034 kPa).

9. Open the valve on the high side of the manifold gauge
set in order to pressurize the line set and the indoor unit.

10. After a few minutes, open one of the service valve
ports and verify that the refrigerant added to the
system earlier is measurable with a leak detector.

11. Check the indoor and outdoor units and line set for
leaks using the leak detector mentioned in paragraph

10.

12. Proceed with evacuation as outlined in the Evacuating
the System.

Evacuating the System

WARNING

Danger of Equipment Damage. Avoid deep
vacuum operation. Do not use compressors to
evacuate a system. Extremely low vacuums can
cause internal arcing and compressor failure.
Damage caused by deep vacuum operation will
void warranty.

IMPORTANT

Use a thermocouple or thermistor electronic vacuum
gauge that is calibrated in microns. Use an instrument
capable of accurately measuring down to 50 microns.

Evacuating the system of non−condensables is critical for
proper operation of the unit. Non−condensables are
defined as any gas that will not condense under
temperatures and pressures present during operation of
an air conditioning system. Non−condensables and water
vapor combine with refrigerant to produce substances that
corrode copper piping and compressor parts.

1. Connect manifold gauge set to the service valve ports
as follows:

 low pressure gauge to vapor line service valve
 high pressure gauge to liquid line service valve

2. Connect micron gauge.

3. Connect the vacuum pump (with vacuum gauge) to
the center port of the manifold gauge set.

4. Open both manifold valves and start the vacuum
pump.

5. Evacuate the line set and indoor unit to an absolute
pressure of 23,000 microns (29.01 inches of
mercury).

NOTE − During the early stages of evacuation, it is
desirable to close the manifold gauge valve at least once to
determine if there is a rapid rise in sure indicates a
relatively large leak. If this occurs, repeat the leak testing
procedure.

NOTE − The term absolute pressure means the total
actual pressure within a given volume or system, above
the absolute zero of pressure. Absolute pressure in a
vacuum is equal to atmospheric pressure minus vacuum
pressure.

6. When the absolute pressure reaches 23,000 microns
(29.01 inches of mercury), close the manifold gauge
valves, turn off the vacuum pump and disconnect the
manifold gauge center port hose from vacuum pump.
Attach the manifold center port hose to a dry nitrogen
cylinder with pressure regulator set to 150 psig (1034
kPa) and purge the hose. Open the manifold gauge
valves to break the vacuum in the line set and indoor
unit. Close the manifold gauge valves.

7. Shut off the dry nitrogen cylinder and remove the
manifold gauge hose from the cylinder. Open the
manifold gauge valves to release the dry nitrogen from
the line set and indoor unit.

8. Reconnect the manifold gauge to the vacuum pump,
turn the pump on, and continue to evacuate the line set
and indoor unit until the absolute pressure does not
rise above 500 microns (29.9 inches of mercury) within
a 20−minute period after shutting off the vacuum pump
and closing the manifold gauge valves.

9. When the absolute pressure requirement above has
been met, disconnect the manifold hose from the
vacuum pump and connect it to an upright cylinder of
HCFC−22 refrigerant. Open the manifold gauge valve
1 to 2 psig in order to release the vacuum in the line set
and indoor unit.

10. Close manifold gauge valves and shut off the
HCFC−22 cylinder and remove the manifold gauge
set.

SERVICING UNITS DELIVERED VOID OF CHARGE

If the system is void of refrigerant, clean the system using
the procedure described below.

1. Use nitrogen to pressurize the system and check for
leaks. Repair all leaks.

2. Evacuate the system to remove as much of the
moisture as possible.

3. Use nitrogen to break the vacuum and install a new
filter drier in the system.

4. Evacuate the system again. Then, weigh the
appropriate amount of HCFC−22 refrigerant as listed
on unit nameplate into the system.

5. Monitor the system to determine the amount of
moisture remaining in the oil. It may be necessary to
replace the filter drier several times to achieve the
required dryness level. If system dryness is not

verified, the compressor will fail in the future.

Page 11

13HPD SERIES

Electrical Connections

NOTE − 24VAC, Class II circuit connections are made in
the low voltage junction box

NOTE − Units are approved for use only with copper
conductors.

NOTE − A complete unit wiring diagram is located inside
the unit control box cover.

NOTE − To facilitate conduit, a hole is in the bottom of the
control box. Connect conduit to the control box using a
proper conduit fitting.

Refer to the indoor unit installation instruction for additional
wiring application diagrams and refer to unit nameplate for
minimum circuit ampacity and maximum overcurrent
protection size. Figures 21 and 22 illustrate typical outdoor
unit wiring diagrams for the 13HPD series heat pumps.

 In the U.S.A., wiring must conform with current local

codes and the current National Electric Code (NEC).

