Liquid Tube Strainer; Fa, Fb, Fc, Fk Coil/Condensate Pan Removal And Replacement; A-Coil Units; Slope Coil Units - Carrier FA4ANF Service Manual

7. Replace seal ring on retainer.
8. Reconnect refrigerant tube to piston body.
9. Pressurize tubing and coil, then leak check.
10. Evacuate tubing and coil as necessary.
Use a backup wrench and do not over tighten, as deformation
of the piston body will occur, causing the piston to lodge in
a partially open or closed position.

LIQUID TUBE STRAINER

The TXV and refrigerant flow-control device is protected on the
indoor coil by a wire mesh strainer. It is located inside the 3/8-in.
liquid tube at field braze joint just outside unit casing. Access to
strainer is through field braze joint.
FA, FB, FC, FK COIL/CONDENSATE PAN REMOVAL
AND REPLACEMENT
Step 1—A-Coil Units
HORIZONTAL
CONDENSATE
PAN
HORIZONTAL
PAN CLIP
COIL BRACKET
SCREWS–
(4 PER UNIT)
DELTA PLATE TO
PAN (4 PER UNIT)
Fig. 31—A-Coil Component Location
If it is determined that system does not have leaks and refrigerant
is not contaminated, proceed as follows:
1. Recover system refrigerant.
a. Attach manifold/gage set to service valves.
b. Front seat (close) liquid tube service valve.
c. Start unit in cooling mode.
d. Run unit until low pressure switch opens at 27 psig or
vapor pressure reaches 5 psig (35kPa). Do not allow
compressor to pump into a vacuum.
EXPANSION DEVICE
(TXV SHOWN)
COIL TOP SEAL
DELTA PLATE
VERTICAL
CONDENSATE
PAN
A90268
e. Turn off electrical supply to outdoor unit.
f. Front seat vapor service valve.
g. Recover any remaining refrigerant.
NOTE: All outdoor unit coils will hold only factory-supplied
amount of refrigerant. Excess refrigerant, such as in long-tube
applications, may cause compressor internal pressure relief valve
to open (indicated by sudden rise in vapor pressure) before vapor
pressure reaches 5 psig (35kPa). If this occurs, turn off electrical
supply to outdoor unit immediately, front seat vapor service valve,
and recover any remaining refrigerant.
2. Turn off electrical supply to indoor unit.
3. Disconnect condensate drain tube.
4. Disconnect liquid and vapor tubes from indoor coil. Use a
tubing cutter to cut tubes.
NOTE: If a torch is used to unbraze tube set, protect fitting panel
with a wet cloth or braze shield, as necessary.
5. Remove coil access panel.
6. Remove clip securing fitting panel to condensate drain pan.
Remove fitting panel.
7. Remove any shipping clips, including horizontal pan clip, and
slide coil/condensate pan assembly out of unit.
8. Upflow or Horizontal Applications Only—Remove hori-
zontal condensate drain pan from coil/condensate pan assem-
bly. (See Fig. 31.)
9. Remove 4 coil brackets. (See Fig. 31.)
10. Remove screws at delta plates and remove coil from vertical
condensate drain pan. (See Fig. 31.)
11. Horizontal Applications Only—Remove coil top seal (at-
tached with 4 screws) and J-shaped tube from original coil and
install it in same position on new coil. (See Fig. 31.)
12. Place coil assembly in plastic condensate pan and secure using
4 screws through delta plate. (See Fig. 31.)
13. Horizontal and Upflow Applications Only—Attach 4 coil
brackets to coil/pan assembly. (See Fig. 31.)
14. Horizontal Applications only—Place horizontal condensate
pan into position on coil/pan assembly.
NOTE: Installation of horizontal condensate pan is not necessary
for upflow or downflow applications.
15. Slide complete assembly into unit.
16. Reinstall fitting panel and reconnect clip securing fitting panel
to condensate drain pan.
17. Horizontal Applications Only—Reinstall horizontal pan
clip. Secure with 1 screw. (See Fig. 31.)
18. Reinstall coil access panel.
19. Reconnect liquid and vapor refrigerant tubes, and condensate
drain tube. Install new liquid line filter-drier.
20. Evacuate tube set and indoor coil to 500 microns, back seat
(open) liquid and vapor service valves.
21. Turn on electrical supplies to indoor and outdoor units.
22. Check system refrigerant charge and operation. See "Split-
System Residential Air Conditioners and Heat Pumps Service
Manual" for further information.
Step 2—Slope Coil Units
If it is determined that system does not have leaks and refrigerant
is not contaminated, proceed as follows:
1. Recover system refrigerant.
a. Attach manifold/gage set to service valves.
b. Front seat (close) liquid tube service valve.
37