BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue thermistor fault
What causes this fault?
This fault occurs when the boiler's internal computer stops receiving a reliable signal from the sensor that monitors exhaust gas temperatures. It usually happens because the sensor has failed due to heat fatigue or a loose electrical connection has developed in the wiring. As a safety measure, the boiler shuts down to prevent the system from operating without knowing if the exhaust gases are at a safe temperature.
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 E2 — no call-out fees, no surprises.
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