Low
S.30 on British Gas 330+

Your boiler is working fine, but it isn't receiving a signal from your room thermostat or programmer telling it to turn on.

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.

What the manual says

Manufacturer manual

No Heating demand from external controls 230V. Check wiring in external controller. Check wiring at Installer Interface.

From this model's manual
Verified against the British Gas 330 installation & service manual, page 47.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that your room thermostat is turned up higher than the current room temperature.Ensure your central heating programmer or timer is set to 'ON' or 'AUTO'.Replace the batteries in your wireless room thermostat if the display is blank or fading.Check that the internet gateway is connected if you use a smart system like Hive or Nest.

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