Friedrich VRP12K, Service And Parts Manual

Page: 115 / 221

115 PB
R-410A SEALED SYSTEM REPAIR
Replace The Evaporator Coil 12k/24k
1. Remove unit from closet.
2. Ensure no charge in the system,
evacuating according to
EPA standards.
3. Remove top panel.
4. Remove duct collar.
5. Remove left side upper panel.
NOTE: The 24k units utilize 2 evaporator coils and 2 reheat
coils if applicable. The replacement varies from 12k unit.
Additional panels may need to be removed depending on
which coil or coils are being replaced.
6. Detach 2 thermistors from coil.
7. If Unit has a reheat coil;
Reheat coil can be removed from evaporator coil
by removing 4 screws.
Caution: (reheat coil will need to be supported to
prevent damage to tubing.
Alternatively, the tube to reheat coil can either
be sweateded off and rebrazed or cut and
swedged.
8. Sweat out evaporator coil tubing connections.
9. Remove 3 screws on right hand side end plate.
10. Lift coil up and out and replace evaporator coil in
reverse sequence. Reinstall reheat coil if applicable.
11. Pressurize with a combination of R-410A and nitrogen
and leak test all connections . If a leak cannot be found,
pressurize with a combination of Nitrogen and a trace
charge of R-410A and sweep with with an electronic or
Halide leak detector. Recover refrigerant and repair any
leaks found.
12. If leak detector is unavailable remove all refrigerant
from system and pressurize with nitrogen to 550 psi.
Check that system holds pressure.
Repeat Step 11 to insure no more leaks are present
13. Evacuate the system with a good vacuum pump
capable of a final vacuum of 200 microns or less. The
system should be evacuated through both liquid line
and suction line gauge ports. While the unit is being
evacuated, seal all openings on the defective compressor.
Compressor manufacturers will void warranties on
units received not properly sealed. Do not distort the
manufacturers tube connections.
14. Recharge the system with the correct amount of
refrigerant. The proper refrigerant charge will be found
on the unit rating plate. The use of an accurate measuring
device, such as a charging cylinder, electronic scales or
similar device is necessary.
Figure 504 (12k Evaporator coil)
Figure 505 (24k Evaporator coil)