Honeywell S8701 - Manual (Page 6)

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S8701/S8702 DIRECT SPARK IGNITION CONTROLS
Fig. 4. S8701/S8702 Sequence of Operation for 1 Trial Models (B, D, J, and K Models).
START
PREPURGE
(J AND K MODELS ONLY)
SAFE START CHECK
TRIAL FOR IGNITION
MAIN BURNER
OPERATION
END
THERMOSTAT CALLS FOR HEAT
SAFE START CHECK. LED BLINKS RAPIDLY.
PREPURGE - J & K MODELS ONLY
SPARK GENERATOR POWERED
MAIN VALVE OPERATORS OPEN.
IF NO SPARK, B, D, J, AND K MODELS GO INTO LOCKOUT
AFTER ONE (1) TRIAL FOR IGNITION PERIOD.
ALARM CIRCUIT IS ACTIVATED.
LED IS ON STEADY. SYSTEM MUST BE RESET.
IF FLAME CURRENT SENSED:
(MUST BE SENSED AT BOTH
BURNERS ON S8702)
SPARK GENERATOR IS SHUT OFF.
LOCKOUT TIMER IS RESET.
IF FLAME CURRENT IS NOT SENSED:
B, D, J, AND K MODELS GO INTO LOCKOUT
AFTER ONE (1)TRIAL FOR IGNITION PERIOD.
LED IN ON. SYSTEM MUST BE RESET.
MAIN BURNER OPERATION
UNIT MONITORS BURNER
FLAME CURRENT.
LOSS OF FLAME
SPARK GENERATOR IS POWERED.
B, D, J, AND K MODELS GO INTO LOCKOUT AFTER
ONE (1) TRIAL FOR IGNITION PERIOD. LED IS ON STEADY.
SYSTEM MUST BE RESET.
TEMPERATURE CONTROLLER
IS SATISFIED.
POWER TO UNIT IS INTERRUPTED.
VALVES CLOSE.
MAIN BURNER(S) ARE OFF.
DURING NORMAL OPERATION LED BLINKS ONCE PER SECOND.
M18058
NOTES: B, D, J, AND K MODELS GO THROUGH ONE (1) TRIAL FOR IGNITION PERIOD BEFORE LOCKOUT.
LOCKOUT = VALVE CLOSED PLUS SPARK OFF PLUS ALARM ACTIVATED PLUS LED ON STEADY.