Low Information
4-5 on Remeha Gas 350

Your boiler is notifying you that it has successfully transitioned to its second, higher stage of heating output.

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

Operating signal stage 2

What causes this fault?

This code is not actually a fault, but a status update showing your boiler has increased its heat production to meet a higher demand. It occurs when your heating system realizes the building needs more warmth than the initial low-power setting can provide. The boiler is simply communicating that it has opened its gas valve further to run at full capacity.

This notification is more likely to appear during the winter months when outdoor temperatures drop and your home requires maximum heat output to stay warm.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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