BoilerFaultCodesTechnical description
Code plug missing or failed. CH or DHW Sensor fault or out of position. Air pressure switch fault or condense in tubes. Fan fail or stiff. Blocked flue. Faulty harness. Board fault.
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with its key safety components or senses that air isn't moving through the system correctly. It often signifies that the fan cannot spin properly or the sensors responsible for monitoring heat and airflow have detected an unsafe operating condition. These sensors act as a safety net, shutting the system down to prevent damage or the release of exhaust gases into the home.
This issue is more frequent during periods of heavy rain or high humidity, as moisture can build up within the air pressure tubes and disrupt the signal required for the boiler to fire.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.