Troubleshooting Flowcharts; Ignition Control Checkout Gc1 - Lennox G21Q3-40 Unit Information

VII − TROUBLESHOOTING FLOWCHARTS
TURN OFF UNIT POWER AT DISCONNECT
DOES THE CONTROL HALT OPERATION AND
LED LIGHTS IMMEDIATELY AFTER THE TRIAL
FOR IGNITION (WAIT 2 MINUTES TO MAKE SURE

IGNITION CONTROL CHECKOUT GC1

IS RED DIAGNOSTIC
LED LIT?
YES
FOR AT LEAST 3 SECONDS, THEN TURN
POWER BACK ON. ALLOW 3 SECONDS
FOR CONTROL TO POWER−UP.
IS RED DIAGNOSTIC
LED LIT?
LIT NOT LIT
UNIT WAS
IN LOCKOUT
REPLACE
GC 1 CONTROL
APPLY THERMOSTAT DEMAND
AND ALLOW UNIT TO IGNITE
AND ESTABLISH FLAME.
UNIT IS OUT OF POST
NO YES
CONTROL SHOULD OPERATE
PROPERLY PROCEED TO
ELECTRICAL CHECKOUT.
START HERE
CONTROL SHOULD OPERATE
PROPERLY PROCEED TO UNIT
WILL NOT RUN"−GAS CHECKS
AND SPARK CHECKS TO RULE
OUT OTHER POSSIBILITIES.
PURGE
REPLACE GC 1
CONTROL
Page 57
NO