Google Nest thermostat does not allow heating

[Corina]

My Google Nest thermostat is behaving weirdly. It shows a low temperature (17 Celsius), lets me set it to a higher temperature and says it will take 2 hours for example. But then the heaters don’t get warm at all so the temperature never rises. We are connected to central heating from the municipality via warm water that goes in the heaters. I checked the pipes entering the house and they are warm, but it never gets into the heaters themselves and I think that’s because of the thermostat. 
Did anyone else have the same issue? Any advice?

[Houptee]

How did you wire it up? Did you take before pics of the old Tstat and another of the way you hooked up the wires to the Nest?

Post the pics here so we can see what you did.

[CoolingWizard]

Houptee, this user, Carina, s probably in the UK and is a Nest Thermostat with a HeatLink. These are typically professionally installed.  

Ken, The AC Cooling Wizard

[Corina]

I’m in the Netherlands. My husband installed it and he didn’t take any pictures of the wires before and after. It worked well for more than a year. 

[CoolingWizard]

Your Nest Thermostat is probably using a Nest Heat Link that connects to your heating control system.  You have to have the the Heat link tested to verify that it is initiating a call for heat to the hydronic control system. You to determine if the Heat Link has failed or the Hydronic control system has failed. 

Ken, The AC Cooling Wizard

[Corina]

Thanks Ken! I appreciate the answer. Can you maybe expand on how I do that? Can we do it ourselves or do we need help from a professional?

[CoolingWizard]

Corina,

Sadly I am the United States and do not need the  use of that PowerLink technology.   But here is the basics of the control system. The Powerlink sends power to the control system to initiate the opening of the valves to allow the central heating hot water or steam to enter the domicile.  With a volt ohm multimeter, we need to verify that the powerlink is sending power out of it.  If the PowerLink is forwarding power, the problem lies with the control system and testing of that will require a service professional.  If the powerlink is not forwarding the power, then the problem lies in the powerlink.  

Ken, The AC Cooling Wizard

[Corina]

Thanks for the advice Ken! We did try with a new device and still doesn’t work, so it’s probably a valve. We’re having a professional come and check it.