High Lockout
False Flame Fault on Potterton Performa SL HE 9 2

Your boiler thinks a flame is present when it shouldn't be, causing the system to shut down for safety purposes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Automatic Lockout. A flame is detected before an ignition attempt or unstable flame during run period.

What causes this fault?

This fault occurs when the boiler's control system detects an electrical signal from the burner even though it hasn't commanded the gas to ignite yet. The most common reasons are a contaminated flame sensor sending a rogue signal, a gas valve that is leaking slightly, or a fault within the main circuit board that is misinterpreting electrical noise as a 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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