BoilerFaultCodesYour boiler has sensed that the internal temperature inside the casing is getting too hot and has 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: Case temperature: Temperature within boiler casing too high
What causes this fault?
This fault occurs when the air inside the boiler's outer box reaches a dangerously high temperature, often because heat is escaping from the main combustion area. The most common reasons are a crack in the main heat exchanger or a failing seal that is letting hot gases leak into the casing instead of going out through the flue.
This fault is more common during the winter months when the boiler is working harder and running for longer periods, causing heat to build up more rapidly.
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 3 — no call-out fees, no surprises.
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