High
7.iv on Chaffoteaux Celtic 2 24 Rsc

Your boiler is leaking internally, which is causing pressure to build up and trigger a safety drain to prevent damage.

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.

Technical description

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

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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