Emergency
88 on Alpha Intec 50CS

Your boiler has detected an internal issue with the part that manages the gas supply, so it has safely shut itself down to prevent any risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Block - gas valve control A malfunction of one of the components that control the gas valve has been detected

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

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