 In Canada, wiring must conform with current local codes

and the current Canadian Electrical Code (CEC).

WARNING

Electric Shock Hazard. Can cause
injury or death.

Line voltage is present at all
components on units with single-pole
contactors, even when unit is not in
operation!

Unit may have multiple power
supplies. Disconnect all remote
electric power supplies before
opening access panel.

Unit must be grounded in accordance
with national and local codes.

WIRING CONNECTIONS

1. Install line voltage power supply to unit from a properly
sized disconnect switch. Any excess high voltage field
wiring should be trimmed or secured away from the
low voltage field wiring.

2. Ground unit at unit disconnect switch or to an earth
ground.

NOTE − For proper voltages, select thermostat wire gauge
per the following table:

Table 5. Wire Run Lengths

Wire run length AWG # Insulation type

Less than 100 feet (30 m) 18

More than 100 feet (30 m) 16

Color−coded with a minimum
temperature rating of 35ºC.

4. Install room thermostat (ordered separately) on an
inside wall approximately in the center of the
conditioned area and five feet (1.5 m) from the floor.
It should not be installed on an outside wall or where
it can be affected by sunlight, drafts or vibrations.

5. Install low voltage wiring from outdoor to indoor unit
and from thermostat to indoor unit as illustrated in
figures 21 and 22.

6. Do not bundle any excess 24VAC control wire inside
control box. Run control wire through installed wire tie
and tighten wire tie to provided low voltage strain relief
and to maintain separation of field installed low and
high voltage circuits.

Thermostat Indoor Unit Outdoor Unit

24V POWER

R

COMMON

C

1ST STAGE

W1

AUXILIARY HEAT

INDOOR BLOWER

G

REVERSING VALVE

O

COMPRESSOR

Y1

(SOME CONNECTIONS MAY NOT APPLY. REFER TO SPECIFIC
THERMOSTAT AND INDOOR UNIT.)

R

C

W1

AUXILIARY HEAT

W2

W3

G

24V POWER

COMMON

1ST STAGE

R

C

W1

O

Y1

Figure 19. Outdoor Unit and Blower Unit Thermostat

Designation

Thermostat Indoor Unit Outdoor Unit

24V POWER

R

COMMON

C

EMERGENCY

E

W1

G

O

Y1

HEAT

1ST STAGE

AUXILIARY HEAT

INDOOR BLOWER

REVERSING VALVE

COMPRESSOR

(SOME CONNECTIONS MAY NOT APPLY. REFER TO
SPECIFIC THERMOSTAT AND INDOOR UNIT.)

R

C

W1

W2

W3

G

24V POWER

COMMON

1ST STAGE

AUXILIARY HEAT

R

C

W1

O

Y1

EMERGENCY

HEAT RELAY

OUTDOOR
THERMOSTAT

3. Connect conduit to the unit using provided conduit
bushing.

505361M 09/07

Figure 20. Outdoor Unit and Blower Unit Thermostat

Designation (with Emergency Heat)

Page 12

READ WARNING AND NOTE

WARNING! − ELECTRIC SHOCK HAZARD. Can cause
INJURY or DEATH. Unit must be grounded in
accordance with national and local codes.

NOTE − For use with copper conductors only. Refer to unit
rating plate for minimum circuit ampacity and maximum
over-current protection size.

GROUND LUG

GROUND

Figure 21. Typical High−Voltage Field Wiring Connection

COMPRESSOR CONTACTOR

L2 L1

CONTROL BOX

GROUND LUG

CONTACTOR

CAPACITOR

DEFROST CONTROL

BOARD (DCB)

Figure 22. Wiring Diagram

Page 13

13HPD SERIES

Temp.
of air
entering
indoor
coil ºF

A

Wet−bulb ºF

53º

DRY

BULB

80 24 24 24 23 23 22 22 22 20 19 18 17 16 15
78 23 23 23 22 22 21 21 20 19 18 17 16 15 14
76 22 22 22 21 21 20 19 19 18 17 16 15 14 13
74 21 21 21 20 19 19 18 17 16 16 15 14 13 12

Dry−bulb

72 20 20 19 18 17 17 16 15 15 14 13 12 11 10

70 19 19 18 18 17 17 16 15 15 14 13 12 11 10

57 58 59 60 61 62 63 64 65 66 67 68 69 70

T

C

Drop

19º

All temperatures are
expressed in ºF

Figure 23. Checking Indoor Airflow over Evaporator Coil using Delta−T Chart

Delta−T

air flowair flow

INDOOR
COIL

Step 1. Determine the desired DTMeasure entering air tempera-
ture using dry bulb (A) and wet bulb (B). DT is the intersecting value of

A and B in the table (see triangle).

