4
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
R
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
!
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
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. 4 for correct positioning of
sensing bulb.
9. Proceed with remainder of unit installation.
2 O'CLOCK
10 O'CLOCK
SENSING BULB
STRAP
SUCTION TUBE
8 O'CLOCK
4 O'CLOCK
7
⁄
8
IN. OD & SMALLER
LARGER THAN
7
⁄
8
IN. OD
A81032
Fig. 4
---
Position of Sensing Bulb
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.
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. 4 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.
A05226
Fig. 5
---
Liquid Service Valve with Sweat Adapter Tube
25H
C
A