Bryant 582A manual Controls, Operating Sequence

CONTROLS

OPERATING SEQUENCE

Heating — When the thermostat calls for heating, terminal “W” is energized, starting the induced-draft motor. When the hall- effect sensor on the induced-draft motor senses that it has reached the required speed, the burner ignition sequence be- gins. The indoor (evaporator) fan motor (IFM) is energized 45 seconds after flame is established. When the thermostat is satisfied and “W” is deenergized, the IFM stops after a 45-second time-off delay.

Cooling — When the system thermostat calls for cooling, 24 V

is supplied to the “Y” and “G” terminals of the thermostat. This completes the circuit to the contactor coil (C) and indoor (evapo- rator) fan relay (IFR). The normally open contacts of energized C close and complete the circuit through compressor motor (COMP) to outdoor (condenser) fan motor (OFM). Both motors start instantly. The set of normally open contacts of energized IFR close and complete the circuit through IFM. The IFM starts instantly.

On the loss of the thermostat call for cooling, 24 V is removed from both the “Y” and “G” terminals (provided the fan switch is in the “AUTO” position) deenergizing the compressor contactor and opening the contacts supplying power to compressor/OFM. After a 30-second delay, the IFM shuts off. If the thermostat fan selector switch is in the “ON” position, the IFM will run continuously.

NOTE: On units with a Time Guard® II device: Once the com- pressor has started and then stopped, it cannot be re-started again until five minutes have elapsed.

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