33
No. Error type
Explanation
Possible solution
20
Lockout
Error gas valve V1, flame ionisation signal detec-
ted longer than 5 seconds after burner stop.
Check closing position of valve V1 within gas combi
valve, replace gas valve.
21
Lockout
Error gas valve V2, flame ionisation signal detec-
ted longer than 5 seconds after burner stop.
Check closing position of valve V2 within gas combi
valve, replace gas valve.
22
Lockout
APS contact does not close during prepurge.
Check setting APS, check if fan is running.
23
Lockout
APS contact remains closed when fan is off.
Check setting APS
27
Lockout
APS contact opens during operation.
Check setting APS
30
Lockout
CRC error in control system parameters (P11-
P40).
Check parameter settings of P11-P40, change value of
one parameter within P11-P40 (lockout disappears),
change all parameters back to original settings.
31
Lockout
CRC error in boiler safety parameters (V1-V16). Check parameter settings of V1-V16, change value of
one parameter within V1-V16 (lockout disappears),
change all parameters back to original settings.
32
Interlock
Power supply voltage to boiler controller is too
low.
Check fuse of boiler controller, check power supply to
boiler controller.
40
Lockout
Water flow switch has been interrupted when
pump being enabled.
Check pump operation, check water flow through the
boiler, check functionality of water flow switch.
x.y.
Lockout
(all lockout codes which are not listed above)
Internal lockout of boiler controller.
Press reset. Change boiler controller when lockout can
not be reset or occurs more frequently.
Lockouts