Allied Air 4HP16LT Series Installation And Maintenance Instructions Manual page 27

adjustment; turning the unit off and back on before
pressures equalize puts stress on 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 indoor
blower operation, regardless of whether the compressor or
auxiliary heat are operating. This mode is required 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
predetermined comfort settings. Many heat pump thermo-
stats are also equipped with an emergency heat mode
which locks out heat pump operation and provides
temporary heat supplied by the auxiliary heat.
Indicating Light
Most heat pump thermostats have an amber light which
indicates when the heat pump is operating in the emer-
gency heat mode.
Temperature Indicator
The temperature indicator displays the actual room
temperature.
Programmable Thermostats
Your system may be controlled by a programmable thermo-
stat. These thermostats provide the added feature of
programmable time-of-day setpoints for both heating and
cooling. Refer to the user's information manual provided
with your particular thermostat for operation details.
Page 27
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 thermostat temperature selector is
properly set.
• Make sure the thermostat system switch is properly 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.
Issue 1004 506468-01