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System Operation
The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch
is in the
ON
position, the indoor blower operates
continuously.
HIGH PRESSURE SWITCH
This model is equipped with a auto-reset high pressure
switch (single−pole, single−throw) which is located on the
liquid line. The switch shuts off the compressor when
discharge pressure rises above the factory setting.
High
Pressure
(auto reset) − trip at 590 psig, reset at 418 psig.
Maintenance
WARNING
Electric shock hazard. Can cause injury or death.
Before attempting to perform any service or
maintenance, turn the electrical power to unit OFF at
disconnect switch(es). Unit may have multiple power
supplies.
WARNING
Improper installation, adjustment, alteration, service or maintenance can
cause personal injury, loss of life, or damage to property.
Installation and service must be performed by a licensed professional
installer (or equivalent) or a service agency.
Maintenance and service must be performed by a qualified
installer or service agency. At the beginning of each
cooling season, the system should be checked as follows:
Outdoor Unit
1. Outdoor unit fan motor is pre−lubricated and sealed.
No further lubrication is needed.
2. Visually inspect all connecting lines, joints and coils for
evidence of oil leaks.
3. Check all wiring for loose connections.
4. Check for correct voltage at unit (unit operating).
5. Check amp draw on outdoor fan motor.
Motor
Nameplate
:_________
Actual
:__________.
6. Inspect drain holes in coil compartment base and
clean if necessary.
NOTE - If insufficient cooling occurs, the unit should be
gauged and refrigerant charge should be checked.
Outdoor Coil
Clean and inspect outdoor coil (may be flushed with a
water hose). Ensure power is off before cleaning.
NOTE It may be necessary to flush the outdoor coil
more frequently if it is exposed to substances which are
corrosive or which block airflow across the coil (e.g., pet
urine, cottonwood seeds, fertilizers, fluids that may contain
high levels of corrosive chemicals such as salts)
Sea Coast
Moist air in ocean locations can carry salt,
which is corrosive to most metal. Units that are located
near the ocean require frequent inspections and
maintenance. These inspections will determine the
necessary need to wash the unit including the outdoor coil.
Consult your installing contractor for proper
intervals/procedures for your geographic area or service
contract.
Indoor Unit
1. Clean or change filters.
2. Lennox blower motors are prelubricated and
permanently sealed. No more lubrication is needed.
3. Adjust blower speed for cooling. Measure the pressure
drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.
4.
Belt Drive Blowers −
Check belt for wear and proper
tension.
5. Check all wiring for loose connections.
6. Check for correct voltage at unit. (blower operating)
7. Check amp draw on blower motor.
Motor
Nameplate
:_________
Actual
:__________.
Indoor Coil
1. Clean coil if necessary.
2. Check connecting lines, joints and coil for evidence of
oil leaks.
3. Check condensate line and clean if necessary.
