If the appliance has just been fitted with a new PCB the appliance will perform an initial test check of the flue thermistor, this is only performed once when the boiler is new or a new PCB is fitted.
This can be considered as correct operation and once this check is completed normal operation should resume.
During this initial test check of the flue thermistor the appliance will automatically fire without a demand and stop the pump running during this time, this is to ensure the fitment and operation of the flue gas thermistor - the appliance checks the flue thermistor heats correctly, if it does not heat enough an A3 error code will be displayed.
If the appliance cannot fire due to a further fault it will continue to try to perfom this self check when it can fire, this initial self check cannot be skipped.
This information should be considered before continuing.
If A3 fault code is displayed click here.
This can be considered as correct operation and once this check is completed normal operation should resume.
During this initial test check of the flue thermistor the appliance will automatically fire without a demand and stop the pump running during this time, this is to ensure the fitment and operation of the flue gas thermistor - the appliance checks the flue thermistor heats correctly, if it does not heat enough an A3 error code will be displayed.
If the appliance cannot fire due to a further fault it will continue to try to perfom this self check when it can fire, this initial self check cannot be skipped.
This information should be considered before continuing.
If A3 fault code is displayed click here.
