Lennox 14HPX User manual

11/09 506377−01
*2P1109* *P506377-01*
Page 1
2009 Lennox Industries Inc.
Dallas, Texas, USA
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
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 licensed
professional installer (or equivalent) or a service agency.
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.
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.
WARNING
Electric Shock Hazard. Can cause injury
or death. Unit must be grounded in
accordance with national and local
codes.
Line voltage is present at all components
when unit is not in operation on units with
single-pole contactors. Disconnect all
remote electric power supplies before
opening access panel. Unit may have
multiple power supplies.
INSTALLATION
INSTRUCTIONS
Merit®Series 14HPX Units
HEAT PUMP UNITS
506377−01
11/09
Supersedes 505,243M
TABLE OF CONTENTS
Shipping and Packing List 1. . . . . . . . . . . . . . . . . . . . . . . .
General 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Typical Unit Parts Arrangement 2. . . . . . . . . . . . . . . . . . .
Model Number Identification 3. . . . . . . . . . . . . . . . . . . . . .
General Information 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Gauge Set and Service Valves 3. . . . . . . . . . .
Recovering Refrigerant from Existing System 5. . . . . . .
New Outdoor Unit Placement 6. . . . . . . . . . . . . . . . . . . . .
New or Replacement Line Set 6. . . . . . . . . . . . . . . . . . . . .
Metering Devices and Flushing the System 10. . . . . . . .
Testing for Leaks 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evacuating the System 12. . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Connections 13. . . . . . . . . . . . . . . . . . . . . . . . . .
Servicing Unit Delivered Void of Charge 16. . . . . . . . . . .
Start−Up 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Refrigerant 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removing and Installing Louvers 21. . . . . . . . . . . . . . . . .
System Operation 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defrost System 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Start−Up and Performance Checklist 28. . . . . . . . . . . . . .
Shipping and Packing List
Check the unit components for shipping damage. If you
find any damage, immediately contact the last carrier.
1 − Assembled 14HPX outdoor unit
General
The Merit®14HPX model is designed for use with
HFC−410A refrigerant only. This unit must be installed with
an approved indoor air handler or coil. See the Lennox
14HPX Engineering Handbook for approved indoor
component matchups.
IMPORTANT
This model is designed for use in expansion valve
systems only. An indoor expansion valve approved for
use with HFC−410A refrigerant must be ordered
separately, and installed prior to operating the system.
Litho U.S.A.

Page 2
506377−01 11/09
Unit Dimensions − inches (mm)
SIDE VIEW
SUCTION AND LIQUID
LINE CONNECTION
DISCHARGE AIR
SIDE VIEW
OUTDOOR
COIL FAN
COMPRESSOR
A
B
A
OPTIONAL UNIT
STANDOFF KIT (4)
(FIELD INSTALLED)
Model No. A B C
14HPX−018 24−1/4 (616) 29−1/4 (743) 28−1/2 (724)
14HPX−024 24−1/4 (616) 29−1/4 (743) 28−1/2 (724)
14HPX−030 24−1/4 (616) 33−1/4 (845) 32−1/2 (826)
14HPX−036 32−1/4 (819) 29−1/4 (743) 28−1/2 (724)
14HPX−042 32−1/4 (819) 37−1/4 (946) 36−1/2 (927)
14HPX−048 32-1/4 (819) 37−1/4 (946) 36−1/2 (927)
14HPX−060 32-1/4 (819) 43−1/4 (1099) 42−1/4 (1073)
Typical Unit Parts Arrangement
COMPRESSOR
HARNESS
LIQUID LINE SERVICE
VALVE
VAPOR LINE
SERVICE VALVE
BI−FLOW FILTER
DRIER
DISCHARGE
LINE
HIGH PRESSURE
SWITCH (S4)
COMPRESS0R
TRUE SUCTION
PORT
CHECK EXPANSION
VALVE
DEFROST
THERMOSTAT
EQUALIZER LINE
MUFFLER
REVERSING
VALVE
REVERSING VALVE
SOLENOID
LOW PRESSURE
SWITCH
NOTE  PLUMBING LAYOUT AND COMPRESSOR TYPE MAY VARY SLIGHTLY
BETWEEN MODEL SIZES.
GROUND
LUG
CONTACTOR
CONTROL
CONTROL WIRE
LOOP
CUTOUT FOR HIGH
VOLTAGE CONDUIT
DEFROST
CONTROL
BOARD
CAPACITOR

