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EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in unit component
damage.
Errors made when reconnecting wires may cause improper
and dangerous operation. Label all wires prior to disconnec-
tion when servicing.
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect indoor coil, drain pan, and condensate drain at least
each cooling season for cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness and check
lubrication each heating and cooling season. Clean when
necessary.
4. Check electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
when necessary.
5. Ensure electric wires are not in contact with refrigerant tubing
or sharp metal edges.
AIR FILTER
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in unit component
damage.
Never operate the unit without a suitable air filter in the
return-air duct system. Always replace the filter with the same
dimensional size and type as originally installed. See Tables
1 and 2 for recommended filter sizes.
Inspect air filter(s) at least once each month and replace
(throwaway-type) or clean (cleanable-type) at least twice during
each heating and cooling season or whenever the filter(s) becomes
clogged with dust and lint.
EVAPORATOR BLOWER AND MOTOR
NOTE:
All motors are prelubricated. Do not attempt to lubricate
these motors.
For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Disconnect and tag electrical power to the unit before
cleaning the blower motor and wheel.
To clean the blower motor and wheel:
1. Remove and disassemble blower assembly as follows:
a. Remove unit access panel.
b. Disconnect motor lead from time delay relay (TDR).
Disconnect yellow lead from terminal L2 of the contactor.
c. On all units remove blower assembly from unit. Remove
screws securing blower to blower partition and slide
assembly out. Be careful not to tear insulation in blower
compartment.
d. Ensure proper reassembly by marking blower wheel and
motor in relation to blower housing before disassembly.
e. Loosen setscrew(s) that secures wheel to motor shaft,
remove screws that secure motor mount brackets to hous-
ing, and slide motor and motor mount out of housing.
2. Remove and clean blower wheel as follows:
a. Ensure proper reassembly by marking wheel orientation.
b. Lift wheel from housing. When handling and/or cleaning
blower wheel, be sure not to disturb balance weights (clips)
on blower wheel vanes.
c. Remove caked-on dirt from wheel and housing with a
brush. Remove lint and/or dirt accumulations from wheel
and housing with vacuum cleaner, using soft brush attach-
ment. Remove grease and oil with mild solvent.
d. Reassemble wheel into housing.
e. Reassemble motor into housing. Be sure setscrews are
tightened on motor shaft flats and not on round part of
shaft.
f. Reinstall unit access panel.
3. Restore electrical power to unit. Start unit and check for
proper blower rotation and motor speeds during heating and
cooling cycles.
CONDENSER COIL, EVAPORATOR COIL, AND CONDEN-
SATE DRAIN PAN
Inspect the condenser coil, evaporator coil, and condensate drain
pan at least once each year.
The coils are easily cleaned when dry; therefore, inspect and clean
the coils either before or after each cooling season. Remove all
obstructions, including weeds and shrubs, that interfere with the
airflow through the condenser coil.
Straighten bent fins with a fin comb. If coated with dirt or lint,
clean the coils with a vacuum cleaner, using the soft brush
attachment. Be careful not to bend the fins. If coated with oil or
grease, clean the coils with a mild detergent-and-water solution.
Rinse coils with clear water, using a garden hose. Be careful not to
splash water on motors, insulation, wiring, or air filter(s). For best
results, spray condenser coil fins from inside to outside the unit.
On units with an outer and inner condenser coil, be sure to clean
between the coils. Be sure to flush all dirt and debris from the unit
base.
Inspect the drain pan and condensate drain line when inspecting
the coils. Clean the drain pan and condensate drain by removing all
foreign matter from the pan. Flush the pan and drain tube with
clear water. Do not splash water on the insulation, motor, wiring,
or air filter(s). If the drain tube is restricted, clear it with a
“plumbers snake” or similar probe device. Ensure that the auxiliary
drain port above the drain tube is also clear
CONDENSER FAN
UNIT OPERATIONAL HAZARD
Failure to follow this caution may result in damage to unit
components.
Keep the condenser fan free from all obstructions to ensure
proper cooling operation. Never place articles on top of the
unit.
1. Remove 6 screws holding condenser grille and motor to top
cover.
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