Removing Indoor Unit Metering Device - Lennox TSA036H4N41 Installation Instructions Manual

1
CUT AND DEBUR
7
INSTALL CORE ONLY FOR
BOTH SERVICE PORTS AFTER
THEY HAVE COOLED.
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 suction service
valve.
NOTE − The RFCIV or TXV metering device at the indoor
unit 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.
6. Braze the liquid line to the liquid line service valve.
Turn off nitrogen flow. Repeat procedure starting at
paragraph 4 for brazing the suction line to service
valve.
7. 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 caps if desired to close off refrigerant
ports.

Removing Indoor Unit Metering Device

Remove the existing HCFC−22 fixed orifice or thermal
expansion valve from the indoor coil. The existing indoor
unit HCFC−22 metering device is not approved for use with
HFC−410A refrigerant and may prevent proper flushing.
506083−01 03/08
2
REMOVE CAP AND CORE FROM
BOTH LIQUID AND SUCTION
SERVICE PORTS
SERVICE PORT MUST BE
OPEN TO ALLOW EXIT
POINT FOR NITROGEN
SUCTION LINE
INDOOR UNIT
LIQUID LINE
6
BRAZE LINE SET
Figure 14. Brazing Connections
3
ATTACH
GAUGES
SERVICE
VALVE
SERVICE
VALVE
5
FLOW NITROGEN
REPLACEMENT PARTS
If replacement parts are necessary for the indoor unit,
order kit 69J46. The kit includes the following:
LIQUID LINE ORIFICE HOUSINGS (10)
TEFLON RINGS (20)
LIQUID LINE ASSEMBLIES
(INCLUDES STRAINER) (10)
Figure 15. 69J46 Kit Components
TYPICAL FIXED ORIFICE REMOVAL PROCEDURE
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 liquid
line orifice housing. Take care not to twist or damage
distributor tubes during this process.
4. Remove and discard Teflon ring, orifice, and valve
stem assembly if present as illustrated in figure 16.
5. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit's liquid line orifice housing.
Page 8
OUTDOOR
UNIT
4
WRAP
NITROGEN
SERVICE
VALVE
BRASS NUTS (10)
LIQUID LINE
ASSEMBLY
PISTON
RETAINER
STRAINER
COPPER
TUBE