York International DFAA User's Information, Maintenance And Service Manual page 24

107273-UUM-C-0306
NO IGNITION ARC ESTABLISHED
1. RESET CONTROL: - MOTOR STARTS - COMPLETES 30 SECOND PREPURGE CYCLE, 8 SECOND SAFE START CHECK SERIES
IN ORDER FOR THE FOLLOWING FUNCTIONAL TEST TO BE MADE, THE CONTROL MUST BE RESET AND THE TESTS
MONITORED DURING THE 4 SECOND HONEYWELL SERIES TRIAL FOR IGNITION THAT OCCURS AT THE END OF THE
30 SECOND PREPURGE CYCLE, AND THE 8 SECOND SAFE START CHECK.
2. CHECK FOR 120 VAC BETWEEN TWO LEADS OF TRANSFORMER
3. CHECK ELECTRICAL WIRING AND CONNECTIONS
4. CHECK HIGH VOLTAGE LEAD AND CONNECTION
TO IGNITION ELECTRODE ROD
.
5. INSPECT IGNITION ELECTRODE FOR
CRACKED INSULATOR AND CORRECT GAP
6. REPLACE PRIMARY IGNITION CONTROL
NO IGNITION - NO GAS VALVE
1. RESET CONTROL - MOTOR STARTS - AFTER 30 SECOND PREPURGE CYCLE AND 8 SECOND SAFE START CHECK
MOTOR CONTINUES TO RUN BUT FLAME IS NOT ESTABLISHED
IN ORDER FOR THE FOLLOWING FUNCTIONAL TEST TO BE MADE, THE CONTROL MUST BE RESET AND THE TESTS
MONITORED DURING THE 4 SECOND HONEYWELL SERIES TRIAL FOR IGNITION THAT OCCURS AT THE END OF THE
30 SECOND PREPURGE CYCLE, AND THE 8 SECOND SAFE START CHECK
2. CHECK FOR 24 VAC AT THE 24 V PRIMARY CONTROL INPUT
TERMINALS LABELED YELLOW AND BROWN
3. CHECK AIR PROVING SWITCH FOR:
A. ANY IMPAIRMENT THAT WOULD KEEP IT FROM CLOSING OR OPENING
B. ELECTRICAL CONTINUITY; SWITCH IS NORMALLY OPEN
C. REPLACE SWITCH AS NECESSARY
4. CHECK (WHEN APPLICABLE) EXTERNAL 60 SECOND PREPURGE
TIMER (JUMPER AROUND TIMER FROM AIR SWITCH). SHOULD
PRIMARY IGNITION CONTROL BECOME ENERGIZED.
REPLACE TIMER
24
- GAS VALVE OPENS, REGULATING ADEQUATE GAS PRESSURE.
- NO FLAME ESTABLISHED - PRIMARY CONTROL LOCKS OUT AFTER 4 SECOND HONEYWELL SERIES
TRIAL FOR IGNITION PERIODS
OK
OK
OK
OK
OK
OK
CHECK ELECTRICAL WIRING AND
OK
CONNECTIONS PER WIRING DIAGRAM
CHECK THE FLAME SENSING CIRCUIT FOR:
1. GROUNDED FLAMEROD
2. DAMAGE TO FLAMEROD LEAD
INSULATION
NOTE: MAKE SURE THE FLAMEROD CIRCUIT
AND/OR PRIMARY CONTROL IS MOISTURE
FREE
REPLACE PRIMARY IGNITION CONTROL
OK
REPLACE PRIMARY IGNITION CONTROL
OK
OK
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