BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors exhaust gases, and it has locked the system down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Permanent fault. Flue temperature sensor short-circuited, sensor not or badly connected, bad connection or sensor fault.
What causes this fault?
This fault occurs when the boiler's internal safety system detects an irregular electrical signal from the sensor monitoring the heat of the exhaust gases. The most common reason is that the sensor has developed a physical defect or the wiring connecting it to the main control board has come loose or been damaged. Because the boiler can no longer accurately monitor flue temperatures, it shuts down to prevent any risk of overheating.
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 E.04 – .04 — 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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