BoilerFaultCodesTechnical description
Gas supply is interrupted; boiler switches over to safety mode.
What causes this fault?
This fault occurs when the boiler tries to light the flame but fails to detect one, causing the system to shut down for safety. The most common reasons are a temporary interruption in your gas supply, worn-out ignition parts that can no longer create a spark, or a faulty internal valve that isn't opening properly.
This issue is more frequent during extreme cold spells, as external gas meters or regulators can occasionally freeze or become sluggish, restricting fuel flow to the appliance.
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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