BoilerFaultCodesYour boiler has stopped working because its internal computer and burner control system are failing to communicate correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: BMM fault.
What causes this fault?
This fault occurs when the boiler's main control board loses its digital connection with the burner management module, which acts as the 'brain' for the firing process. It is typically caused by a hardware failure within the internal circuitry or a loose connection in the wiring harness that links these two critical components. Without this constant data flow, the boiler cannot safely coordinate the ignition and heating process.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F019 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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