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NOTE
: Once the compressor has started and then has stopped, it
should not be started again until 5 minutes have elapsed.
The cooling cycle remains on until the room temperature drops to
a point that is slightly below the cooling control setting of the room
thermostat. At this point, the thermostat breaks the circuit between
thermostat terminal R to terminals Y and G. These open circuits
deenergize contactor coil C and relay coil TDR. The condenser and
compressor motors stop. After a 30--second delay, the blower motor
stops. The unit is in a standby condition, waiting for the next call for
cooling from the room thermostat.
MAINTENANCE
To ensure continuing high performance, and to minimize the
possibility of premature equipment failure, periodic maintenance
must be performed on this equipment. This cooling unit should be
inspected at least once each year by a qualified service person. To
troubleshoot unit, refer to Table 6, Troubleshooting Chart.
NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.
PERSONAL INJURY AND UNIT DAMAGE HAZARD
Failure to follow this warning could result in personal injury
or death and possible unit component damage.
The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills, tools
and equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment, other than those
procedures recommended in the Owner’s Manual.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow these warnings could result in personal
injury or death:
1. Turn off electrical power to the unit before performing any
maintenance or service on this unit.
2. Use extreme caution when removing panels and parts.
3. Never place anything combustible either on or in contact
with the unit.
!
WARNING
UNIT OPERATION HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Errors made when reconnecting wires may cause improper
and dangerous operation. Label all wires prior to
disconnecting when servicing.
CAUTION
!
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 each
cooling season for cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness each cooling
season. Clean when necessary.
4. Check electrical connections for tightness and controls for
proper operation each cooling season. Service when
necessary.
5. Ensure electric wires are not in contact with refrigerant
tubing or sharp metal edges.
AIR FILTER
IMPORTANT
: 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 Table 1 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 cooling season and twice during the heating season, or
whenever the filter becomes clogged with dust and lint.
INDOOR BLOWER AND MOTOR
NOTE
: All motors are pre--lubricated. 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
and lubricating the blower motor and wheel.
!
WARNING
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
housing, 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
attachment. 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 cooling
cycles.
50SD