E. Operating Modes ; All installations and services must be performed by qualified service personnel.- Page 6

All installations and services must be performed by qualified service personnel.

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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 "EAC".  In this application, the humidifier will operate on any blower operation. Humidifier 
should be controlled by humidistat to prevent operation during cooling fan operation. 

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.   

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 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 LOW column of the CFM Tables. 

Anti-Short Cycle Operation 

To prevent compressor short cycling,  a call for cooling will be ignored for four minutes after the 
termination of any cooling call.  The anti-short cycle delay is also in effect at power-up.