My boiler comes on intermittently when the thermostat is turned down below zero degrees.
It is all running fine and domestic hot water is OK too, when you turn the heating thermostat to demand he boiler kicks in and works fine and the same when it is turned down it kicks off ok but after a short period the boiler starts to run,the green light comes on and runs for 5 to 6 minutes at low temperature and then goes off again.
If you turn a tap on for hotwater then it all works fine but goes back to doing what is explained above..

Any ideas anybody please. A faulty temp sensor or pressure

Dave, November 2016

I thought I'd be alittle less sarcastic than my co-contributor.

You have, I assumed, checked the manual. The one I looked at I found at http://www.glow-worm.co.uk/glow-worm/cxi-range-157150.pdf

I saw this:

11.9 Pump Exercise Program
After a power cut or every 24 hours in holiday mode the three way valve will switch and the pump will run to prevent the components from sticking. This will also occur during normal operating if there is no domestic or central heating demand for more than 24 hours.

Thefre is also a pre-heat function that may be running.

Having a 30CXi myself, I can confirm these do run occasionally up for a few moments, even when there is no demand.

XXX, November 2016

Sounds like it is doing its job. Leave it alone!

No faulty temp sensor or pressure just the end user as usual., November 2016