Technical description
Flame detection error (parasite flame)
What causes this fault?
This fault occurs when the boiler’s internal control system thinks a flame is present even though it shouldn't be burning. The most common reason is a sensor that has become dirty or faulty, or a gas valve that is slightly leaking and allowing a small amount of fuel to keep a flame going. In some cases, the electronic control board may simply be misreading the electrical signals from the burner.
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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