High
F34 on ECA Confeo Premix HCH

Your boiler has stopped working because the electrical power coming from your mains supply has dropped too low for it to run 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 (blocking) — supply voltage falls below 170V; notify ECA authorised service

From this model's manual
Verified against the Eca Confeo Premix Hm installation & service manual, page 42.
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

F35View →F36View →

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