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30
7.10.2 FAULT FINDING TEST ‘A’
YES
NO
NO
MAINS
ON E.V.G.
NO
YES
NO
NO
YES
YES
YES
NO
IS
THERE 24 Vdc
BETWEEN TERMINALS
CN8.4 & CN8.5
ON PCB
A
REPLACE
SENSING/SPARK
ELECTRODE AND
LEAD
REPLACE PCB
SENSING
SPARK ELECTRODE
AND LEAD
OK
CHEK
SENSING/SPARK
ELECTRODE AND
LEAD
END
LOCKOUT
IGNITION
REPLACE EVG
CHECK GAS
EVG OK
IGNITION
SPARK AT
ELECTRODE
CHECK WIRING AND
CONNECTIONS OR
HIGH LIMIT THERMOSTAT
CHECK
SENSING/SPARK
ELECTRODE AND
LEAD
IS
THERE 230 Vac
BETWEEN TERMINALS
CN5.1 & CN5.2
ON PCB
IS
THERE 0 Vdc
BETWEEN TERMINALS
CN8.7 & CN8.8
ON PCB
NO
YES
NO
CHECK WIRING
AND
CONNECTIONS
NO
DO THE
AIR FLOW SWTCH
TURN ON
CHECK WIRING AND
CONNECTIONS, AIR FLOW
SWITCH AND CONTROL
BOARD
YES
NO
ARE THE
VENTURI TUBE
AND THE SILICONE
AIR TUBES
CLEAN
CHECK/CLEAN THE
VENTURI TUBE AND
SILICONE AIR
TUBES
IS
THE AIR DP >
11 mmCH2O
CHECK THE FAN
AND/OR FLUE GAS
TUBE
CHECK REPLACE
AIR FLOW SWITCH
NO
YES
YES
REPLACE THE
CONTROL BOARD
YES
NO
NO
IS
THERE 230 Vac
BETWEEN TERMINALS
CN6.1 & CN6.2
ON PCB
CHECK AND/OR
REPLACE PCB
IS
THERE 24 Vdc
BETWEEN TERMINALS
CN8.4 & CN8.8
ON PCB
CHECK AND/OR
REPLACE PCB
IS
THERE 24 Vdc
BETWEEN TERMINALS
CN8.4 & CN8.7
ON PCB
NO
CHECK WIRING AND
CONNECTIONS OR
HIGH LIMIT
THERMOSTAT
NO
YES
YES
YES
AFTER