High
Mains On neon not lit on Ideal Classic FF

Your boiler has no power, which means it cannot turn on to provide heating or hot water.

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.

What the manual says

Manufacturer manual

No mains voltage to the boiler, blown EMC filter, or external fault.

From this model's manual
Verified against the Response Ff80 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the electrical supply to the boiler is interrupted or fails to reach the internal control system. The most common reason is a blown fuse or a failed component like the EMC filter that has blocked the incoming power to prevent further electrical damage. It can also be caused by an external issue, such as a tripped circuit breaker in your home's main fuse box.

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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