BoilerFaultCodesYour boiler has sensed that the exhaust fumes are getting too hot and has shut down as a safety precaution to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue gases over temperature probe
What causes this fault?
This fault occurs when the internal temperature of the exhaust gases exceeds safe limits, potentially causing damage to the boiler's internal plastics. The most common reasons are a build-up of debris or limescale inside the heat exchanger, which prevents heat from transferring to the water, or a failure of the internal insulation panels meant to contain the burner's heat.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E090 — 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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