BoilerFaultCodesTechnical description
Water differential pressure switch (insufficient water or circulation)
What causes this fault?
This fault occurs when the boiler's control system fails to detect a steady flame after several attempts to light. The most common reasons are a buildup of carbon on the ignition parts, an inconsistent fuel supply, or a sensor that has become too dirty to 'see' the flame. It functions as a safety shutdown to ensure gas does not flow without being safely burned.
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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