BoilerFaultCodesYour hot water system is getting too hot and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: D.H/W sensor overheating error
What causes this fault?
This fault occurs when the internal temperature sensor detects that your hot water is becoming dangerously hot, triggering an emergency shutdown to prevent scalding. The most common reason is a buildup of limescale or debris inside the heat exchanger which restricts water flow, but it can also be caused by a mechanical failure in the diverter valve or a faulty sensor giving a false reading.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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