Dunkirk Q90-200 Series II - Manual (Page 33)

33
SERVICE HINTS
POWER ON
STAND BY
THERMOSTAT
CALLS FOR HEAT
CIRCULATOR
ENERGIZES THRU
2K1 CONTACTS
IBC SELFCHECK OF
INTERNAL CIRCUITRY
1-2 SEC
IBC
CHECKS
N.O. AIR
PRESSURE
SWITCH
CONTACTS
FALSE
POSITIVE
PROOF OF
AIRFLOW. IBC WAITS
FOR 45 SEC
FOR AIR PRESSURE
SWITCH CONTACTS
TO OPEN
CLOSED CLOSED
DRAFT INDUCER
ENERGIZES THRU
1K1 CONTACTS
OPEN
IBC
WAITS FOR
UP TO 5 MINUTES
FOR AIR PRESSURE
SWITCH CONTACTS TO CLOSE
INDICATING FAN
SUCTION
PRESENT
CLOSED
CONTROL LOCKOUT. PURGE LIGHT
BLINKS. RESET REQUIRED. CIRCULATOR
REMAINS ENERGIZED AS LONG AS
THERMOSTAT CONTINURES TO CALL FOR
HEAT
OPEN
PURGE LIGHT IS ON. AIRFLOW PROVED.
DRAFT INDUCER RUNS FOR 15 SEC PREPURGE
OPEN
PURGE LIGHT GOES OUT. HOT SURFACE IGNITER
POWERED THRU 5K1 5K2 CONTACTS FOR 20
SEC IGNITER WARMUP. BRIGHT YELLOW
ORANGE GLOW OF THE HOT SURFACE IGNITER
CAN BE OBSERVED THRU THE OBSERVATION
PORT IN FRONT OF BOILER SECTION JUST
ABOVE IGNITER, IGNITOR LIGHT IS ON
GAS VALVE ENERGIZED THRU 3K1 AND 4K1.
CONTACTS, VALVE LIGHT IS ON.
GAS VALVE OPENS FOR 5 SEC TRIAL FOR
IGNITION. BLUE ORANGE GLOW OF THE BURNER
CAN BE SEEN THRU OBSERVATION PORT.
2 SEC INTO THE 5 SEC IGNITION TRIAL. POWER
IS TURNED OFF TO THE HOT SURFACE IGNITER.
IGNITER LIGHT IS OFF.
DURING THE LAST 2 SEC OF THE 5 SEC IGNITION
TRIAL MAIN BURNER FLAME IS PROVED BY FLAME
RECTIFICATION A FLAME SIGNAL TO IBC. GAS VALVE
REMAINS ENERGIZED. BOILER RUNS.
DOES
MAIN
BURNER PROVE
FLAME WITHIN INITIAL
TRIAL FOR
IGNITION
PERIOD?
CONTROL WILL ATTEMPT 2
ADDITTIONAL IGNITION SEQUENCES.
STARTING WITH PREPURGE.
IF MAIN BURNER DOES NOT PROVE
FLAME IN 3 TRIALS, CONTROL
LOCKOUT. VALVE/FLAME LIGHT BLINKS,
RESET IS REQUIRED. THIS PROBLEM IS A
RESULT OF NOT ESTABLISHING FLAME SIGNAL.
NORMAL
OPERATION
YES
NO
12 - DETAILED SEQUENCE OF OPERATION