High Lockout
Neon2 on Ideal Classic FF

Your boiler has detected an issue with the fan that safely removes exhaust gases, meaning it cannot start up for safety reasons.

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.

Technical description

Fan voltage indication

What causes this fault?

This fault occurs when the boiler's control center sends power to the fan but does not receive the necessary electrical feedback to confirm it is spinning correctly. The most common reason is that the fan motor has burnt out or become seized, preventing it from clearing toxic exhaust gases from the system.

This fault can be more common during the first cold snap of autumn, as mechanical parts like fans can seize up after being idle or used infrequently during the summer.

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.

Find a Gas Safe engineer
Search the official register →

Related fault codes

Related guides you might find useful