Carrier 48KHA - Manual (Page 19)

on motor shaft by loosening setscrew(s), then moving blade
assembly up. Be sure setscrew(s) is on flat(s) of shaft before
tightening.
Electrical Controls and Wiring— Inspect and check electri­
cal controls and wiring annually. Be sure to turn off gas sup­
ply and then electrical power to unit.
Remove control, blower and compressor compartment
access panels to locate all 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 parts, restrip
wire end and reassemble connection properly emd securely.
After inspecting electrical controls and wiring, replace all
panels. Start unit and observe at least one complete beating
cycle and one complete cooling cycle to ensure proper opera­
tion. If discrepancies are observed in either or both operat­
ing cycles, or if a suspected malfunction has occurred, check
each electrical component with proper electrical instrumen­
tation. Refer to unit wiring label when making these
checkouts.
NOTE: Refer to heating and/or cooling sequence of opera­
tion in this publication as an aid in determining proper con­
trol operation.
Refrigerant Circuit— Annually inspect all refrigerant tubing
connections and unit base for oil accumulations. Presence of
oil generally indicates a refrigerant leak.
If oil is detected or if low-cooling performance is suspected,
leeik-test all refrigerant tubing using em electronic leak
detector, hedide torch, or liquid-soap solution. If a refriger­
ant leak is detected, see Unit Preparation—Refrigerant
Leeiks.
If no refrigerant leaks are found and low-cooling perform­
ance is suspected, see Cooling Section Start-Up emd Adjust­
ments—Checking and Adjusting Refrigerant Charge
section.
Gas Input— Gas input does not inquire checking unless
improper heating performance is suspected. If a problem
exists, refer to Heating Section Start-Up and Adjustments
section.
Evaporator Airflow— Heating and/or cooling airflow does
not require checking unless improper performance is sus­
pected.
If a problem exists, be sure all supply- and retum-air
grilles are open and free from obstructions, and air filter is
clean.
When necessary, refer to Cooling Section Start-Up
and Adjustments Indoor Airflow and Airflow Adjustments
section to check system eiirflow.
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