BoilerFaultCodesYour boiler has become too hot and has shut itself down as a safety precaution 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: Overheated – try bleeding your radiators
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 lack of water flow caused by a failing pump, a blockage in the system, or air trapped within the pipework. Essentially, the heat cannot be moved away from the boiler quickly enough, causing it to overheat.
This fault is often seen in autumn when heating systems are turned on for the first time after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check that your boiler pressure is between 1.0 and 1.5 barEnsure all radiator valves and the boiler isolation valves are fully openBleed your radiators to remove trapped air that might be blocking water flow
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 E1 — no call-out fees, no surprises.
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Baxi Avanta 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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