Step 2. Find temperature drop across coilMeasure the coil’s dry

bulb entering and leaving air temperatures (A and C). Temperature
Drop Formula: (T

Step 3. Determine if fan needs adjustmentIf the difference be­tween the measured T

B

A

72º

B

64º

WET

BULB

DRY

BULB

+3º, no adjustment is needed. See examples: Assume DT = 15 and A
temp. = 72º, these C temperatures would necessitate stated actions:

Cº T

Drop

53º 19 – 15 = 4 Increase the airflow
58º 14 – 15 = −1 (within +3º range) no change
62º 10 – 15 = −5 Decrease the airflow

Step 4. Adjust the fan speedSee indoor unit instructions to in-

crease/decrease fan speed.

Changing air flow affects all temperatures; recheck temperatures to
confirm that the temperature drop and DT are within +3º.

) = A minus C.

Drop

and the desired DT (T

Drop

– DT = ºF ACTION

–DT) is within

Drop

Start−Up Procedures

IMPORTANT

If unit is equipped with a crankcase heater, it should
be energized 24 hours before unit start−up to
prevent compressor damage as a result of slugging.

1. Rotate fan to check for binding.

2. Inspect all factory− and field−installed wiring for loose
connections.

3. After evacuation is complete, open the liquid line and
vapor line service valves to release the refrigerant
charge (contained in outdoor unit) into the system.

4. Replace the stem caps and tighten as specified in
Operating Service Valves on page 2.

5. Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until you
have consulted with the power company and the
voltage condition has been corrected.

6. Set the thermostat for a cooling demand. Turn on
power to the indoor indoor unit and close the outdoor
unit disconnect switch to start the unit.

7. Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.

8. Check system for sufficient refrigerate by using the
procedures listed under Testing and Charging
System.

SETTING UP TO CHECK CHARGE

1. Close manifold gauge set valves. Connect the center
manifold hose to an upright cylinder of HCFC−22.

2. Connect the manifold gauge set to the unit’s service
ports as illustrated in figure 1.

 low pressure gauge to vapor service port

 high pressure gauge to liquid service port

505361M 09/07

Page 14

COOLING MODE INDOOR AIRFLOW CHECK

Check airflow using the Delta−T (DT) process as illustrated

in figure 23.

HEATING MODE INDOOR AIRFLOW CHECK

Blower airflow (CFM) may be calculated by energizing
electric heat and measuring:

 temperature rise between the return air and supply air

temperatures at the indoor coil blower unit,

 voltage supplied to the unit,
 amperage being drawn by the heat elements.

Then, apply the measurements taken in following formula
to determine CFM:

CFM =

The unit is factory charged with the amount of HCFC−22
refrigerant indicated on the unit rating plate. This charge is
based on a matching indoor coil and outdoor coil with a 15
foot (4.6 m) line set. For varying lengths of line set, refer to
table 6 for refrigerant charge adjustment.

Table 6. Refrigerant Charge per Line Set Lengths

Liquid Line Set

Diameter

3/8 in. (9.5 mm) 3 ounce per 5 ft. (85 g per 1.5 m)

NOTE − *If line length is greater than 15 ft. (4.6 m), add this amount. If
line length is less than 15 ft. (4.6 m), subtract this amount.

The outdoor unit should be charged during warm weather.
However, applications arise in which charging must occur
in the colder months. The method of charging is

determined the outdoor ambient temperature.

Measure the liquid line temperature and the outdoor
ambient temperature as outlined below:

1. Close manifold gauge set valves. Connect the
manifold gauge set to the service valves.

 low pressure gauge to vapor valve service port

 high pressure gauge to liquid valve service port

2. Connect the center manifold hose to an upright
cylinder of HCFC−22.

Amps x Volts x 3.41

1.08 x Temperature rise (F)

Ounces per 5 feet (g per 1.5 m) adjust

from 15 feet (4.6 m) line set*

3. Set the room thermostat to 75° to 80° and a call for
heat. This will create the necessary load for properly
charging the system in the cooling cycle.

4. Use a digital thermometer to record the outdoor
ambient temperature.

5. When the heating demand has been satisfied, switch
the thermostat to cooling mode with a set point of 68F
(20C). When pressures have stabilized, use a digital
thermometer to record the liquid line temperature.

6. The outdoor temperature will determine which
charging method to use. Proceed with the appropriate
charging procedure.

Determining Charge Method

Use figure 24 to determine the correct charging method.

CTXV or RFC

Above 65ºF

(18ºC)?

APPROACH WEIGH-IN or

WHEN TO CHARGE?

