INSTALLING TXV IN PLACE OF PISTON
1. Pump system down to 2 psig and recover refrigerant.
2. Remove hex nut from piston body. Use backup wrench on
fan coils.
3. Remove and discard factory-installed piston. Be sure Teflon
seal is in place.
4. Reinstall hex nut. Finger tighten nut plus 1/2 turn.
NOTE:
If the piston is not removed from the body, TXV will not
function properly.
CAUTION:
To prevent damage to the unit, use a brazing
shield and wrap TXV with wet cloth or use heat sink
material.
5. Install TXV on indoor coil liquid line. Sweat swivel adapter
to inlet of indoor coil and attach to TXV outlet. Use backup
wrench to avoid damage to tubing or valve. Sweat inlet of
TXV, marked “IN” to liquid line. Avoid excessive heat
which could damage valve.
6. Install vapor elbow with equalizer adapter to suction tube of
line set and suction connection to indoor coil. Adapter has
a 1/4-in. male connector for attaching equalizer tube.
7. Connect equalizer tube of TXV to 1/4-in. equalizer fitting
on vapor line adapter.
8. Attach TXV bulb to horizontal section of suction line using
clamps provided. Insulate bulb with field-supplied insula-
tion tape. See Fig. 5 for correct positioning of sensing bulb.
9. Proceed with remainder of unit installation.
REPLACING TXV ON R-22 INDOOR COIL
1. Pump system down to 2 psig and recover refrigerant.
2. Remove coil access panel and fitting panel from front of
cabinet.
3. Remove TXV support clamp using a 5/16-in. nut driver.
Save the clamp.
4. Remove R-22 TXV using a backup wrench on flare
connections to prevent damage to tubing.
5. Using wire cutters, cut equalizer tube off flush with vapor
tube inside cabinet.
6. Remove bulb from vapor tube inside cabinet.
IMPORTANT:
Route the equalizer tube of Puron® TXV through
suction line connection opening in fitting panel prior to replacing
fitting panel around tubing.
7. Braze equalizer stub-tube closed. Use protective barrier as
necessary to prevent damage to drain pan.
8. Install TXV with 3/8-in. copper tubing through small hole
in service panel. Use wrench and backup wrench, to avoid
damage to tubing or valve, to attach TXV to distributor.
9. Reinstall TXV support clamp (removed in item 3).
10. Attach TXV bulb to vapor tube inside cabinet, in same
location as original was when removed, using supplied bulb
clamps (nylon or copper). See Fig. 5 for correct positioning
of sensing bulb.
11. Route equalizer tube through suction connection opening
(large hole) in fitting panel and install fitting panel in place.
12. Sweat inlet of TXV, marked
″
IN
″
to liquid line. Avoid
excessive heat which could damage valve.
13. Install vapor elbow with equalizer adapter to vapor line of
line set and vapor connection to indoor coil. Adapter has a
1/4-in. male connector for attaching equalizer tube.
14. Connect equalizer tube of TXV to 1/4-in. equalizer fitting
on vapor line adapter. Use backup wrench to prevent
damage to equalizer fitting.
15. Proceed with remainder of unit installation.
CAUTION:
Remove indoor coil piston if unit is to be
installed on system with a TXV metering device.
VII.
MAKING PIPING CONNECTIONS
WARNING:
Relieve pressure and recover all refrigerant
before system repair or final unit disposal to avoid
personal injury or death. Use all service ports and open all
flow-control devices, including solenoid valves.
CAUTION:
Do not leave system open to atmosphere
any longer than minimum required for installation. POE
oil in compressor is extremely susceptible to moisture
absorption. Always keep ends of tubing sealed during
installation.
CAUTION:
If ANY refrigerant tubing is buried, provide
a 6 in. vertical rise at service valve. Refrigerant tubing
lengths up to 36 in. may be buried without further special
consideration. Do not bury lines over 36 in.
CAUTION:
To prevent damage to unit or service valves
observe the following:
• Use a brazing shield
• Wrap service valves with wet cloth or use a heat sink
material.
Outdoor units may be connected to indoor section using accessory
tubing package or field-supplied refrigerant grade tubing of correct
size and condition. For tubing requirements beyond 50 ft, substan-
tial capacity and performance losses can occur. Following the
Fig. 4—Check-Flo-Rater® Components (533A Use)
A01164
PISTON
TEFLON SEAL
PISTON RETAINER
13
⁄
16
–IN.
BRASS HEX
NUT
3
⁄
4
–IN. BRASS
HEX BODY
STRAINER
DISTRIBUTOR
COPPER TUBE
PISTON
RING
—3—