Page 3
14HPX SERIES
Model Number Identification
HP X14 024 −
Unit Type
HP = Heat Pump
Refrigerant
X = R−410A
Cooling Capacity − Tons
018 = 1.5
024 = 2
030 = 2.5
036 = 3
042 = 3.5
048 = 4
060 = 5
Minor Revision Number
Nominal SEER
2
Voltage
230 = 208/230V−1phase−60hz
230
−−
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
General Information
These instructions are intended as a general guide and do
not supersede national or local codes in any way. Consult
authorities having jurisdiction before installation.
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.
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.
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.
IMPORTANT
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.

Page 4
506377−01 11/09
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 1 provides information
on how to access and operating both angle and ball service
valves.
(VALVE STEM SHOWN
CLOSED) INSERT HEX
WRENCH HERE
VALVE STEM
FRONT-SEATED
TO OUTDOOR
UNIT
SERVICE PORT
CORE
TO INDOOR
UNIT
SERVICE PORT
SERVICE PORT CAP
CLOSED TO BOTH
INDOOR AND OUTDOOR
UNITS
STEM CAP
ANGLE−TYPE
SERVICE VALVE
(FRONT−SEATED
CLOSED)
SERVICE PORT
SERVICE PORT
CORE
TO OUTDOOR UNIT
STEM CAP
(VALVE STEM
SHOWN OPEN)
INSERT HEX
WRENCH HERE
SERVICE PORT CAP
TO INDOOR
UNIT
OPEN TO BOTH INDOOR AND
OUTDOOR UNITS
ANGLE−TYPE SERVICE VALVE
(BACK−SEATED OPENED)
BALL (SHOWN CLOSED)
SERVICE PORT CORE
TO INDOOR UNIT
TO OUTDOOR UNIT
TO OPEN ROTATE STEM
COUNTERCLOCKWISE 90°.
TO CLOSE ROTATE STEM
CLOCKWISE 90°.
SERVICE PORT
SERVICE PORT CAP
STEM CAP
VALVE STEM
WHEN SERVICE VALVE IS CLOSED, THE SERVICE PORT IS OPEN TO THE
LINE SET AND INDOOR UNIT.
BALL−TYPE SERVICE
VALVE
SERVICE VALVES
VARIOUS TYPES
WHEN SERVICE VALVE IS OPEN, THE SERVICE PORT IS OPEN TO LINE SET,
INDOOR AND OUTDOOR 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 fol-
lows:
123
4
5
6
7
8
9
10
11 12
1/6 TURN
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.
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°.
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:
With Torque Wrench: Finger tighten and then torque cap per Table 1.
Without Torque Wrench: Finger tighten and use an appropriately sized wrench to turn
an additional 1/12 turn clockwise.
NOTE  A label with specific torque requirements may be affixed to the stem cap. If the label is present, use the specified torque.
123
4
5
6
7
8
9
10
11 12
1/6 TURN
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.
Figure 1. Angle and Ball Service Valves

Page 5
14HPX SERIES
Recovering Refrigerant from Existing System
SERVICE
DISCONNECT
SWITCH
MAIN FUSE BOX/
BREAKER PANEL
Disconnect all power to the existing outdoor unit at the service
disconnect switch or main fuse box/breaker panel.
DISCONNECT POWER CONNECT MANIFOLD GAUGE SET
MANIFOLD GAUGES
RECOVERY MACHINE
CLEAN RECOVERY
CYLINDER
OUTDOOR UNIT
HIGH
LOW
Connect a gauge set, clean recovery cylinder and a recovery
machine to the service ports of the existing unit. Use the
instructions provided with the recovery machine to make the
connections.
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 to
flush the system.
Remove all 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 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:
AStart the existing system in the cooling mode and close the liquid line valve.
BUse 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.
CWhen the low side system pressures reach 0 psig, close the vapor line valve.
DCheck gauges after shutdown to confirm that the valves are not allowing refrigerant to flow back into the low side of the system.
RECOVERING
REFRIGERANT FROM SYSTEM
Remove existing refrigerant using one of the following procedures:
RECOVERING REFRIGERANT
IMPORTANT  Some system configurations may contain higher than normal refrigerant charge due to either large internal coil volumes,
and/or long line sets.
12
3