 Warm weather best
 Can charge in colder weather

CHARGE METHOD? Determine by:

 Metering device type
 Outdoor ambient temperature

REQUIREMENTS:

 Sufficient heat load in structure
 Indoor temperature between 70-80ºF (21−26ºC)
 Manifold gauge set connected to unit
 Thermometers:

− to measure outdoor ambient temperature

− to measure liquid line temperature

− to measure vapor line temperature

Figure 24. Determining Correct Charging Method

CHARGE USING THE WEIGH−IN METHOD −
OUTDOOR TEMPERATURE < 65F (18C)

If the system is void of refrigerant, or if the outdoor ambient
temperature is cool, first, locate and repair any leaks and
then weigh in the refrigerant charge into the unit.

Below 65ºF

(18ºC)?

SUBCOOLING

1. Recover the refrigerant from the unit.

2. Conduct leak check; evacuate as previously outlined.

3. Weigh in the unit nameplate charge. If weighing
facilities are not available or if charging the unit during
warm weather, use one of the following procedures.

CHARGE USING THE SUBCOOLING METHOD −
OUTDOOR TEMPERATURE < 65°F (18°C)

When the outdoor ambient temperature is below 65°F
(18°C), use the subcooling method to charge the unit. It
may be necessary to restrict the air flow through the
outdoor coil to achieve pressures in the 200−250 psig
(1379−1724 kPa) range. These higher pressures are
necessary for checking the charge. Block equal sections of
air intake panels and move obstructions sideways until the
liquid pressure is in the 200−250 psig (1379−1724 kPa)
range as illustrated in figure 25.

Blocking Outdoor Coil

*Outdoor coil should be blocked one
side at a time with cardboard or plastic
sheet until proper testing pressures
are reached.

cardboard or plastic sheet

*Four−sided unit shown.

Figure 25. Blocking Outdoor Coil

1. With the manifold gauge hose still on the liquid service
port and the unit’s pressure stabilized, use a digital
thermometer to record the liquid line temperature.

2. At the same time, record the liquid line pressure reading.

3. Use a temperature/pressure chart for HCFC−22 to
determine the saturation temperature for the liquid line
pressure reading.

4. Subtract the liquid line temperature from the saturation
temperature (according to the chart) to determine
subcooling.

5. Compare the subcooling value results with those listed
in table 7. If subcooling is greater than shown, recover
some refrigerant. If subcooling is less than shown, add
some refrigerant.

Table 7. Subcooling Values

º Saturation Temperature ºF (ºC)

=

Model −018 −024 −030 −036 −042

°F
(°C)*

NOTE − For best results, use the same electronic
thermometer to check both outdoor-ambient and liquid-line
temperatures. *F: +/−1.0°; C: +/−0.5°

º Liquid Line Temperature ºF (ºC)

º Subcooling Value ºF (ºC)

6

(3.3)11(6)8(4.4)6(3.3)6(3.3)

−048 −060

4

(2.2)

9 (5)

Page 15

13HPD SERIES

CHARGE USING THE APPROACH METHOD −
OUTDOOR TEMPERATURE > 65F (18C)

The following procedure is intended as a general guide and
is for use on expansion valve systems only. For best
results, indoor temperature should be 70°F (21°C) to 80°F
(26°C). Monitor system pressures while charging.

1. Record outdoor ambient temperature using a digital
thermometer.

2. Attach high pressure gauge set and operate unit for
several minutes to allow system pressures to stabilize.

3. Compare stabilized pressures with those listed in table

9. Minor variations in these pressures may be
expected due to differences in installations. Significant
differences could mean that the system is not properly
charged or that a problem exists with some
component in the system. Pressures higher than
those listed indicate that the system is overcharged.
Pressures lower than those listed indicate that the
system is undercharged. Verify adjusted charge using
the approach method.

4. Use the same digital thermometer used to check
outdoor ambient temperature to check liquid line
temperature. Verify the unit charge using the approach
method.

5. The difference between the ambient and liquid
temperatures should match the approach values listed
in table 8. If the values do not agree with the those
listed in table 8, add refrigerant to lower the approach
temperature or recover refrigerant from the system to
increase the approach temperature.

Table 8. Approach Values

º Liquid Line Temperature ºF (ºC)

=

Model −018 −024 −030 −036 −042

°F
(°C)*

NOTE − For best results, use the same electronic thermome­ter to check both outdoor-ambient and liquid-line tempera­tures. *F: + / −1.0°; C: + / −0.5°

º Outdoor Temperature ºF (ºC)

º Approach Temperature ºF (ºC)

7

(3.9)8(4.4)

9 (5)

13

(7.2)7(3.9)

−048 −060

9 (5)

(3.9)

7

INSTALLING SERVICE VALVE CAPS

Disconnect gauge set and re−install all service valve caps.

