58
S-104 CHECKING COMPRESSOR EFFICIENCY
The reason for compressor inefficiency is broken or damaged
suction and/or discharge valves, or scroll flanks on Scroll com-
pressors, reducing the ability of the compressor to pump re-
frigerant 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 - replace
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 installa-
tions have the screws. Then remove the front. Do this by
pulling the bottom corners out and lifting up.
2. Remove the six screws securing the unit to the
wall sleeve. If screws are not present they should be in-
stalled 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 techni-
cian 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.
6. Clean the end of the capillary tube and insert into the tube,
it may be necessary to crimp tubing around the capillary
tube, being careful not to damage the capillary tube. Insert
the bottom of the filter drier into the condenser elbow, it
may be necessary to heat slightly to get coupling to go
into place.
Brazing
WARNING
BRAZING REQUIRES HIGH TEMPERATURES. TAKE
PRECAUTION TO PROTECT AGAINST PERSONAL
INJURY OR PROPERTY DAMAGE.
Satisfactory results require cleanliness, experience and the
use of proper material and equipment.
The connections to be brazed must be properly sized, free of
rough edges and clean.
The generally accepted materials are:
•
SIL-FOS
(Alloy of 15% silver, 80% copper, 5% phos-
phorus) is used without flux on copper to copper.
DO
NOT USE FOR A COPPER TO STEEL CONNECTION.
Recommended heat is approximately 1400°F.
•
SILVER SOLDER
(Alloy of 30% silver, 38% copper, 32%
zinc.) Is used with fluoride base flux on copper to steel,
brass to copper, steel to steel, brass to steel. Recom-
mended heat is approximately 1200°F. This is the most
important part of the entire service procedure.
8. Braze coupling and cap tube into place.
SERVICING
