Remove indoor coil piston if unit is to be installed on system
with a TXV metering device.
IMPORTANT:
The TXV should be mounted as close to the
indoor coil as possible and in a vertical, upright position. Avoid
mounting the inlet tube vertically down. Valve is more susceptible
to malfunction due to debris if inlet tube is facing down. A factory
approved filter-drier must be installed in the liquid line.
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.
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 insulation
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 connec-
tions 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.
7. Braze equalizer stub-tube closed. Use protective barrier as
necessary to prevent damage to drain pan.
IMPORTANT:
Route the equalizer tube of Puron® TXV through
suction line connection opening in fitting panel prior to replacing
fitting panel around tubing.
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.
Remove indoor coil piston if unit is to be installed on system
with a TXV metering device.
Step 7—Making Piping Connections
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.
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.
Fig. 4—AccuRater® Components (38EZA 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
