Low
b5 on Remeha Avanta 28c

Your boiler is simply taking a short, scheduled break because the water in your radiators has already reached the temperature set on the dial.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Control stop from 3 till 10 minutes: appears if the set flow temperature (t1) has already been reached and the heating demand still exists.

DIY fix possible

Check if your thermostat or boiler temperature dial is set to a comfortable levelEnsure your radiator valves are fully open to allow heat to circulateWait 10 minutes to see if the boiler restarts automatically once the water temperature drops

Find a Gas Safe engineer
Search the official register →

Related fault codes

b8View →

Related guides you might find useful

Radiators cold at the bottom

Sludge build-up — needs flushing, not bleeding.

Read →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →