BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's safety monitoring system detects that harmful exhaust gases are not being safely pushed out of the flue or that the air supply is restricted. The most common reasons are a malfunctioning fan that cannot clear the gases, a blocked venturi tube, or a sensor that is failing to confirm the boiler is breathing correctly.
This fault is more common during periods of high wind, which can cause pressure fluctuations in the flue that trigger the safety sensors.
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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