OUTDOOR UNIT

SERVICE VALVE

INSTALL CAPS

Figure 26. Installing Service Valve Port Caps

Table 9. Normal Operating Pressure − Liquid +10 and Vapor +5 PSIG*

IMPORTANT

Minor variations in these pressures may be expected due to differences in installations. Significant differences
could mean that the system is not properly charged or that a problem exists with some component in the system.

Model 13HPD−018 13HPD−024 13HPD−030 13HPD−036 13HPD−042 13HPD−048 13HPD−060

Temp. 5F (5C)** Liquid / Vapor Liquid / Vapor Liquid / Vapor Liquid / Vapor Liquid / Vapor Liquid / Vapor Liquid / Vapor

Cooling

65 (18) 141 / 81 148 / 80 146 / 78 154 / 78 139 / 67 146 / 75 145 / 72
75 (24) 163 / 82 176 / 82 171 / 79 180 / 80 163 / 74 171 / 77 171 / 75
85 (29) 191 / 84 206 / 83 201 / 80 216 / 81 191 / 81 198 / 78 199 / 77
95 (35) 222 / 85 240 / 84 233 / 81 246 / 81 220 / 84 229 / 79 230 / 78
105 (41) 256 / 87 277 / 86 271 / 81 284 / 82 256 / 85 268 / 81 266 / 79
115 (45) 296 / 89 322 / 87 313 / 83 328 / 85 294 / 87 308 / 81 304 / 81

Heating

50(10) 192 / 64 185 / 60 198 / 58 196 / 58 204 / 59 197 / 39 212 / 57
40 (4) 180 / 53 176 / 50 188 / 47 185 / 47 195 / 49 189 / 31 200 / 47
30 (−1) 172 / 43 165 / 49 175 / 35 176 / 37 184 / 39 181 / 25 187 / 38
20 (−7) 164 / 34 162 / 31 163 / 26 170 / 30 178 / 32 175 / 18 174 / 34

*These are most−popular−match−up pressures. Indoor match up, indoor air quality, and indoor load cause pressures to vary.
**Temperature of the air entering the outside coil.

505361M 09/07

Page 16

System Operation

Defrost System

The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch
is in the ON position, the indoor blower operates
continuously.

LIQUID LINE BI−FLOW FILTER DRIER

The pre−installed liquid line bi−flow filter drier as illustrated
in figure 27 is approved for use with HCFC−22 only. Do not
replace liquid line filter drier with component designed for
use with HFC−410A.

EMERGENCY HEAT FUNCTION (ROOM
THERMOSTAT)

An emergency heat function is designed into some room
thermostats. This feature is applicable when isolation of
outdoor unit is required or when auxiliary electric heat is
staged by outdoor thermostats. When the room thermostat
is placed in the emergency heat position, the outdoor unit
control circuit is isolated from power and field-provided
relays bypass the outdoor thermostats. An amber
indicating light simultaneously comes on to remind the
homeowner that he is operating in the emergency heat
mode.

Emergency heat is usually used during an outdoor
shutdown, but it should also be used following a power
outage if power has been off for over an hour and the
outdoor temperature is below 50°F (10°C). System should
be left in the emergency heat mode at least six hours to
allow the crankcase heater sufficient time to prevent
compressor slugging.

DEFROST

THERMOSTAT

BI−FLOW FILTER

DRIER

CHARGE PORT FOR
FACTORY USE ONLY!

LIQUID LINE

SERVICE PORT

VAPOR LINE SERVICE
PORT

Figure 27. Component Locations

The 13HPD defrost system includes two components: a
defrost thermostat and a defrost control board (DCB).

DEFROST THERMOSTAT

The defrost thermostat as illustrated in figure 27 is located
on the liquid line between the CTXV and the distributor.
When defrost thermostat senses 42°F (5.5°C) or cooler,
the thermostat contacts close and send a signal to the DCB
to start the defrost timing. It also terminates defrost when
the liquid line warms up to 70°F (21°C).

DEFROST CONTROL BOARD (DCB)

The DCB includes the combined functions of a
time/temperature defrost control, defrost relay, diagnostic
LEDs and terminal strip for field wiring connections as
illustrated in figure 28.

FIELD SELECT

TIMING PINS

TEST

PINS

DIAGNOSTIC

COMPRESSOR

DELAY PINS

REVERSING

VALV E

S87

LOW PRESSURE

SWITCH

(OPTIONAL)

DEFROST

THERMOSTAT

S4

HIGH PRESSURE

SWITCH

(OPTIONAL)

LEDS

24V TERMINAL
STRIP
CONNECTIONS

Figure 28. Defrost Control Board (DCB)

The control provides automatic switching from normal
heating operation to defrost mode and back. During
compressor cycle (call for defrost), the control
accumulates compressor run times at 30-, 60-, or
90-minute field−adjustable intervals. If the defrost
thermostat is closed when the selected compressor run
time interval ends, the defrost relay is energized and
defrost begins.

