High
F34 on ECA Proteus Premix 24 HCH

Your boiler has detected that the electrical supply voltage coming from your home's mains is too low to run it safely.

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

From this model's manual
Verified against the Eca/Eca Proteus Premix 24 Hch 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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Related fault codes

F33View →F35View →

All 28 fault codes on the Proteus Premix 24 HCH

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

E01E02E03E05E08E09E12E15E16E17E18E21E33E35E80E82F07F13F37F39F40F47F50F51F52F53F81

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