Cannot turn heating on

[liteman]

I have a 2nd Generation (I think) Nest Learning Thermostat. 3 days ago I turned the heating on for the first time since the summer and it worked fine. I only used it for a couple of hours and turned it off. Today, when trying to turn the heating on I get nothing. The boiler comes on, but the valve that selects either hot water or hot water + heating does not move to the  hot water + heating position. It is only 18months to 2 years old and obviously worked 3 days ago. How do I reset the system to try to get it working again.

This might be a bit of a red herring, but 3 days ago I installed a VPN, which I thought might have been the cause, so I have uninstalled it which has made no difference.

Any help would be greatly appreciated.

[liteman]

This is a small addendum to my first post. I have realised that the heating does come on, but after 4 or 5 minutes it goes off. I have tried a restart on the thermostat but it makes no difference.

[liteman · Accepted solution]

Problem now sorted. It was a duff valve 

[Markjosephp]

Hello liteman,

Thanks for posting and for keeping us in the loop on what you've done to have your concern rectified—give yourself a pat on the back for a job well done!

If you have any other questions or concerns, feel free to start a new thread. We're here to help.

Regards,
Mark