BoilerFaultCodesYour boiler is failing to light the flame, which means you will not have any heating or hot water until it is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Delta T error – boiler failing to ignite. Could be due to a gas line valve being closed or a flue error.
What causes this fault?
This fault occurs when the boiler tries to start but cannot successfully light a stable flame. The most common reason is a disruption in the gas supply, such as a closed internal valve or an issue with the ignition components failing to create a spark.
This fault can sometimes occur during very windy weather, as high gusts can occasionally interfere with the air pressure required for the boiler to ignite safely.
DIY fix possible
Check that your gas emergency control valve and any internal gas lever valves are fully openInspect the flue terminal outside to ensure it is not blocked by leaves or debrisPress and hold the 'Reset' button for 3 seconds to attempt a restart
Find a Gas Safe engineer
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A boiler cover plan would cover faults like rE72 — 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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