BoilerFaultCodesYour boiler has shut down because the exhaust gases have reached a dangerously high temperature, triggering a safety sensor 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 overheat lockout
What causes this fault?
This fault occurs when the internal temperature of the boiler rises significantly above safe operating limits, causing the safety sensor to trip. The most common reason is a buildup of limescale or debris inside the main heat exchanger, which prevents heat from being transferred to the water and forces it out through the exhaust instead.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like E131 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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