Emergency
7.iv on Chaffoteaux Celtic 24 HE

Your boiler is leaking internally between the heating and hot water systems, causing water to pour out of the safety pipe outside.

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

Safety valve discharges - Secondary heat exchanger (water to water) internal water leak

From this model's manual
Verified against the Chaffoteaux Celtic 24 He 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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