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505331M 06/09
CAUTION
This procedure should not be performed on
systems which contain contaminants (Example:
compressor burn out).
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
.
REQUIRED EQUIPMENT
Equipment required to flush the existing line set and indoor
unit coil:
S
Two clean HCFC−22 recovery bottles,
S
Oilless recovery machine with pump-down feature,
S
Two gauge sets (one for HCFC−22; one for
HFC−410A).
FLUSHING PROCEDURE
1. Connect the following:
S
HCFC−22 cylinder with clean refrigerant to the
suction service valve,
S
HCFC−22 gauge set to the liquid line valve,
S
Recovery machine with an empty recovery tank to
the gauge set.
2. Set the recovery machine for liquid recovery and start
the recovery machine. Open the gauge set valves to
allow the recovery machine to pull a vacuum on the
existing system line set and indoor unit coil.
3. Invert the cylinder of clean HCFC−22 and open its
valve to allow liquid refrigerant to flow into the system
through the suction line valve. Allow the refrigerant to
pass from the cylinder and through the line set and the
indoor unit coil before it enters the recovery machine.
4. After all of the liquid refrigerant has been recovered,
switch the recovery machine to suction recovery so
that all of the HCFC−22 suction is recovered. Allow the
recovery machine to pull a vacuum on the system.
5. Close the valve on the inverted HCFC−22 drum and
the gauge set valves. Pump the remaining refrigerant
out of the recovery machine and turn the machine off.
Installing New Indoor Metering Device13
XP19 units use CTXV for metering refrigerant only. This
section provides instructions on installing CTXV
refrigerant metering device.
1
2
3
4
5
6
7
8
9
10
11 12
1/8 TURN
1
2
3
4
5
6
7
8
9
10
11 12
1/2 TURN
Figure 24. Tightening Distance
TYPICAL CTXV INSTALLATION PROCEDURE
The CTXV unit 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
manner that will provide access for field servicing of the
CTXV. Refer to Figure 25 for reference during installation
of CTXV unit.
TWO PIECE
PATCH PLATE
(UNCASED COIL
ONLY)
SUCTION
LINE
LIQUID LINE
ORIFICE
HOUSING
DISTRIBUTOR
TUBES
LIQUID
LINE
MALE EQUALIZER LINE
FITTING (SEE FIGURE 27
FOR FURTHER DETAILS)
SENSING
LINE
EQUALIZER
LINE
CTXV
TEFLON
RING
(Uncased Coil Shown)
SENSING BULB INSULATION IS
REQUIRED IF MOUNTED EXTERNAL
TO THE COIL CASING. SEE FIGURE 26
FOR BULB POSITIONING.
STUB END
TEFLON
RING
LIQUID LINE ASSEMBLY
WITH BRASS NUT
DISTRIBUTOR
ASSEMBLY
Figure 25. Typical TXV Installation
1. Remove the field−provided fitting that temporary
reconnected the liquid line to the indoor unit’s
distributor assembly.
2. Install one of the provided Teflon rings around the
stubbed end of the CTXV and lightly lubricate the
connector threads and expose surface of the Teflon
ring with refrigerant oil.
3. Attach the stubbed end of the CTXV to the liquid line
orifice housing. Finger tighten and use an appropriately
