BoilerFaultCodesTechnical description
Water pressure switch or flue thermostat failure
What causes this fault?
This fault occurs when the boiler’s safety controls detect that either the internal water pressure has dropped too low or the exhaust gases have become too hot. It is often triggered by a leak in the system reducing pressure, or a build-up of debris causing the heat exchanger to overheat. In some cases, the sensors themselves may have physically failed or lost their connection to the main control board.
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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