How much does it cost to fix Remeha error code b25?

Typical repair cost for the Remeha b25 fault is £150-300 including labour.

b25 High

Remeha b25 Fault Code

Q: What does the Remeha b25 fault code mean?

Your boiler is detecting that its internal water temperature is rising much faster than it should, so it has shut down to prevent damage.

Also written as B25 — same fault.

The Remeha b25 fault code means: your boiler is detecting that its internal water temperature is rising much faster than it should, so it has shut down to prevent damage.. It appears on 2 Remeha models in our database.

Technical description: Temperature rise too fast (dT/dt)

Typical repair cost £150-300 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Remeha models that show the b25 fault code

Click a model for the full fault code list and model-specific repair notes.

Quinta 30 Repair: £150-300
Quinta 85 Repair: £150-350

Source

Remeha b25 fault code information on this page is sourced and cross-checked against the official Remeha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026