ELECTRICAL CONTROLS AND WIRING
Inspect and check the electrical controls and wiring annually. Be
sure to turn off the electrical power to the unit and install lockout
tag.
Remove access panel to locate all the electrical controls and
wiring. Check all electrical connections for tightness. Tighten all
screw connections. If any smoky or burned connections are
noticed, disassemble the connection, clean all the parts, restrip the
wire end and reassemble the connection properly and securely.
After inspecting the electrical controls and wiring, replace the
access panel. Start the unit, and observe at least one complete
heating cycle and one complete cooling cycle to ensure proper
operation. If discrepancies are observed in either or both operating
cycles, or if a suspected malfunction has occurred, check each
electrical component with the proper electrical instrumentation.
Refer to the unit wiring label when making these checkouts.
NOTE:
Refer to the heating and/or cooling sequence of operation
in this publication as an aid in determining proper control
operation
REFRIGERANT CIRCUIT
Inspect all refrigerant tubing connections and the unit base for oil
accumulations annually. Detecting oil generally indicates a refrig-
erant leak.
System under pressure. Relieve pressure and recover all
refrigerant before system repair or final unit disposal to avoid
personal injury or death. Use all service ports and open all
flow-control devices, including solenoid valves.
If oil is detected or if low cooling performance is suspected,
leak-test all refrigerant tubing using an electronic leak-detector,
halide torch, or liquid-soap solution. If a refrigerant leak is
detected, refer to Check for Refrigerant Leaks section.
If no refrigerant leaks are found and low cooling performance is
suspected, refer to Checking and Adjusting Refrigerant Charge
section.
EVAPORATOR AIRFLOW
The heating and/or cooling air-flow 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.
METERING DEVICE — ACUTROL DEVICE
This metering device is a fixed orifice and is located in the header
to the evaporator coil.
LIQUID LINE STRAINER
The liquid line strainer (to protect metering device) is made of wire
mesh and located in the liquid line on the inlet side of the metering
device.
TROUBLESHOOTING
Use the Troubleshooting–Cooling guide (see Table 10) if problems
occur with these units.
START-UP CHECKLIST
Use the Start-Up checklist to ensure proper start-up procedures are
followed.
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