P1  Defrost Temperature Termination and

Test Jumper

Each timing pin selection provides a different
accumulated compressor run time period for one defrost
cycle. This time period must occur before a defrost cycle
is initiated.

The DCB selections are: 30, 60, and 90°F (10, 21, 32 and
38°C). The jumper termination pin is factory set at 90°F
(10°C). If the temperature jumper is not installed, the
default termination temperature is 90°F (32°C). The
maximum defrost period is 14 minutes and cannot be
adjusted.

Page 17

13HPD SERIES

P1

30

60

90 DEFAULT

TEST

Figure 29. P1 Jumper Configurations

A TEST option is provided for troubleshooting. The TEST
mode may be started any time the unit is in the heating
mode and the defrost thermostat is closed or
jumpered.

 If the jumper is in the TEST position at power-up, the

control will ignore the test pins.

 When the jumper is placed across the TEST pins for

two seconds, the control will enter the defrost mode.

 If the jumper is removed before an additional 5−second

period has elapsed (7 seconds total), the unit will
remain in defrost mode until the defrost thermostat
opens or 14 minutes have passed.

 If the jumper is not removed until after the additional

5−second period has elapsed, the defrost will
terminate and the test option will not function again
until the jumper is removed and re−applied.

P5  Compressor 30−Second Delay

The DCB has a field−selectable function to reduce
occasional sounds that may occur while the unit is cycling
in and out of the defrost mode. The compressor will be
cycled off for 30 seconds going in and out of the defrost
mode when the compressor delay jumper is removed.

NOTE − The 30-second OFF cycle is not functional when
jumpering the TEST pins.

Time Delay ByPass

The timed-off delay is five minutes long. The delay helps to
protect the compressor from short-cycling in case the
power to the unit is interrupted or a pressure switch opens.
The delay is bypassed by placing the timer select jumper
across the P1 TEST pins for 0.5 seconds as illustrated in
figure 29.

DS1 and DS2  Diagnostic LEDs

The DCB uses two LEDs (DS1 and DS2) for diagnostics.
The LEDs flash a specific sequence according to the
condition.

Table 10. DS1 and DS2 LED Codes

Defrost Control Board Diagnostic LED

Mode Green LED (DS2) Red LED (DS1)

No power to control OFF OFF

Normal operation /
power to control

Anti-short cycle lock­out

Low pressure switch
fault (Optional)

Low pressure switch
lockout (Optional)

High pressure switch
fault (Optional)

High pressure switch
lockout (Optional)

Simultaneous Slow FLASH

Alternating Slow FLASH

OFF Slow FLASH

OFF ON

Slow FLASH OFF

ON OFF

Maintenance

WARNING

Electric shock hazard. Can cause
injury or death. Before attempting to
perform any service or maintenance,
turn the electrical power to unit OFF at
disconnect switch(es). Unit may have
multiple power supplies.

Before the start of each heating and cooling season, the
following service checks should be performed by a
qualified service technician. First, turn off electrical power
to the unit prior to performing unit maintenance.

 Inspect and clean the outdoor and indoor coils. The

outdoor coil may be flushed with a water hose.

NOTE − It may be necessary to flush the outdoor coil more
frequently if it is exposed to substances which are
corrosive or which block airflow across the coil (e.g., pet
urine, cottonwood seeds, etc.)

 Visually inspect the refrigerant lines and coils for leaks.
 Check wiring for loose connections.
 Check voltage at the indoor and outdoor units (with

units operating).

 Check the amperage draw at the outdoor fan motor,

compressor, and indoor blower motor. Values should
be compared with those given on unit nameplate.

 Check, clean (or replace) indoor unit filters.
 Check the refrigerant charge and gauge the system

pressures.

505361M 09/07

Page 18

Table 11. Defrost Control Board (DCB) Inputs, Outputs and Configurable Settings

DCB
Location

DCB Label or
Description

Purpose Function

P1 TEST Test Mode See Test Mode on page 22 for further details.

The DCB as illustrated in figure 28 has valid selections which
are: 30, 60, and 90°F (−1, 16 and 32°C). The shunt
termination pin is factory set at 50°F (10°C). If the
temperature shunt is not installed, the default termination

P1 30, 60, 90

Defrost Temperature
Termination (Jumper) Pins

temperature is 90°F (32°C).

W1

24VAC Thermostat Input /
Output

24VAC input/output from indoor thermostat to indoor unit.

C 24VAC Common 24VAC common

P2

L Thermostat Service Light Thermostat service light connection.

R 24VAC 24VAC

O Thermostat Input Reversing valve solenoid.

Y1 Thermostat Input Controls the operation of the unit.

