Emergency
30 on Daikin Altherma Hybrid EHYKOMB33

Your boiler's safety system has detected a potential electronic fault with the mechanism that controls the gas flow, so it has shut down to keep your home safe.

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 relay fault

From this model's manual
Verified against the Daikin Altherma Hybrid Ehykomb33 installation & service manual, page 30.
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

30-01View →30-02View →

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