High Lockout
E05 on Ravenheat CSI 120

Your boiler has detected an issue with the fan that clears exhaust gases, preventing the system from starting 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

Problem with fan – possibly no signal

What causes this fault?

This fault occurs when the boiler's main computer cannot confirm that the fan is spinning at the correct speed to safely expel exhaust fumes. The most common reasons are a physical failure of the fan motor, a loose connection in the wiring, or a fault on the control board that prevents power from reaching the fan.

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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