BoilerFaultCodesYour boiler has shut down because it detected that the water inside has become too hot, causing a safety switch to trigger.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check continuity of water pressure switch and overheat 'stat. Check temperatures; if below 90°C replace stat, if above 90°C check CH/HW thermistors.
What causes this fault?
This fault occurs when the water within the heat exchanger reaches a dangerously high temperature, triggering a safety sensor to cut off the gas for your protection. The most common reasons for this are a lack of water circulation caused by a failing pump, a blockage in the pipework, or a sensor that has become faulty and is giving a false reading.
This issue often surfaces when you first turn your heating back on in autumn, as internal pumps can seize up after being idle during the summer months.
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 Overheat 'stat tripped — no call-out fees, no surprises.
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Ideal Response 80 100 120 is discontinued — time for a new one?
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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