High
80 on Alpha Intec 50CS

Your boiler has detected an internal electrical problem that is preventing it from safely opening the gas supply, so it has shut down to protect your home.

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

Block - gas valve driver issue - A fault has occurred on the PCB function that controls the gas valve

From this model's manual
Verified against the Alpha Intec 50cs installation & service manual, page 49.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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