High Lockout
E35 on Ideal Mini C32

Your boiler has sensed a flame after it should have gone out, or before it has even started, causing it to shut down for safety.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

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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