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All installations and services must be performed by qualified service personnel.
Compressor contactor
The control provides switched 24VAC to operate a compressor contactor. Rating shall be class
2 - 24 VAC pilot duty @ 24 VAC (< 200mA).
EAC (electronic air cleaner)
The control provides a 120VAC output for an electronic air cleaner. This output is energized
whenever the fan motor is energized (either low, heat or cool speed). Connection is made via male
quick connect terminal labeled "EAC".
Humidifier
The control provides a 120 VAC output for a humidifier. Connections are made to a male quick
connect terminal labeled "FAN".
Status LED
A red LED is provided to indicate any thermostat input has been recognized by the microprocessor
on the control. See Diagnostic Features for a function description of operation.
Thermostat Input LEDs
Four green LEDs are placed beneath their respective thermostat connections (W, Y, G and DEHUM)
and operate whenever a call is present. See Diagnostic Features for a function description of
operation.
Motor CFM LED
This green LED will flash once for every 100CFM the blower is producing.
E. Operating Modes
Standby Mode
All outputs are off and the control is waiting for a thermostat demand. The thermostat inputs, and
limit switch are continuously monitored. The control initiates action when a thermostat call is
received or limit switch opens.
Fan Mode
A call for fan ("G") is received from the thermostat. If no other mode is calling for blower operation,
the control will choose a "Low" speed value from the position of DIP switch SW1 positions 4 through
6, as shown in the CFM Tables and operate the fan at that speed. The fan mode will be operated as
long as the "G" input is calling and neither the Heat mode nor the Cool mode is calling for blower
operation. When the Heat and Cool modes call for blower operation, their respective outputs will take
over after their respective turn-on time delays have expired. The speed Output is present until the
fan call is satisfied.
Cooling Mode
A call for cool ("Y") is received from the thermostat. If the heat mode is not active or the anti-short
cycle delay is not in effect, the control will energize the "CC" terminal. After a 10 second delay
blower ramps up to the "COOL" speed determined by the position of DIP switch SW1 (positions 4
through 6) determine a speed as shown in CFM Tables.
When the call for cool is satisfied, the "CC" terminal is de-energized and the cooling off delay of 45
seconds is started. Forty-five seconds later the blower speed ramps toward zero and the control
reverts to Standby Mode.
Dehumidification Operation
If a call for dehumidification is received while the Cool Mode is active, blower speeds will be
reduced. The speed value will be selected from the DEHUM column of the CFM Tables. This input
may only be used on systems using a thermostatic expansion valve (TXV) on the evaporator.
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