Advertisement
WIRING OPTIONS 1 AND 2: In most Furnace/Thermostat systems, if a circuit is made between R and G on the
furnace, in an attempt to make the furnace blower operate, the Y contacts are also energized, because the thermostat
has an internal connection between its G and Y terminals. This will cause the air conditioning unit to operate as well.
The Furnace Interlock in the SFM takes the thermostat's G terminal out of the circuit whenever there is a call for the
Energy Recovery Ventilator to operate.
WIRING OPTIONS 3 AND 4: The SFM requires 24 VAC power to operate. This is usually provided by the furnace
control. If there is no Furnace connection, it is possible to power the SFM with an external transformer; in this
case, make no connections to any appliance other than the TR90, TR130, TR200, TR300. Use Option 3 or 4 when
connecting a larger commercial Energy Recovery Ventilator unit.
All specifications are subject to change without notice unless approved in submittal by S&P USA.
SFM-Submittal_v1_012022
Advertisement
