BoilerFaultCodesYour boiler has detected a fault with a temperature sensor and has shut down as a safety precaution, meaning you currently have no heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The heating flow thermistor is short circuited.
What causes this fault?
This fault occurs when the sensor responsible for monitoring the temperature of the water leaving your boiler fails or develops an electrical short. The most common reason is that the sensor has reached the end of its life due to constant heat cycles, or moisture has compromised the electrical connection. Because the boiler can no longer accurately measure the water temperature, it shuts down to prevent the system from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 31 — no call-out fees, no surprises.
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