Overload; Checking Compressor Efficiency; Filter Drier Replacement - Amana PTAC Service Instructions Manual

SERVICING
2. Carefully apply line voltage.
a. If the compressor starts and continues run, the cause
for failure is somewhere else in the system.
b. If the motor fails to start - replace.
Since all single phase compressors are of the permanent
split capacitor design the high and low side pressure must
be approximately equal or the low torque compressor may
not start.
S-17A OVERLOAD
Each compressor is equipped with an internal overload.
The line break internal overload senses both motor amper-
age and winding temperature. High motor temperature or
amperage heats the disc causing it to open, breaking the
common circuit within the compressor.
Fuse, circuit breaker, ground fault protective device, etc.
has not tripped.
1. With no power to the unit, remove the compressor cover,
and overload lead from the compressor terminal.
2. Using an ohmmeter: Test continuity between terminals
of the overload. If not continuous, the overload is open,
replace the overload.
S-104 CHECKING COMPRESSOR EFFICIENCY
The reason for compressor inefficiency is broken or dam-
aged suction and/or discharge valves, or scroll flanks on
Scroll compressors, reducing the ability of the compressor
to pump refrigerant vapor.
The condition of the valves or scroll flanks is checked in the
following manner.
1. Attach gauges to the high and low side of the system.
2. Start the system and run a "Cooling Performance Test.
If the test shows:
a. Below normal high side pressure.
b. Above normal low side pressure.
c. Low temperature difference across coil.
d. Low amp draw at compressor.
and the charge is correct. The compressor is faulty - re-
place the compressor. NOTE: THIS TEST CANNOT BE DONE
IN THE HEATING MODE.
S-116 FILTER DRIER REPLACEMENT
WARNING
1. Remove the two screws securing the front. Not all in-
stallations have the screws. Then remove the front. Do
this by pulling the bottom corners out and lifting up.
Front Mounting Screw
accessed
through louvers.
2. Remove the six screws securing the unit to the wall
sleeve. If screws are not present they should be installed
when units is reinstalled.
3. Pull unit from wall sleeve and take unit to adequate work
area. Taking care not to spill any condensate which may
still be in the basepan.
IMPORTANT NOTE: Effective July 1,1992. Before opening
any refrigerant system it is the responsibility of the service
technician to capture the refrigerant for safe disposal.
4. After all the refrigerant has been recovered from the
system, remove bottom of strainer by unbrazing the
strainer from the condenser elbow. Hold the strainer
with a pair of pliers while heating up the brazed joint
with a torch. When joint is hot pull up on strainer and
remove.
Heat up Capillary tube and remove from line.
5. To install the new filter drier assembly, remove the end
plugs and clean the ends to be brazed into place.
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