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All installations and services must be performed by qualified service personnel.
The red Board Status LED has two functions:
It will light when the board recognizes a valid input signal and will stay lit until all valid signals
are removed. This is intended to show that the board is functioning and able to respond to input
signals.
It will flash rapidly while 120VAC is missing from the LIMIT switch. This is intended to give a
quick visual indication of the High Limit switch.
Operating Modes for NRGmax board
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
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 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 "COOL" blower speed terminal will be de-energized and "Heat" blower speed 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.
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