Page 6
506377−01 11/09
New Outdoor Unit Placement
See Unit Dimensions on Page 2 for sizing mounting slab,
platforms or supports. Refer to Figure 2 for mandatory
installation clearance requirements.
*
**
*
NOTES:
Service panel access clearance of 30 in. (762 mm) must be
maintained.
Clearance to one of the other three sides must be 36 in. (914
mm).
Clearance on one of the remaining two sides may be 12 in. (305
mm) and the final side may be 6 in. (152 mm).
Clearance required on top of unit is 48 in. (1219 mm).
A clearance of 24 in. (610 mm) must be maintained between two
units.
Figure 2. Installation Clearances
CAUTION
In order to avoid injury, take proper precaution when lift-
ing 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.
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 3.
INSTALL UNIT AWAY
FROM WINDOWS
TWO 90ELBOWS INSTALLED IN LINE SET
WILL REDUCE LINE SET VIBRATION
Figure 3. Outside Unit Placement
PLACING 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.
GROUND LEVEL
MOUNTING
SLAB
BUILDING
STRUCTURE
DISCHARGE AIR
Figure 4. Typical Slab Mounting at Ground Level
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.
INSTALLING OUTDOOR UNIT ON ROOF
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.
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 3.

Page 7
14HPX SERIES
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 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.
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.
Table 2. Refrigerant Line Set (MM)
Model
Field
Connections Recommended Line Set
Liquid
Line
Vapor
Line
Liquid
Line
Vapor
Line
L15
Line Sets
−018
−024
−030
3/8 in.
(10 mm)
3/4 in
(19 mm)
3/8 in.
(10
mm)
3/4 in
(19
mm)
L15−41
15 ft. − 50 ft.
(4.6 m − 15
m)
−036
−042
−048
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)
−060 3/8 in.
(10 mm)
1−1/8 in.
(29 mm)
3/8 in.
(10
mm)
1−1/8
in.
(29
mm)
Field
Fabricated
NOTE  Some applications may required a field provided 7/8" to
1−1/8" adapter
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 (14HPX) 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 14HPX 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 14HPX unit.
Typically a liquid line used to meter flow is 1/4" in diameter
and copper.
LINE SET ISOLATION
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
The Environmental Protection Agency (EPA) prohibits
the intentional venting of HFC refrigerants during
maintenance, service, repair and disposal of appliance.
Approved methods of recovery, recycling or reclaiming
must be followed.
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.

