BoilerFaultCodesYour boiler has shut down because it detected that the exhaust gases have become too hot, which is a safety feature to prevent damage to the internal components.
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 error
What causes this fault?
This fault occurs when the internal temperature sensors detect that the exhaust gases leaving your boiler have reached a dangerously high level. The most common reasons are a significant buildup of debris or limescale inside the heat exchanger, or damaged internal insulation panels that are no longer protecting the components from the burner's intense heat.
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.
Gas Safe Register →Protect yourself from future repair bills
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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