BoilerFaultCodesYour boiler has shut down because 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: High flue temperature fault
What causes this fault?
This fault occurs when the internal heat exchanger isn't transferring heat efficiently to the water, causing the leftover heat to escape into the exhaust flue at dangerous levels. The most common reasons are a buildup of debris and sludge inside the main heat exchanger or a failing sensor that is incorrectly reading the exhaust temperature.
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 0A7 — 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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