Make-Up Air Installation Manual

11/23/2011 3 EI904
Electrical Hookup
240-volt source – from the model number and
nameplate determine KW size and amp draw.
According to local codes, building type, wiring
length, etc. use appropriate wiring conductor
size and source circuit breaker. Connect to the
terminal block.
Grounding – route and install appropriate size
ground conductor between the ground lug and
the building service panel ground bus. This
must be a conductor size according to the total
amp rating of the appropriate unit. Conduit is
not an adequate ground conductor.
Operation – this unit “turns on” or heats when
24 volts are applied to the yellow and black
wires. Via an external 24-volt transformer or
an external transformer applying 24 volts
through a contact (airflow switch, danger end
switch, etc.) arrange your control circuit to
apply 24VAC power when you want boost heat.
SUMMER OR COOLING DISABLE
This module must be disabled during the cooling cycle to prevent adding heat to the air conditioning
operation.
Select one of the following 3 installation techniques or methods:
A. Extend HP reversing valve wire to the designated “RV” tab. If the heat pump logic is “logic
high” for heating, cut the W1/W2 resistor on the control board with a side cutter. The location of
this resistor is shown below. Review your heat pump’s installation manual to make certain of
your heat pump’s reversing valve logic.
B. Add a manual (summer) disable toggle switch between “R” and “RV” tab.
C. Simply turn off 24ØV breaker during the cooling season.
Method B or C should be used for boost heater applications.
The locaation of the W1/W2 resistor is circled above.