High Lockout
17 on Ravenheat Csi Primary

Your boiler has stopped working because the fan is not receiving the correct electrical power needed to safely clear exhaust fumes.

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.

Technical description

Possible issue with fan voltage

What causes this fault?

This fault occurs when the boiler's main control board detects an incorrect voltage being sent to the fan motor. The most common reason is that the fan components have worn out and are drawing too much power, or the control board itself has developed a fault and can no longer regulate the electricity properly.

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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