Page 11
XP19 SERIES
4. Remove and discard fixed orifice, valve stem
assembly if present and Teflon washer as illustrated in
Figure 21.
5. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit’s liquid line orifice housing.
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)
Figure 21. Typical Fixed Orifice Removal
TYPICAL TXV REMOVAL PROCEDURE
TWO PIECE
PATCH PLATE
(UNCASED COIL
ONLY)
SUCTION
LINE
DISTRIBUTOR
ASSEMBLY
DISTRIBUTOR
TUBES
LIQUID
LINE
MALE EQUALIZER LINE
FITTING
SENSING
LINE
EQUALIZER
LINE
TXV
TEFLON
RING
(Uncased Coil Shown)
STUB END
TEFLON
RING
SENSING BULB
LIQUID LINE
ORIFICE HOUSING
LIQUID LINE ASSEMBLY
WITH BRASS NUT
Figure 22. Typical TXV Removal
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. Disconnect the equalizer line from the TXV equalizer
line fitting on the suction line.
4. Remove the suction line sensing bulb.
5. Disconnect the liquid line from the TXV at the liquid line
assembly.
6. Disconnect the TXV from the liquid line orifice housing.
Take care not to twist or damage distributor tubes
during this process.
7. Remove and discard TXV and the two Teflon rings.
8. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit’s liquid line orifice housing.
Flushing the System12
IMPORTANT
The line set and indoor unit coil must be flushed
with at least the same amount of clean refrigerant
that previously charged the system. Check the
charge in the flushing cylinder before proceeding.
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.
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.
LOW
PRESSURE
HIGH
PRESSURE
EXISTING
INDOOR
UNIT
GAUGE
MANIFOLD
INVERTED HCFC−22 CYLINDER
CONTAINS CLEAN HCFC−22 TO
BE USED FOR FLUSHING.
LIQUID LINE SERVICE VALVE
INLET
DISCHARGE
TANK
RETURN
CLOSED
OPENED
RECOVERY
CYLINDER
NOTE − THE INVERTED HCFC−22 CYLINDER MUST CONTAIN AT LEAST THE SAME
AMOUNT OF REFRIGERANT AS WAS RECOVERED FROM THE EXISTING SYSTEM.
RECOVERY MACHINE
NEW
OUTDOOR
UNIT
SUCTION LINE
SERVICE VALVE
SUCTION
LIQUID
Figure 23. Typical Flushing Connection
