BoilerFaultCodesYour boiler has detected a problem with a temperature sensor that controls the heat of your water, which might cause your heating or hot water to stop working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Mixer temperature sensor faulty: Mixer temperature sensor (MF) connected to IPM faulty.
What causes this fault?
This fault occurs when the internal control system loses communication with the sensor responsible for monitoring water temperature at the mixing valve. It is usually caused by the sensor failing due to age or a loose electrical connection between the sensor and the boiler's main control module. When this happens, the boiler shuts down as a safety precaution because it can no longer accurately regulate the heat of the water.
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 Fault 30 / 7 — 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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