Flushing The System - Lennox XC14 Installation Instructions Manual

TYPICAL FIXED ORIFICE REMOVAL PROCEDURE
DISTRIBUTOR TUBES
LIQUID LINE ORIFICE HOUSING
TEFLON RING
DISTRIBUTOR
ASSEMBLY
VALVE STEM
VALVE STEM CAP
Figure 20. Typical Fixed Orifice 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. 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 fixed orifice, valve stem
assembly if present and Teflon ring as illustrated in
figure 20.
5. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit's liquid line orifice housing.
TYPICAL TXV REMOVAL PROCEDURE
(Uncased Coil Shown)
TWO PIECE
PATCH PLATE LIQUID LINE
(UNCASED COIL
ORIFICE
ONLY)
HOUSING
DISTRIBUTOR
TUBES
DISTRIBUTOR
EQUALIZER
ASSEMBLY
LINE
MALE EQUALIZER
LINE FITTING
SENSING
BULB
Figure 21. Typical TXV Removal
505367M 04/08
REMOVE AND DISCARD
VALVE STEM ASSEMBLY
FIXED
(IF PRESENT)
ORIFICE
BRASS NUT
LIQUID LINE ASSEMBLY
(INCLUDES STRAINER)
(Uncased Coil Shown)
STUB END
TXV
TEFLON
RING
TEFLON
RING
SENSING
LINE
LIQUID LINE ASSEMBLY
WITH BRASS NUT
SUCTION
LINE
LIQUID
LINE
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 as illustrated in
figure 21.
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 as
illustrated in figure 21.
8. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit's liquid line orifice housing.

Flushing the System

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
prohibits the intentional venting of HFC refrigerants
during maintenance, service, repair and disposal of
appliance. Approved
recycling or reclaiming must be followed.
If the original system used:
S
HCFC−22 refrigerant, then flush the system using the
procedure provided in this section.
S
HFC−410A refrigerant, then proceed to Installing New
Refrigerant Metering Device.
Page 12
Protection Agency
methods of recovery,
(EPA)