High
25. on Remeha Quinta 30

Your boiler is overheating because it cannot move the hot water away fast enough, causing it to shut down to prevent damage.

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

Maximum water temperature. Rise in flow temperature too fast. Check: circulation pump, water flow through the unit, and water pressure (0.8 bar min).

From this model's manual
Verified against the Remeha Quinta 30 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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