BoilerFaultCodesYour boiler has stopped working because a sensor that measures the temperature of the water leaving the unit has failed or disconnected.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Heating flow thermistor fault
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read the temperature of the water being sent to your radiators. The most common reason is that the sensor has either suffered an internal electrical failure or the wiring connecting it to the main control board has become loose or corroded. To prevent the unit from overheating, the boiler shuts down as a safety precaution until the sensor is replaced.
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 F2 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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