BoilerFaultCodesYour boiler has reached an unsafe temperature because water isn't circulating properly through the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow/return valves closed; Stuck pump. Appears if the boiler has overheated.
What causes this fault?
This fault occurs when water cannot travel through the boiler’s internal pipework fast enough to carry away the heat, leading to a build-up of extreme temperature. The most common reasons are a pump that has seized up or internal blockages that are preventing the water from flowing freely through the system.
This issue is frequently seen at the start of autumn when heating systems are switched back on after being idle all summer, which can cause the pump to stick.
DIY fix possible
Wait for the boiler to cool down for at least 20 minutes.Ensure all radiator valves and any internal isolation valves are fully open.Press the Reset button on the control panel to clear the fault.
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A boiler cover plan would cover faults like 02 — no call-out fees, no surprises.
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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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