Thermo Pride OD6FA072D48, Installation, Operation And Service Manual

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Operational 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 operate the fan relay and power the “Low” blower speed
terminal. 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 precedence after their
respective turn-on time delays have expired.
Cooling Mode

NRG Max Control - A call for cool (“Y”) is received from the thermostat. If the heat
mode is not active the “COOL” speed blower terminal is energized. When the call
for cool is satisfied, the “COOL” speed blower terminal is de-energized, the
“HEAT” speed blower is energized and the blower off delay of 45 seconds is
started. Forty-five seconds later the “HEAT” speed blower terminal is de-
energized.

UT Control Board - 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 and after a 10 second power demand conservation
delay energizes the “COOL” speed blower terminal. 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 “COOL” speed blower terminal is de-
energized. To prevent compressor short cycling, a call for cooling will be ignored
for four minutes after the termination of any cooling call or at control power up.
Dehumidification Operation
If a call for dehumidification is received while the Cool Mode is active, blower speeds will
be reduced. The “COOL” blower speed terminal will be de-energized and “Heat” blower
speed (NRG Max Control) or “Low” (UT Control) will be energized.
EAC (electronic air cleaner)
If a call for fan (“G”), cool (“Y”) or heat (“W”) is received from the thermostat, the “EAC”
terminal is energized whenever the blower is energized to power an electronic fan
cleaner.