Page 8
506377−01 11/09
ANCHORED HEAVY NYLON
WIRE TIE OR AUTOMOTIVE
MUFFLER-TYPE HANGER
STRAP LIQUID LINE TO
VAPOR LINE
WALL
STUD
LIQUID LINE
NON−CORROSIVE
METAL SLEEVE
VAPOR LINE − WRAPPED
IN ARMAFLEX
AUTOMOTIVE
MUFFLER-TYPE HANGER
REFRIGERANT LINE SET  TRANSITION
FROM VERTICAL TO HORIZONTAL
Line Set Isolation  The following illustrations are
examples of proper refrigerant line set isolation:
STRAPPING
MATERIAL (AROUND
VAPOR LINE ONLY)
TAPE OR
WIRE TIE
WIRE TIE (AROUND
VAPOR LINE ONLY)
FLOOR JOIST OR
ROOF RAFTER
TAPE OR
WIRE TIE
To hang line set from joist or rafter, use either metal strapping material
or anchored heavy nylon wire ties.
8 FEET (2.43 METERS)
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.
FLOOR JOIST OR
ROOF RAFTER
REFRIGERANT LINE SET  INSTALLING
HORIZONTAL RUNS
NOTE  Similar installation practices should be used if line set is
to be installed on exterior of outside wall.
PVC
PIPE
FIBERGLASS
INSULATION
CAULK
OUTSIDE
WALL
VAPOR LINE WRAPPED
WITH ARMAFLEX
LIQUID
LINE
OUTSIDE WALL LIQUID LINE
VAPOR LINE
WOOD BLOCK
BETWEEN STUDS
STRAP
WOOD BLOCK
STRAP
SLEEVE
WIRE TIE
WIRE TIE
WIRE TIE
INSIDE WALL
REFRIGERANT LINE SET  INSTALLING
VERTICAL RUNS (NEW CONSTRUCTION SHOWN)
INSTALLATION
LINE SET
NOTE  Insulate liquid line when it is routed through areas where the
surrounding ambient temperature could become higher than the
temperatureof the liquid line or when pressure drop is equal to or greater
than 20 psig.
NON−CORROSIVE
METAL SLEEVE
IMPORTANT  Refrigerant lines must not contact structure.
NON−CORROSIVE
METAL SLEEVE
8 FEET (2.43 METERS)
IMPORTANT  Refrigerant lines must not contact wall
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
14HPX SERIES
CUT AND DEBUR
CAP AND CORE REMOVAL
Cut ends of the refrigerant lines square
(free from nicks or dents) and debur the
ends. The pipe must remain round and do
not pinch end of the line.
Remove service cap and core
from both the vapor and liquid line
service ports.
ATTACHED GAUGES
OUTDOOR
UNIT
LIQUID LINE
VAPOR LINE
LIQUID LINE SERVICE
VALVE
VAPOR LINE
SERVICE
VALVE
ATTACH
GAUGES
INDOOR
UNIT
SERVICE PORT MUST BE OPEN TO ALLOW EXIT
POINT FOR NITROGEN
AConnect gauge set low pressure side to liquid line service
valve.
BConnect gauge set center port to bottle of nitrogen with
regulator.
NITROGEN
HIGHLOW
USE REGULATOR TO FLOW
NITROGEN AT 1 TO 2 PSIG.
WRAP SERVICE VALVE FLOW NITROGEN
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.
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.
NOTE  The fixed orifice or check
expansion valve metering device at the
indoor unit will allow low pressure
nitrogen to flow through the system.
NITROGEN
HIGH
LOW
USE REGULATOR TO
FLOW NITROGEN AT 1
TO 2 PSIG.
BRAZE LINE SET
INSTALL SERVICE PORT CAPS ONLY
Braze the liquid line to the liquid line
service valve. Turn off nitrogen flow.
After all connections have been brazed, disconnect manifold gauge
set from service ports, cool down piping with wet rag and remove all
wrappings. Do not reinstall cores until after evacuation procedure.
Reinstall service port caps if desired to close off refrigerant ports.
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.
SERVICE PORT CORE
SERVICE PORT CAP
SERVICE PORT
WARNING  Allow braze joint to cool before removing the
wet rag from the service valve. (TEMPERATURES ABOVE
250ºF CAN DAMAGE VALVE SEALS
CONNECTIONS
BRAZING
12
3
45
6
7
B
A
POINT FLAME AWAY FROM
SERVICE VALVE
NOTE − Use silver alloy brazing rods with five or six percent minimum silver
alloy for copper−to−copper brazing, 45 percent alloy for copper−to−brass and
copper−to−steel brazing.
Figure 6. Brazing Connections

