Alpha Neon A and B Flashing on and off at the same time Fault Code: What It Means & How to Fix It

Your boiler has detected an issue with safely removing exhaust gases outside, so it has locked itself out to prevent any risk.

Typical repair cost for the Alpha Neon A and B Flashing on and off at the same time fault is £150-350 including labour.

What the manual says

Manufacturer manual

Blocked flue or fan fault.

From this model's manual

Verified against the Alpha/Alpha Alpha Cb24 installation & service manual.

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Boiler cover options

A cover plan would handle faults like Neon A and B Flashing on and off at the same time: no call-out fees, no surprise bills.

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