High
37 on Alpha Intec2 30SE

Your boiler is failing to start because it is not receiving the correct amount of electrical power from your home's mains supply.

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

Low supply voltage. Insufficient supply voltage to operate boiler

From this model's manual
Verified against the Alpha Intec2 25 28xe 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 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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