BoilerFaultCodesYour boiler has shut itself down as a safety precaution because it has detected an internal fault that could lead to overheating or poor performance.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's control system detects that the internal temperature has exceeded safe limits or that water is not moving through the heat exchanger correctly. The most common reason is a failure in the communication between the temperature sensors or a pump that has seized and stopped circulating water. To prevent damage to the internal components, the boiler enters a protective shutdown mode.
This issue is more frequent during the first cold spell of autumn when pumps that have been idle all summer often struggle to restart or seize up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E28 — 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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