Service manual

10
8. THERMOSTAT CONTROL PANEL
A. OPERATION
Your air conditioner is operated from the control panel located
on the electronic wall mounted thermostat. When the furnace
is connected to this thermostat, it will be operated from the
same control panel.
Identification and operational descriptions for all control panel
switches and display are listed below:
1. Liquid Crystal Display - We will start with the display
because the display will be visible any time the
system is in operation. The display will remain visible
while the thermostat is on and powered.
2.
System Switch - The system switch has four
positions to control the operation of the heating and
air conditioning systems. They are as follows:
COOL - When in the cool position, 1
st
and 2
nd
stage
cooling will cycle from the cooling system setpoint.
Blower operation will be controlled by the position
of the Cooling Fan Switch.
HEAT - When in the heat position, the heating
system will cycle from the heating system setpoint.
Heat will be by electricity (heat pump) or gas as
selected on sub-base. The gas heating blower will
operate per the heating system manufacturer
specifications.
OFF - When in the off position, no thermostat or
system operation will occur.
FAN - When in the fan position, the cooling blower
will operate continuously at high speed.
3. Cooling Fan Switch - The fan switch has four
positions from which to control the operation of the
cooling blower. The fan switch controls operation of
the cooling blower only after the system switch is
placed into the COOL position. With the system
switch in any other position, the fan switch will have
no effect on the operation of the cooling blower. Fan
switch positions and their resulting function are
listed below:
HIGH AUTO - When in the high automatic position,
the cooling blower operates at high speed and cycles
off and on with the 1
st
stage compressor. 2
nd
stage
cooling will cycle on and off as needed having no
effect on cooling blower operation.
LOW AUTO - When in the low automatic position,
the cooling blower operates at low speed and cycles
off and on with the 1
st
stage compressor. 2
nd
stage
cooling will cycle on and off as needed having no
effect on cooling blower operation.
LOW ON - When in the low on position, the cooling
blower operates continuously at low speed. Stage 1
and Stage 2 compressors cycle on and off as needed.
HIGH ON - When in the high on position, the
cooling blower operates continuously at high speed.
Stage 1 and Stage 2 compressors cycle on and off as
needed.
During heat pump operation, the blower operates at
high speed with heat demand.