BoilerFaultCodesTechnical description
An insufficient ionisation current was measured following ignition of the burner
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a steady flame after the burner has successfully lit. This is often caused by a dirty or worn-out sensor probe, a blockage in the drainage system that causes water to 'choke' the flame, or an incorrect ratio of gas and air reaching the burner.
This issue is more frequent in very cold weather, as the condensate drainage pipe can freeze, causing water to back up into the boiler and extinguish the flame.
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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