BoilerFaultCodesTechnical description
Mounting fault sensor
What causes this fault?
This fault occurs when the boiler's control board detects that a temperature sensor has physically come loose from the internal pipework. The most common reason is a weakened or displaced metal retaining clip, meaning the sensor can no longer accurately monitor the water temperature to prevent overheating.
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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