High Lockout
F019 on Intergas Xtreme / Xclusive

Your boiler has encountered an internal communication error between its main control boards, causing it to shut down for safety.

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

BMM error

What causes this fault?

This fault occurs when the boiler's internal computer chips lose the ability to speak to one another, preventing the system from confirming it is safe to fire. The most common reason is a technical glitch or a physical failure within the main control boards or the wiring that connects them. Think of it like a lost connection between a computer and its screen that forces the whole system to freeze for safety.

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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Related fault codes

F000View →F001View →F010View →

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