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Thermostat Operation − Thermostat Operation
Though your thermostat may vary somewhat from the de-
scription below, its operation will be similar.
Temperature Setting Levers
Most heat pump thermostats have two temperature selec-
tor levers: one for heating and one for cooling. Set the lev-
ers or dials to the desired temperature setpoints for both
heating and cooling. Avoid frequent temperature adjust-
ment; turning the unit off and back on before pressures
equalize puts stress on the unit compressor.
Fan Switch
In AUTO or INT (intermittent) mode, the blower operates
only when the thermostat calls for heating or cooling. This
mode is generally preferred when humidity control is a
priority. The ON or CONT mode provides continuous in-
door blower operation, regardless of whether the com-
pressor or auxiliary heat are operating. This mode is re-
quired when constant air circulation or filtering is desired.
System Switch
Set the system switch for heating, cooling or auto opera-
tion. The auto mode allows the heat pump to automatically
switch from heating mode to cooling mode to maintain pre-
determined comfort settings. Many heat pump thermo-
stats are also equipped with an emergency heat mode
which locks out heat pump operation and provides tempo-
rary heat supplied by the auxiliary heat.
Indicating Light
Most heat pump thermostats have an amber light which in-
dicates when the heat pump is operating in the emergency
heat mode.
Temperature Indicator
The temperature indicator displays the actual room tem-
perature.
Programmable Thermostats
Your Lennox system may be controlled by a program-
mable thermostat. These thermostats provide the added
feature of programmable time-of-day setpoints for both
heating and cooling. Refer to the user’s information manu-
al provided with your particular thermostat for operation
details.
Preservice Check
If your system fails to operate, check the following before
calling for service:
Check to see that all electrical disconnect switches are
ON.
Make sure the room thermostat temperature selector
is properly set.
Make sure the room thermostat system switch is prop-
erly set.
Replace any blown fuses, or reset circuit breakers.
Make sure unit access panels are in place.
Make sure air filter is clean.
Locate unit model number and have it handy before
calling.
