BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing it 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 internal sensor responsible for monitoring the temperature of exhaust gases produces an incorrect reading or fails entirely. The most common reason is that the sensor has degraded over time or developed a short circuit, leading the boiler to shut down to prevent the unit from overheating or exhausting dangerous fumes.
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 E28 — 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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