Thermostat not closing contact with the boiler

[JoeK]

I have three nest thermostats their ages vary. They were all working during the summer and in the fall I put them in the off position for about two weeks.  Yesterday I changed them to the heating position and only one of the two works. The other two will not close the circuit to operate the zone valves.  The screens will turn orange but not click/close the circuit to energize the zone valves.   I check the voltages and there is 27 volts and if I close the circuit by connecting the wires manually the zone valves operate.   I have rebooted both thermostats and no change.  I have a forth Nest thermostat that is defective due to failing to connect  to the internet I kept as a spare.  I placed it in service at one of the two locations  and the zone valve sprang into action.   Given the above I believe that I need to replace the thermostats under warranty. 
please let me know how I should proceed. 
Thanks

[Markjosephp]

Hello JoeK,

I'm sorry to hear about the issues that you're having with your 2 Nest Thermostats being unable to send signal to your zoning valves to close. I'm here to help. 

A few questions to narrow it down: what kind of Nest Thermostats do you have? Also, do they have a C wire connected?

Looking forward for your response.

Thanks,

Mark

[JoeK]

The thermostats are the more expensive ones with the stainless steel outer cover.  Yes there is a C wire.  They previously worked flawlessly in the heating and cooling cycles.   If I leave the base plate in place and just replace the body of the thermostat with a spare same model nest thermostat. It energizes the zone valve.   I did a total reboot of the thermostats and that didn’t resolve problem.   I think it is an internal problem in the thermostats. 

My neighbor was the same problem with his thermostats and ended up replacing them with an alternate brand.

[Markjosephp]

Hi JoeK,

Thanks for trying to find a fix.

We'd like to know more about this. Please fill out this form so we could investigate further.

Let me know once you're done.

Regards,

Mark

[JoeK]

I will fill out the form but as an update one of the two thermostats will be covered under the nest warranty per a discussion with a nest service tech. But the other thermostat will not be covered since it is beyond the warranty period. I’m happy that nest at least is covering one of the thermostats but unhappy that 3 of the four thermostats that have paid for has had a uncorrectable problem.  The nest thermostats are at top of the cost scale and should be more reliable.  When they work they work they are great but when they go bad there is no way to repair them. The best. Joe

[Markjosephp]

Hi there,

We haven't received your form yet, but I appreciate you posting and updating us that you were able to get in touch with our team and discuss the issue you experienced with your Nest Thermostats. Please fill out the form so we can check more options for you.

Keep me posted if you're done or if you have any other questions or concerns.

Thanks,

Mark

[Markjosephp]

Hi JoeK,

I know it has been a while but I wanted to ensure that everything is covered here. Were you able to fill out the form? We're here to help.
 

Best,

Mark

[Markjosephp]

Hello JoeK,

It has been a few days since the last reply, and I am going to lock the thread in 24 hours. If you have any questions, please feel free to create a new post.

Best regards,

Mark