Troubleshooting: Continuous Fan Sequence of Operation
CONTINUOUS LOW SPEED FAN SEQUENCE OF OPERATION
MANUAL FAN SELECTION MADE AT THERMOSTAT.
AFTER 2 SECOND DELAY, INDOOR BLOWER IS
ENERGIZED ON CONTINUOUS FAN SPEED.
YES |
| YES |
|
|
|
YES
THERMOSTAT CALLS FOR FIRST STAGE COOL.
YES
INDOOR BLOWER RAMPS TO FIRST STAGE
COOLING SPEED AFTER A 2−SECOND DELAY.
FIRST−STAGE COOL DEMAND SATISFIED?
NO 
SECOND STAGE COOL DEMAND
INDOOR BLOWER RAMPS TO SECOND
STAGE COOL SPEED
SECOND STAGE COOL DEMAND SATISFIED?
YES
INDOOR BLOWER RAMPS DOWN TO FIRST STAGE
COOL SPEED.
THERMOSTAT CALLS FOR FIRST−STAGE HEAT.
YES
AFTER 45−SECOND DELAY, INDOOR BLOWER
SWITCHES TO LOW HEAT SPEED.
FIRST−STAGE HEAT DEMAND SATISFIED.
NO 
THERMOSTAT CALLS FOR SECOND−STAGE HEAT.
YES 
INDOOR BLOWER SWITCHES TO HIGH HEAT SPEED
AFTER 30−SECOND RECOGNITION PERIOD.
YES
SECOND−STAGE HEAT DEMAND SATISFIED.
YES
INDOOR BLOWER RAMPS DOWN TO LOW
HEAT SPEED.
YES
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