BoilerFaultCodesYour boiler has shut down because electronic interference or a faulty internal circuit board is preventing the burner from starting safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked. Strong interference (EMC) field nearby; alternatively boiler coding card or main PCB faulty. Cause: Remove EMC interference. If the equipment will not restart, check the boiler coding card and replace, or replace the control unit.
What causes this fault?
This fault occurs when the boiler's internal computer receives garbled or 'noisy' signals that prevent it from safely managing the burner. It is typically caused by electronic interference from a nearby appliance or a physical defect in the PCB or its unique coding card. Essentially, the boiler has lost its ability to verify its own settings and shuts down as a safety precaution.
DIY fix possible
Turn off any nearby large electrical appliances or power tools that might cause electronic interference.Press the reset button or turn the boiler off and back on at the fused spur.If the fault persists after a reset, you must call a Gas Safe registered engineer.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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