Lennox G61MP Series Unit Information

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HEATING SEQUENCE OF OPERATION
LOW FLAME SIGNAL
(Does not affect control operation)
DS1 SLOW FLASH, DS2 FAST FLASH.
FLAME SIGNAL ABOVE
(u0.22 microamps)
NO
YES
CONTINUED ON NEXT PAGE
YES
SINGLE−STAGE THERMOSTAT MODE
(E20 SET AT SINGLE")
TWO STAGE THERMOSTAT MODE
(E20 SET AT TWO")
YES
YES
START SECOND−STAGE RECOGNITION
ON DELAY (10 OR 15 MINUTES).
DS1 AND DS2 SIMULTANEOUS FAST FLASH.
45−SECOND INDOOR BLOWER ON DELAY BEGINS.
DS1 AND DS2 SIMULTANEOUS FAST FLASH.
YES
YES
PRIMARY, SECONDARY, ROLLOUT AND BACKUP
SECONDARY LIMIT SWITCHES CLOSED?
NO
GAS VALVE OFF, COMBUSTION AIR INDUCER OFF,
INDOOR BLOWER ON. DS1 SLOW FLASH, DS2 ON.
HAS PRIMARY, SECONDARY, ROLLOUT OR BACKUP
SECONDARY LIMIT SWITCH CLOSED WITHIN 3 MINUTES?
(Indoor blower on low speed during 3−minute period)
YES
FIRST−STAGE (LOW FIRE)
PRESSURE SWITCHES CLOSED?
LIMIT SWITCH WATCHGUARD MODE.
GAS VALVE OFF, COMBUSTION AIR INDUCER OFF,
INDOOR BLOWER OFF WITH DELAY.
DS1 AND DS2 ALTERNATING SLOW FLASH.
IS 60−MINUTE RESET PERIOD COMPLETE?
THERMOSTAT CALLS FOR HEAT.
DS1 AND DS2 SIMULTANEOUS FAST FLASH.
SEE BOX A.
NO
YES
GAS VALVE OFF. COMBUSTION AIR INDUCER ON.
INDOOR BLOWER OFF AFTER DELAY.
DS1 OFF, DS 2 SLOW FLASH.
NO
YES
C
FIRST−STAGE HEAT DEMAND SATISFIED?
DS1 AND DS2 SIMULTANEOUS SLOW FLASH.
GAS VALVE OFF, COMBUSTION AIR INDUCER
OFF FOLLOWING POST PURGE.
INDOOR BLOWER OFF WITH DELAY
DS1 AND DS2 SIMULTANEOUS SLOW FLASH
YES
SECOND−STAGE HEAT DEMAND.
SECOND−STAGE HEAT DEMAND REQUIRED?
DS1 AND DS2 SIMUTANEOUS SLOW FLASH.
NO
SECOND STAGE PRESSURE SWITCHES CLOSED?
ABNORMAL FLASH CODE.
NOTE − IF SECOND−STAGE PRESSURE SWITCHES
WERE ORIGINALLY FOUND CLOSED,
ABNORMAL CODE WILL FLASH.
SECOND−STAGE PRESSURE SWITCHES CLOSED
AT BEGINNING OF HEAT DEMAND?
DS1 OFF, DS2 SLOW FLASH.
YES
NO
SECOND−STAGE 30−SECOND DELAY ON BEGINS.
DS1 AND DS2 SIMULTANEOUS FAST FLASH
SECOND−STRAGE COMBUSTION AIR INDUCER
ON. SECOND−STAGE GAS VALVE ON. HIGH
HEAT INDOOR BLOWER SPEED ON.
DS1 AND DS2 SIMULTANEOUS FAST FLASH.
YES
SECOND−STAGE PRESSURE SWITCHES CLOSED
IN LESS THAN TEN (10) SECONDS?
DS1 AND DS2 SIMULTANEOUS FAST FLASH.
YES
NO
RETURNS TO FIRST−STAGE HEAT MODE WHICH
CONTINUES UNTIL SECOND−STAGE PRESSURE
SWITCHES CAN BE PROVEN or HEAT DEMAND IS
SATISFIED. FIVE (5) MINUTE WAIT PERIOD
INITIATED BEFORE RETRY. WERE 5 ATTEMPTS
MADE FOR SECOND−STAGE HEAT?
YES
NORMAL OPERATION.
DS1 AND DS2 SIMULTANEOUS SLOW FLASH.
SECOND STAGE HEAT DEMAND
DS1 AND DS2 SIMULTANEOUS SLOW FLASH.
NO
YES
NO
YES
CONTINUED

Lennox G61MP Series Specifications

General

Brand	Lennox
Model	G61MP Series
Category	Furnace
Language	English