BoilerFaultCodesYour boiler has sensed a blockage or a pump failure that is stopping water from moving through the system properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: High pressure – circulating pump failure orcircuit air locked
What causes this fault?
This fault occurs when water is unable to flow freely through the boiler, leading to a sudden rise in internal pressure. The most common reason is a failed circulating pump that can no longer push water around your radiators, or a large pocket of air trapped within the pipework that is acting as a physical blockage.
This issue is frequently seen in autumn when heating systems are turned back on after being idle all summer, which can cause the internal pump to seize.
DIY fix possible
Check that your radiator valves are openBleed your radiators to remove trapped airEnsure the system pressure gauge is within the correct range (usually 1.0 to 1.5 bar)
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like EE1 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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