BoilerFaultCodesYour boiler has stopped working because the electrical power supply coming into your home is currently too low for the system to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Supply voltage under 170V
What causes this fault?
This fault occurs when the electrical supply entering the boiler drops to a level that is too weak to power the internal components safely. The most common reason is an external issue with the local power grid, but it can also be triggered by a faulty control board inside the boiler that is misreading the incoming voltage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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