Low
S.00 on Vaillant ecoTEC plus Aquaplus

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water, so it is working exactly as it should.

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

No heat demand (heating operation)

DIY fix possible

Check your room thermostat to ensure it is set to a temperature higher than the current room temperatureEnsure your heating programmer or timer is set to 'on'Check that your hot water demand is active if you require a tank refill

Find a Gas Safe engineer
Search the official register →

Related fault codes

S.01View →S.02View →S.03View →

Related guides you might find useful

No hot water but heating works

Almost always a stuck diverter valve on combis.

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 →