Your boiler has detected that it is overheating because water is not 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: Dry fire
What causes this fault?
This fault occurs when the boiler's internal sensors detect a rapid, unsafe rise in temperature because water isn't flowing away from the heat exchanger quickly enough. The most common reasons are a failed internal pump that has stopped spinning or a physical blockage caused by a buildup of sludge and debris in the system pipework.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being dormant all summer, causing stuck pump components to fail.
DIY fix possible
Check that your boiler pressure is between 1 and 1.5 bar on the gaugeEnsure all radiator valves and any isolation valves under the boiler are fully openGently bleed your radiators to remove trapped airReset the boiler to see if the fault clears
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 E270 — no call-out fees, no surprises.
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Baxi GA Range 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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