BoilerFaultCodesTechnical description
Combustion test alarm during auto-setting
What causes this fault?
This fault occurs when the boiler's internal computer tries to automatically balance the ratio of gas and air but fails to reach a safe or efficient level. The most common reason is that the sensing electrode is worn out or the gas valve is unable to adjust precisely enough to complete the self-test. It can also be caused by an unstable gas supply or a blockage in the flue affecting the air intake.
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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