Cooling Sequence Of Operation; Continuous Low Speed Fan Sequence Of Operation - Lennox G60UHV Service Manual

IS POLARITY REVERSED?
SIGNAL IMPROPER
GROUND AT DS.
NO
SIGNAL HOLDS
PROPER GROUND?
UNTIL UNIT IS
PROPERLY
GROUNDED.
THERMOSTAT CALLS FOR FIRST−STAGE COOL.
COMPRESSOR AND CONDENSER FAN
INDOOR BLOWER ENERGIZED ON FIRST STAGE
COOL SPEED AFTER 2 SECOND DELAY.
FIRST−STAGE DEMAND FOR COOL SATISFIED?
THERMOSTAT CALLS FOR SECOND−STAGE COOL.
INDOOR BLOWER RAMPS UP TO SECOND−STAGE COOL SPEED.
SECOND−STAGE DEMAND FOR COOL SATISFIED?
UNIT RETURNS TO FIRST STAGE COOL

CONTINUOUS LOW SPEED FAN SEQUENCE OF OPERATION

THERMOSTAT CALLS FOR FIRST STAGE COOL.
INDOOR BLOWER RAMPS TO FIRST STAGE
COOLING SPEED AFTER A 2−SECOND DELAY.
FIRST−STAGE COOL DEMAND SATISFIED?
YES
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.

COOLING SEQUENCE OF OPERATION

POWER ON
NO
YES
IS THERE IS VOLTAGE
ABOVE 75 VOLTS?
ENERGIZED.
NO
YES
MANUAL FAN SELECTION MADE AT THERMOSTAT.
AFTER 2 SECOND DELAY, INDOOR BLOWER IS
ENERGIZED ON CONTINUOUS FAN SPEED.
YES
YES
YES
SIGNAL POLARITY REVERSED.
DS1 FAST FLASH, DS2 SLOW FLASH.
NO
LOW VOLTAGE SIGNAL AT DS HOLDS
UNTIL VOLTAGE RISES ABOVE 75 VOLTS.
YES
YES
COMPRESSOR AND CONDENSER FAN DE−ENERGIZED.
INDOOR BLOWER DE−ENEGIZED.
YES
THERMOSTAT CALLS FOR FIRST−STAGE HEAT (W).
AFTER 45−SECOND DELAY, INDOOR BLOWER
SWITCHES TO LOW HEAT SPEED.
FIRST−STAGE HEAT DEMAND SATISFIED.
THERMOSTAT CALLS FOR SECOND−STAGE HEAT (W).
INDOOR BLOWER SWITCHES TO HIGH HEAT SPEED
AFTER 30−SECOND RECOGNITION PERIOD.
SECOND−STAGE HEAT DEMAND SATISFIED.
INDOOR BLOWER RAMPS DOWN TO LOW
HEAT SPEED.
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YES
NO
YES
YES
YES
YES