Sterling ERMS - Manual (Page 10)

SEQUENCE OF OPERATION
STANDARD OPERATION
When the indoor fan motor of the HVAC equipment is energized, the 24vac control
relay in the ERV will be energized. The contactors for the supply fan, exhaust fan and
energy wheel will be activated and the ERV will begin operation. When the HVAC unit
indoor fan motor is de-energized, the 24vac control relay in the ERV will be de-
energized. The contactors for the supply fan, exhaust fan and energy wheel will be de-
activated and the ERV will stop operation.
MOTORIZED INTAKE DAMPER AND/OR EXHAUST DAMPER OPTION
Systems with a motorized intake or exhaust damper will open the damper fully when the
control circuit is activated prior to starting the energy wheel and blower motors.
ON/OFF FROST CONTROL OPTION
When the temperature falls below the frost threshold set point, a thermostat, located in
the outside air intake, will stop the operation of the ERV. When the temperature rises
above the frost threshold, the ERV will be re-activated.
PRE-HEAT FROST CONTROL OPTION
When the temperature falls below the frost threshold set point, a thermostat, located in
the outside air intake, will activate the pre-heat at the outside air intake to prevent frosting
on the energy wheel. When the temperature rises above the frost threshold, the thermostat
will de-activate the pre-heat.
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