BoilerFaultCodesTechnical description
An ionisation current was measured before the burner started
What causes this fault?
This fault occurs when the boiler's internal sensors detect a flame or electrical current before the ignition process has even begun. The most common reason is a buildup of carbon or moisture on the sensing electrode that tricks the system, or a faulty gas valve that is slightly leaking fuel into the combustion chamber.
This issue can be more frequent during periods of high humidity or heavy rain, as moisture entering the flue can interfere with the sensitivity of the electrical flame-sensing components.
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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