BoilerFaultCodesTechnical description
Boiler sensor (flow) fault
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not rotating at the speed required to safely clear combustion gases from the flue. The most common reasons are a build-up of debris within the fan motor, a blockage in the air pressure tubes, or electrical wear and tear on the internal circuit board which prevents it from controlling the fan properly.
This fault is slightly more common in autumn and winter, as heavy winds can create back-pressure in the flue, or spiders may crawl into the pressure sensing tubes during colder months.
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.
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