BoilerFaultCodesYour boiler has lost its ability to accurately measure the temperature of the water being heated for your radiators, causing it to stop running 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: If a fault occurs with the boiler thermostat the fault display screen will show "C/H Sensor Fault".
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring your central heating temperature fails to send a reliable signal to the main control board. The most common reason is that the sensor's internal electrical resistance has drifted out of range or the component has suffered a complete electrical failure due to age. In some cases, loose or damaged wiring between the sensor and the controller can also trigger this shutdown.
This fault is more common during the autumn months when the boiler is first switched on after a long summer break, as electrical components can seize or fail after being dormant.
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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A boiler cover plan would cover faults like C/H Sensor Fault — no call-out fees, no surprises.
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