BoilerFaultCodesTechnical 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.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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