2 4. High

Remeha 2 4. Fault Code

Also written as 24 — same fault.

The Remeha 2 4. fault code means: your boiler has detected that hot water is moving in the wrong direction or the temperature sensors have been confused, causing the system to shut down for safety.. It appears on 3 Remeha models in our database.

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: 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.

What causes the Remeha 2 4. fault?

This fault occurs when the boiler's internal sensors detect that heat is flowing in the opposite direction than expected, often because the flow and return pipes are behaving incorrectly. The most common reasons are a blockage in the heat exchanger, a failing diverter valve that is sticking, or the temperature sensors themselves becoming faulty and giving the control board conflicting information.

This issue often comes to light in autumn when the central heating is turned back on after months of only providing hot water, putting stress on the diverter valve.

Typical repair cost £120-250 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Remeha models that show the 2 4. fault code

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

Source

Remeha 2 4. 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