Emergency
04 on Alpha E-Tec 20S

Your boiler has lost electrical communication with its internal gas valve, which stops it from safely supplying gas to heat your home.

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

Gas valve electrical connection fault

From this model's manual
Verified against the Alpha/Alpha E Tec S installation & service manual.
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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Related fault codes

02View →03View →24View →

All 29 fault codes on the E-Tec 20S

Seeing a different code? Every code this model can display, in one place.

0102030506081012151620232425293137384345475160617576nSr

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