Ariston Euro Combi A/27 MFFI Servicing Instructions page 22

B
DOES THE FAN
COME ON?
YES
C
22
NO
BOILER
SHUTDOWN?
NO
PUMP
SAFETY DEVICE
ACTIVATED?
NO
INTERNAL
SAFETY DEVICE
FOR PCB
ACTIVATED?
NO
IS THERE POWER
TO THE FAN?
YES
1) Replace fan
YES 1) Reset the boiler
1) Check/replace differential
pressure switch for pump
2) Check/replace wiring
3) Check/replace PCB wire
YES
4) Check/replace power
supply PCB
5) Check/replace control
PCB
1) Check/replace air
pressure switch/wiring
2) Check whether reset
YES
button is stuck
3) Check/replace flame
detection electrode
1) Check/replace wiring
Check/replace PCB wire
2)
3) Check/replace power
NO
supply PCB
4) Check/replace control
PCB
5) Check/replace air
pressure switch
B029