Installation guide

SEQUENCE OF OPERATION
A, COOLING MODE B, HEATING MODE
On a call for cooling, the thermostat makes circuits R-O,
R-Y, and R-G. Circuit R-O energizes reversing valve,
switching it to cooling position. Circuit R-Y energizes con-
tactor, starting outdoor fan motor and compressor. Circuit
R-G energizes indoor unit blower relay, starting indoor
blower motor.
When thermostat is satisfied, its contacts open,
de-energizing contactor and blower relay. Compressor
and motors stop.
NOTE: If indoor unit is equipped with a time-delay relay
circuit, the blower runs an additional length of time to in-
crease system efficiency. (Applies to both cooling and
heating modes.)
On a call for heating, the thermostat makes circuits R-Y
and R-G (circuit R-O is NOT made, and the reversing
valve stays in the de-energized, heating position). Circuit
R-Y energizes contactor, starting outdoor fan motor and
compressor. Circuit R-G energizes indoor blower relay,
starting blower motor. If the room temperature continues
to fall, circuit R-W2 is made through the second-stage
room thermostat bulb. Circuit R-W2 energizes a se-
quencer, bringing on the first bank supplemental electric
heat and providing electrical potential to the second heat-
er sequencer (if used). If outdoor temperature falls below
the setting of the outdoor thermostat (field-installed op-
tion), contacts close to complete the circuit and bring on
the second bank of supplemental electric heat.
When the thermostat is satisfied, its contacts open, de-
energizing contactor, blower relay, and sequencer.
Compressor, motors, and heaters stop.
TROUBLESHOOTING
Some models are factory equipped with the Comfort
Alert'H Diagnostics device in the control box (refer to Fig-
ure 16). Comfort Alert provides around-the-clock
monitoring for common electrical problems, compressor
defects, and broad system faults. If trouble is detected, an
alert code is displayed with a flashing LED indicator. Alert
codes are listed in Figure 17.
The device is factory wired and requires no modifica-
tion, Low voltage lead wires are provided in the control
box for connection to thermostat wires (use wire nuts).
The Comfort Alert device operates by monitoring the
compressor power leads and the thermostat demand sig-
nal (Y terminal). It draws constant 24 VAC power at the R
and C terminals.
Comfort Alert TM Diagnostics
Figure 16
(some models)
Compressor Wires
Pass Through Holes (3)
, Thermostat Demand
24 VAC Hot
MAINTENANCE
Condensate Drain
During the cooling season, check monthly for free flow of
drainage and clean if necessary.
Cleanliness
These tips will help keep the air conditioner looking better
and working more efficiently:
1. Free flow of air is essential. Keep fences, shrubs,
trash cans, and other obstructions at least 18 inch-
es from all coil inlets.
2. Keep the coil free of grass clippings, leaves,
weeds, and other debris.
NOTE: Coil may occasionally require cleaning with
a liquid solution. The coil must be cold when clean-
ing. Use an alkaline based cleaner only. Cleaning a
hot coil or using an acid based cleaner will remove
the paint from the fins and may clog the coil.
3. Never use a weather cover over the outdoor unit
unless it is a ventilated type or made of breathable
fabric that will allow moisture to evaporate rapidly.
A cover that holds moisture in the unit will cause
more rust build-up and damage than normal expo-
sure to weather.
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