BoilerFaultCodesYour boiler has overheated, prompting a safety switch to shut the system down 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: Safety thermostat or flue thermostat tripped
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety sensor to cut the power. The most common reasons are a failed pump stopping water from moving or a blockage in the heat exchanger caused by a buildup of sludge and debris.
This issue often appears when the heating is first turned on after summer, as the internal pump can seize up after months of inactivity.
DIY fix possible
Check that all radiator valves are fully openEnsure the system pressure is between 1.0 and 1.5 barAllow the boiler to cool down and then press the 'Reset' button
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 E110 — no call-out fees, no surprises.
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Potterton Gold Combi HE 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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