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After inspecting the electrical controls and wiring, replace all the
panels. Start the unit, and observe at least one complete cooling
cycle to ensure proper operation. If discrepancies are observed in
operating cycle, or if a suspected malfunction has occurred, check
each electrical component with the proper electrical instrumenta-
tion. Refer to the unit wiring label when making these checkouts.
NOTE:
Refer to the Sequence of Operation section, as an aid in
determining proper control operation.
Step 7—Refrigerant Circuit
Inspect all refrigerant tubing connections and the unit base for oil
accumulations annually. Detecting oil generally indicates a refrig-
erant leak.
If oil is detected or if low cooling performance is suspected,
leak-test all refrigerant tubing using an electronic leak-detector, or
liquid-soap solution. If a refrigerant leak is detected, refer to Check
for Refrigerant Leaks section. (See Table of Contents for page
number.)
If no refrigerant leaks are found and low cooling performance is
suspected, refer to Refrigerant Charge. (See Table of Contents for
page number.)
Step 8—Indoor Airflow
The cooling airflow does not require checking unless improper
performance is suspected.
If a problem exists, be sure that all
supply- and return-air grilles are open and free from obstructions,
and that the air filter is clean
. When necessary, refer to Indoor
Airflow and Airflow Adjustments section to check the system
airflow.
Step 9—Metering Devices
Refrigerant cooling metering device is an Accurator (024-042) or
TXV (048 and 060) located upstream of the indoor coil distributor
assembly. Refrigerant heating mode metering device is an Accu-
rater located upstrem of the outdoor coil distributor assembly.
Step 10—Lubrication
COMPRESSOR
—The compressor is charged with the correct
amount of oil at the factory.
FAN MOTOR BEARINGS
—Fan motor bearings are perma-
nently lubricated. No further lubrication of outdoor or indoor fan
motors is required.
Step 11—Liquid Line Strainer
The liquid line strainer (to protect metering device) is made of wire
mesh and is located in the liquid line on the inlet side of the
metering device.
Check valves are also located in the liquid lines near the strainers.
The Strainers are the larger of the two components.
Step 12—High Flow Valves
Located on the compressor hot gas and suction tubes are High
Flow Valves. Large black plastic caps distinguish these valves
with O-rings located inside the caps. These valves cannot be
accessed for service in the field. Ensure the plastic caps are in
place and tight or the possibility of refrigerant leakage could occur.
TROUBLESHOOTING
Use the Troubleshooting Cooling and Heating guide if problems
occur with these units.
START-UP CHECKLIST
Use the Start-Up checklist to ensure proper start-up procedures are
followed.
Fig. 13—Outdoor-Fan Adjustment (060 Size)
C02017
0.708in.
17