BoilerFaultCodesTechnical description
Flue thermostat / flue pressure switch tripped
What causes this fault?
This fault occurs when the boiler's safety sensors detect that harmful exhaust fumes are not being effectively cleared through the flue pipe to the outside. The most common reasons are a buildup of debris in the internal air tubes, a failing fan that cannot push the gases out, or a physical blockage in the flue itself.
This fault can be more common during periods of high winds, which can create back-pressure in the flue and cause the pressure switch to trip.
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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