BoilerFaultCodesTechnical description
Dirt on valve seat of Honeywell control.
What causes this fault?
This fault occurs when microscopic debris or grit becomes trapped within the gas valve mechanism, preventing it from forming a tight seal when the boiler switches off. Because the valve cannot close fully, a small amount of gas continues to leak into the combustion chamber, which creates a significant safety risk. The most common reason is the age of the internal components or particulates entering from the gas supply pipework.
Engineer required
This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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