And Replacement - Carrier FA4ANF Service Manual

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.
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 either
a tubing cutter to cut tubes or a torch to unbraze tubes as
required.
NOTE: If a torch is used to unbraze line set, protect fitting panel
with a wet cloth or braze shield, as necessary. System contains oil
vapors which may ignite when exposed to a flame.
5. Remove coil access and fitting panels.
6. Remove 1 screw securing coil to unit casing.
7. Remove coil/pan assembly from unit.
8. Place assembly on a flat surface. Remove 2 screws securing
coil support columns to pan. (See Fig. 32.)
9. Rotate columns 90°, pull away from coil, and remove columns
from assembly.
10. Remove remaining 2 screws securing coil to condensate pan.
11. Remove coil from condensate pan.
12. Remove coil top seal. (See Fig. 32.)
13. Install new coil into condensate pan using 2 original screws
and 2 support columns.
NOTE: Correct coil position in condensate pan is essential to
reliable operation.
COIL MOUNTING
SCREW
COIL
SUPPORT
RAIL
SLOPE
COIL
SKI
DRAINPAN
REFRIGERANT
CONNECTIONS
Fig. 32—Slope Coil Component Location
COIL TO
PAN SCREW
(BOTH SIDES)
A98113
14. Install new coil/pan assembly into unit. Secure with 2 screws
previously removed from unit casing.
15. Reinstall coil access and fitting panels.
16. Reconnect liquid and vapor refrigerant tubes, and condensate
drain tube. Install new liquid line filter-drier.
17. Evacuate tube set and indoor coil to 500 microns, back seat
(open) liquid and vapor service valves.
18. Turn on electrical supplies to indoor and outdoor units.
19. Check system refrigerant charge and operation. See "Split-
System Residential Air Conditioners and Heat Pumps Service
Manual" for further information.
FX4A AND FV4A COIL/CONDENSATE PAN REMOVAL
AND REPLACEMENT (PURON REFRIGERANT)
Step 1—A-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.
c. Start unit in cooling mode.
d. Run unit until low pressure switch opens at 50 psig
(350kPa) or vapor pressure reaches 5 psig (35kPa). Do not
allow compressor to pump into a vacuum.
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.)
38