BoilerFaultCodesYour boiler has detected a problem with the internal sensor that measures the temperature of the water used to heat your radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: CH flow sensor fault. CH flow sensor 10000 - 12000 ohms at room temperature. Wiring and connections to sensor.
What causes this fault?
This fault occurs when the boiler's internal control board loses communication with the sensor that monitors the temperature of the water leaving the unit. The most common cause is the sensor itself failing due to age or internal wear, though it can also be triggered by loose or damaged wiring connections inside the casing.
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 F0 — 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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