BoilerFaultCodesYour boiler has lost its ability to monitor the temperature of the stored hot water, meaning you may have lukewarm water or no hot water at all.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Domestic hot water storage cylinder thermistor fault
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of the water inside the storage cylinder fails or provides an illogical reading. The most common reason is that the internal components of the sensor have degraded over time, or the electrical connection between the sensor and the main control board has become loose or damaged.
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 F7 — no call-out fees, no surprises.
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