High
24. on Remeha Quinta 30

Your boiler is confused because it detects that the water flowing out is cooler than the water flowing in, which is the opposite of how it should be working.

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

Temperature sensor fault. a. Flow and return temperature sensors mixed up. b. Flow and return connections mixed up. c. Water flow in D.H.W. mode not correct.

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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