Step 6—Check Indoor Expansion Device
For proper unit operation and reliability, units must be
installed with factory-supplied balance port hard shutoff TXV
specifically designed to operate with Puron® two-speed unit.
Do not install with evaporator coils having capillary tube
metering devices.
FURNACE COILS
Remove existing AccuRater® piston from indoor coil and install
factory-supplied TXV.
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. A factory-supplied or
approved filter drier must be installed in the liquid line.
Install TXV kit to indoor coil as follows:
Installing TXV in Place of Piston
1. Ensure coil has not been exposed to refrigerant pressure.
2. Remove indoor coil inlet tube at piston body inlet. Use
back-up wrench to prevent damage.
3. Remove piston retainer, being careful not to damage sealing
surface of O-ring.
4. Remove and discard factory-installed piston. (Replace retainer
if O-ring is damaged.)
5. Reinstall piston retainer in piston body.
6. Replace indoor coil inlet tube. Use back-up wrench to prevent
damage.
To prevent damage to the unit, use a brazing shield and wrap
TXV with wet cloth.
7. Sweat swivel adapter (See Fig. 6D) to inlet of indoor coil and
attach to TXV (See Fig. 6A) 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.
8. Install vapor elbow (See Fig. 6B) with equalizer adapter to
suction tube of line set and suction connection to indoor coil.
Adapter has a 1/4-in. male flare connector for attaching
equalizer tube.
9. Connect equalizer tube of TXV to 1/4-in. equalizer fitting on
vapor line adapter.
10. Attach TXV bulb to horizontal section of suction line using
bulb strap provided. (See Fig. 6C.) Insulate bulb with factory-
supplied insulation tape (See Fig. 6E). See Fig. 7 for correct
positioning of sensing bulb.
11. Proceed with remainder of unit installation.
FAN COILS
Indoor unit (fan coil) does NOT contain a balance port hard
shut-off TXV specifically designed for Puron® two-speed TXV.
Changeout is required.
Replacing R-22 TXV or Non-Balance Port Puron® TXV on
Indoor Coil
1. Pump system down to 2 psig and recover refrigerant.
2. Remove coil access panel and fitting door from cabinet.
3. Remove and save TXV support clamp using a 5/16-in. nut
driver.
4. Remove 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.
7. Braze equalizer stub-tube closed. Use protective barrier as
necessary to prevent damage to drain pan.
IMPORTANT:
Route the equalizer tube of approved factory
supplied Puron® TXV through suction line connection opening in
fitting door prior to replacing fitting panel around tubing.
8. Install TXV (Fig. 6A) with 3/8-in. copper inlet tube through
small hole in service panel. Use wrench and backup wrench,
to avoid damage to tubing valve.
9. Reinstall TXV support clamp (removed in item 3).
10. Attach TXV bulb to vapor tube inside cabinet in same location
as original was removed from using supplied bulb strap (See
Fig. 6C). Insulate bulb with factory-supplied insulation tape
(See Fig. 6E). See Fig. 7 for correct positioning of sensing
bulb.
Fig. 5—TXV Installed
A91277
THERMOSTATIC
EXPANSION
VALVE
EQUALIZER
TUBE
SENSING
BULB
COIL
Fig. 6—TXV Kit Contents
A01418
A
B
D
INLET
COIL
E
BULB
INSULATION
TAPE
C
3
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