The DCB has a field−selectable function to reduce
occasional sounds that may occur while the unit is cycling in
and out of the defrost mode. When a jumper is installed on
the DELAY pins, the compressor will be cycled off for 30

P5 DELAY Delay Mode

seconds going in and out of the defrost mode. Units are
shipped with jumper installed on DELAY pins.

NOTE − The 30 second off cycle is NOT functional when
jumpering the TEST pins on P1.

P6 TST, PS DF, C, R, O, Y1 Factory Test Connectors Factory Use Only.

DS1 RED LED

Diagnostic LED

DS2 GREEN LED

Valid states for DCB’s two LEDs are OFF, ON and
FLASHING which indicate diagnostics conditions that are
described in table 10.

FAN TWO CONNECTORS Condenser Fan Operation These two connections provide power for the condenser fan.

O OUT O OUT 24VAC output 24VAC output connection for reversing valve.

LO−PS LO−PS Low−Pressure Switch Not Used.

DF DF Defrost Thermostat Defrost thermostat connection points.

Y1 OUT Y1 OUT 24VAC Common Output

HS−PS HS−PS

High−Pressure Switch
(Optional)

24VAC common output, switched for enabling compressor
contactor.

Not Used.

L L Line output 24VAC service light output.

24V 24V 24VAC output Not Used.

Page 19

13HPD SERIES

 Check the condensate drain line for free and

unobstructed flow; clean, if necessary.

 Adjust blower speed for cooling. Measure the pressure

drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.

 Check drive belt for wear and proper tension.

If owner reports insufficient cooling, then:

 Measure the temperature drop over the coil.
 Gauged and check refrigerant charge.
 Refer to section on refrigerant charging in this

instruction.

OPTIONAL ACCESSORIES

Refer to the Engineering Handbook for optional
accessories that may apply to this unit. The following may
or may not apply:

 Loss of Charge Kit
 High Pressure Switch Kit
 Mild Weather Kit
 Compressor Monitor
 Compressor Crankcase Heater
 Hail Guards
 Mounting Bases
 Timed Off Control
 Stand−off Kit
 Sound Cover
 Low Ambient Kit
 Monitor Kit
 Dave Lennox Signature Stat Room Thermostat

Homeowner Information

In order to ensure peak performance, your system must be
properly maintained. Clogged filters and blocked airflow
prevent your unit from operating at its most efficient level.

1. Air FilterAsk your Lennox dealer to show you where

your indoor unit’s filter is located. It will be either at the
indoor unit (installed internal or external to the cabinet)
or behind a return air grille in the wall or ceiling. Check
the filter monthly and clean or replace it as needed.

2. Disposable FilterDisposable filters should be

replaced with a filter of the same type and size.

NOTE − If you are unsure about the filter required for your
system, call your Lennox dealer for assistance.

IMPORTANT

Turn off electrical power to the unit at the
disconnect switch before performing any
maintenance. The unit may have multiple power
supplies. Unit may delay coming back on from the
time delay in the thermostat or the defrost control.

3. Reusable FilterMany indoor units are equipped

with reusable foam filters. Clean foam filters with a

mild soap and water solution; rinse thoroughly; allow
filter to dry completely before returning it to the unit or
grille.

NOTE − The filter and all access panels must be in place
any time the unit is in operation.

4. Electronic Air CleanerSome systems are

equipped with an electronic air cleaner, designed to
remove airborne particles from the air passing through
the cleaner. If your system is so equipped, ask your
dealer for maintenance instructions.

5. Indoor UnitThe indoor unit’s evaporator coil is

equipped with a drain pan to collect condensate
formed as your system removes humidity from the
inside air. Have your dealer show you the location of
the drain line and how to check for obstructions. (This
would also apply to an auxiliary drain, if installed.)

IMPORTANT

Sprinklers and soaker hoses should not be installed
where they could cause prolonged exposure to the
outdoor unit by treated water. Prolonged exposure
of the unit to treated water (i.e., sprinkler systems,
soakers, waste water, etc.) will corrode the surface
of steel and aluminum parts and diminish
performance and longevity of the unit.

6. Outdoor UnitMake sure no obstructions restrict

airflow to the outdoor unit. Leaves, trash or shrubs
crowding the unit cause the outdoor unit to work harder
and use more energy. Keep shrubbery trimmed away
from the unit and periodically check for debris which
collects around the unit.

When removing debris from around the unit, be aware
of metal edges on parts and screws. Although special
care has been taken to keep exposed edges to a
minimum, physical contact with metal edges and
corners while applying excessive force or rapid motion
can result in personal injury.

Cleaning of the outdoor unit’s coil should be performed
by a trained service technician. Contact your dealer
and set up a schedule (preferably twice a year, but at
least once a year) to inspect and service your heat
pump system.