Page 10
506377−01 11/09
Metering Devices and Flushing the System
SENSING
LINE
TEFLON RING
FIXED ORIFICE
(Uncased Coil Shown)
BRASS NUT
LIQUID LINE ASSEMBLY
(INCLUDES STRAINER)
LIQUID LINE ORIFICE HOUSING
DISTRIBUTOR TUBES
DISTRIBUTOR
ASSEMBLY
REMOVE AND DISCARD
WHITE TEFLON SEAL (IF
PRESENT)
AOn fully cased coils, remove the coil access and plumbing panels.
BRemove any shipping clamps holding the liquid line and distributor
assembly.
CUsing two wrenches, disconnect liquid line from liquid line orifice
housing. Take care not to twist or damage distributor tubes during
this process.
DRemove and discard fixed orifice, valve stem assembly if present
and Teflon washer as illustrated above.
EUse a field−provided fitting to temporary reconnect the liquid line to
the indoor unit’s liquid line orifice housing.
TYPICAL FIXED ORIFICE REMOVAL
PROCEDURE
TYPICAL CHECK EXPANSION VALVE
REMOVAL AND REPLACEMENT PROCEDURE
TWO PIECE PATCH PLATE
(UNCASED COIL ONLY)
VAPOR
LINE
DISTRIBUTOR
ASSEMBLY
DISTRIBUTOR
TUBES
LIQUID
LINE
MALE EQUALIZER
LINE FITTING
EQUALIZER
LINE
CHECK
EXPANSION
VALVE
TEFLON
RING
(Uncased Coil Shown)
STUB END
TEFLON
RING
SENSING BULB
LIQUID LINE
ORIFICE
HOUSING
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
AOn fully cased coils, remove the coil access and plumbing panels.
BRemove any shipping clamps holding the liquid line and distributor as-
sembly.
CDisconnect the equalizer line from the check expansion valve equaliz-
er line fitting on the vapor line.
DRemove the vapor line sensing bulb.
EDisconnect the liquid line from the check expansion valve at the liquid
line assembly.
FDisconnect the check expansion valve from the liquid line orifice hous-
ing. Take care not to twist or damage distributor tubes during this pro-
cess.
GRemove and discard check expansion valve and the two Teflon rings.
HUse a field−provided fitting to temporary reconnect the liquid line to the
indoor unit’s liquid line orifice housing.
IReverse above order to install.
LOW HIGH
EXISTING
INDOOR
UNIT
GAUGE
MANIFOLD
INVERTED CYLINDER
CONTAINS CLEAN TO
BE USED FOR
FLUSHING.
LIQUID LINE SERVICE
VALVE
INLET
DISCHARGE
TANK
RETURN
CLOSED
OPENED
RECOVERY
CYLINDER
RECOVERY MACHINE
NEW
OUTDOOR
UNIT
VAPOR LINE
SERVICE VALVE
VAPOR
LIQUID
1
AInverted cylinder with clean refrigerant to the vapor service valve.
Bgauge set (low side) to the liquid line valve.
Cgauge set center port to inlet on the recovery machine with an empty
recovery tank to the gauge set.
DConnect recovery tank to recovery machines per machine
instructions.
CONNECT GAUGES AND EQUIPMENT FOR
FLUSHING PROCEDURE
A
B
C
D
B
OR
FLUSHING LINE SET
ASet the recovery machine for liquid recovery and start the recov-
ery machine. Open the gauge set valves to allow the recovery
machine to pull a vacuum on the existing system line set and in-
door unit coil.
BInvert the cylinder of clean and open its valve to allow liquid re-
frigerant to flow into the system through the vapor line valve. Al-
low the refrigerant to pass from the cylinder and through the line
set and the indoor unit coil before it enters the recovery machine.
CAfter all of the liquid refrigerant has been recovered, switch the
recovery machine to vapor recovery so that all of the vapor is
recovered. Allow the recovery machine to pull down to 0 the sys-
tem.
DClose the valve on the inverted drum and the gauge set valves.
Pump the remaining refrigerant out of the recovery machine and
turn the machine off.
The line set and indoor unit coil must be flushed with at least the
same amount of clean refrigerant that previously charged the sys-
tem. Check the charge in the flushing cylinder before proceeding.
LINE SET AND INDOOR COIL (1 OF 2)
FLUSHING
1
2
3
CAUTION  This procedure should not be performed on systems
which contain contaminants (Example compressor burn out.