Bryant 582A - Manual (Page 22)

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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