HEAT PUMP OPERATION

Your new Lennox heat pump has several characteristics
that you should be aware of:

 Heat pumps satisfy heating demand by delivering

large amounts of warm air into the living space. This
is quite different from gas- or oil-fired furnaces or an
electric furnace which deliver lower volumes of
considerably hotter air to heat the space.

 Do not be alarmed if you notice frost on the outdoor coil

in the winter months. Frost develops on the outdoor
coil during the heating cycle when temperatures are
below 45°F (7°C). An electronic control activates a
defrost cycle lasting 5 to 15 minutes at preset intervals
to clear the outdoor coil of the frost.

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Page 20

 During the defrost cycle, you may notice steam rising

from the outdoor unit. This is a normal occurrence. The
thermostat may engage auxiliary heat during the
defrost cycle to satisfy a heating demand; however,
the unit will return to normal operation at the
conclusion of the defrost cycle.

EXTENDED POWER OUTAGE RESTART
PROCEDURE

If the outdoor temperature is below 50°F (10°C) and power
to your outdoor unit has been interrupted for six hours or
longer, observe the following when restoring power to your
heat pump system.

 Set the room thermostat selector to the EMERGENCY

HEAT setting to obtain temporary heat for a minimum
of six hours. This will allow system refrigerant
pressures and temperatures enough time to return to
a stabilized condition.

 In Emergency Heat mode, all heating demand is

satisfied by auxiliary heat; heat pump operation is
locked out. After a six-hour warm-up period, the
thermostat can then be switched to the HEAT setting
and normal heat pump operation may resume.

NON−PROGRAMMABLE THERMOSTAT OPERATION

Though your thermostat may vary somewhat from the
description below, its operation will be similar.

Temperature Setting Levers

Most heat pump thermostats have two temperature
selector levers: one for heating and one for cooling. Set the
levers or dials to the desired temperature setpoints for both
heating and cooling. Avoid frequent temperature
adjustment; turning the unit off and back on before
pressures equalize puts stress on the unit compressor.

Fan Switch

In AUTO or INT (intermittent) mode, the blower operates
only when the thermostat calls for heating or cooling. This
mode is generally preferred when humidity control is a
priority. The ON or CONT mode provides continuous
indoor blower operation, regardless of whether the
compressor or auxiliary heat are operating. This mode is
required when constant air circulation or filtering is desired.

System Switch

Set the system switch for heating, cooling or auto
operation. The auto mode allows the heat pump to
automatically switch from heating mode to cooling mode to
maintain predetermined comfort settings. Many heat
pump thermostats are also equipped with an emergency
heat mode which locks out heat pump operation and
provides temporary heat supplied by the auxiliary heat.

Indicating Light

Most heat pump thermostats have an amber light which
indicates when the heat pump is operating in the
emergency heat mode.

Temperature Indicator

The temperature indicator displays the actual room
temperature.

PROGRAMMABLE THERMOSTATS

Your Lennox system may be controlled by a
programmable thermostat. These thermostats provide the
added feature of programmable time-of-day setpoints for
both heating and cooling. Refer to the user’s information
manual provided with your particular thermostat for
operation details.

PRESERVICE CHECK

If your system fails to operate, check the following before
calling for service:

 Check to see that all electrical disconnect switches are

ON.

 Make sure the room thermostat temperature selector

and system switch (HEAT, COOL and AUTO) are
properly set.

 Check for any blown fuses or tripped circuit breakers.

 Make sure unit access panels are in place.

 Make sure air filter is clean.

 If service is needed, locate and write down the unit

model number and have it handy before calling.

Page 21

13HPD SERIES

Start−Up and Performance Checklist

Customer Address

Indoor Unit Model Serial

Outdoor Unit Model Serial

Notes:

START−UP CHECKS

Refrigerant Type:

Rated Load Amps Actual Amps Rated Volts Actual Volts

Condenser Fan Full Load Amps Actual Amps:

COOLING MODE

Vapor Pressure: Liquid Pressure:

Supply Air Temperature: Ambient Temperature: Return Air Temperature:

HEATING MODE

Vapor Pressure: Liquid Pressure:

Supply Air Temperature: Ambient Temperature: Return Air Temperature:

System Refrigerant Charge (Refer to manufacturer’s information on unit or installation instructions for required subcooling and
approach temperatures.)

Subcooling:

Saturated Condensing Temperature (A)

minus Liquid Line Temperature (B)

Approach:

Liquid Line Temperature (A)

minus Outdoor Air Temperature (B)

Indoor Coil Temp. Drop (18 to 22°F) A

Return Air Temperature (A)

minus Supply Air Temperature (B)

A



A





B

B

B

SUBCOOLING

=

APPROACH

=

COIL TEMP DROP

=

505361M 09/07

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