BoilerFaultCodesYour boiler has no power and is completely unresponsive, likely due to an electrical supply issue or a blown fuse.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check connections and continuity of EMC filter or rectify external fault.
What causes this fault?
This fault occurs when electrical power fails to reach the boiler's internal controls, leaving the unit completely lifeless. The most common reason is a blown fuse in the external wall switch or a surge that has tripped the boiler's internal protection, often caused by a failing component like the pump or fan. In some cases, the interference filter has failed, preventing electricity from flowing through the circuit safely.
DIY fix possible
Check if your home's main electrical consumer unit has a tripped circuit breakerEnsure the boiler's external isolation switch (fused spur) is turned onReplace the 3-amp fuse in the external isolation switch with a new one
Find a Gas Safe engineer
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