BoilerFaultCodesYour boiler has detected a short circuit in the sensor that monitors your hot water temperature, meaning it can no longer accurately heat your tap water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Constant temperature control units
What causes this fault?
This fault occurs when the electrical signal from the hot water sensor becomes constant, usually because the internal wiring of the sensor has failed or become damaged. This prevents the boiler from knowing the temperature of the water in your cylinder, causing it to stop heating your taps to prevent overheating. The most common reason is a component failure within the probe itself or water ingress affecting the electrical connections.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 50:1 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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