Nest 3rd generation not turning on boiler

[grant95783]

Installed this and have not had success getting it to call the boiler. All the wiring checks out and no errors to see. If I manually connect W1 and Rh the boiler operates. Not sure why the Nest is not able to do the same thing to kick the boiler in. My old Honeywell thermostat still works if I switch it back. This is driving me insane as both old thermostat and manual behave the way I need the Nest to work. No clue what is causing this issue. I've provided some pics but don't think they will be that helpful. Note I've also checked the equipment wiring, and turned off safety temperature. These were suggested by others. As far as the system shows, there are no obvious signs.

[Houptee]

You have a "dual transformer" system.

The boiler has its own transformer and the AC has its own transformer.

This kind of setup the Nest gets its power to run and charge from the AC system RC and C.

It only acts like a switch for Rh and W and should not use those to power the Nest.

Is the AC system power turned on so the RC is getting power and is the C wire coming from the boiler or the AC system? It should be C coming from the AC system to work correctly.

[aatienza]

Hey grant95783,

Checking in — we hope you've got the answer you're looking for. Let us know if you have more questions in mind.
 

I appreciate the help, Houptee.

Thanks,

Archie

[aatienza]

Hey there,

I just wanted to follow up to see if you still need our help. Please let us know as we would be happy to answer any questions you may have.

Thanks,

Archie

[grant95783]

Hey, this problem still exists. I posted in my town FB group who have similar houses and heating setups. One had success talking to a rep and trying various things apparently. Another person had no success and got their hardware replaced and then it worked. I want to try talking to a rep and if that doesn't work it could be the hardware. Still open to help here if there are other ideas.

[Jake]

Hey there,

Apologies for the delayed response. I wanted to follow up and see if I could be of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further. 

Best regards,
Jake

[grant95783]

Hey Jake,

I'm still having this issue. The boiler is not being activated as it should when the heat setting is turned on. This works when I connect the Rh and W wire. The unit is completing the switch. I think this may be a hardware issue. Do you have any other tricks I have not tried yet? If not, this should still be covered under warranty. Can you let me know how I could do that?

[zoeuvre]

Hello everyone,

I wanted to stop by and see how I could help. Can you help me with your Nest Learning Thermostat's power reading?

1. Open the Quick View menu, press the thermostat’s ring.
2. Choose Settings.
3. Turn the ring to highlight Technical Info then press the ring to select it.
4. Select Power. 
   • VOC
   • VIN 
   • IIN

I'll look forward to your response.

Thanks for the help here, Houptee, Jake, and Archie. 

Best, 

Zoe

[Jenelyn_O]

Hi grant95783,

I wanted to follow up if you still need help. Please let me know if you’re still having any concerns or questions from here, as I would be happy to take a closer look and assist you further.

I appreciate your help, Zoe.

Regards,
Jenelyn

[Jenelyn_O]

Hello there,

We haven't heard from you in a while so we'll be locking this thread if there is no update within 24 hours. If you need assistance or want to discuss topics, feel free to start a new thread.

Thanks,
Jenelyn

[grant95783]

Hey Jenelyn,

Please don't close. I have to take off my old thermostat and put the nest back on to get the information requested. Since the Nest wasn't working I had to use my old thermostat still. I'll provide this today and see if y'all can help. I believe it is a hardware issue but I'm hoping y'all have a trick up your sleeve. The reason I say hardware is that I've tried most things already. The only person I've seen get this fixed got a new unit and it worked. Not big data by any means, but a solution that may be the last option.

[Jenelyn_O]

Hi grant95783,

Thanks for getting back to us. Please feel free to send it to us. I'll keep this thread open. 

Best,

Jenelyn

[grant95783]

Hello,

The readings you requested are:

• VOC: 33.49
• Vin: 33.49
• lin: 200mA

Can you let me know if this is somehow irregular?

[Jenelyn_O]

Hey grant95783,

Thanks for sharing the information above. I'm sorry for the delay. Based on the readings of your VOC, VIN and IIN, they're fine. Could you please share with us the readings of your Nest Thermostat battery? Also, please go to your thermostat Settings then look for Equipment and check for wiring diagrams and any messages or code there. 

Keep me posted.

Regards,

Jenelyn

[grant95783]

Thanks Jenelyn.

Battery is 3.922V

Equipment sensed on: W1-Y1-G-C-Rc-Rh

No messages or codes here.

[Jenelyn_O]

Hi there,

Thanks for the follow up information! Your Nest Thermostat power readings are good, and to the fact that your thermostat detects all of the wires, your system should work properly. How's your boiler now? Does the issue persist? 

Best,

Jenelyn

[grant95783]

I called Nest support and we tested a few things. The rep determined that the Nest Thermostat was likely the issue. As such, I am getting a new one that should hopefully resolve the issue.Appreciate the help along the way.

[Jenelyn_O]

Hi grant95783,

Thanks for the update. I'm glad to hear that it is sorted out and you're getting a replacement. If anything comes up, please let us know by creating a new thread so we can assist you from there, as I'll be locking this thread after 24 hours.
 

Best,

Jenelyn

[grant95783]

Thanks for this context. You are correct and this was a possible issue before. I ran a new C wire that is from the AC. It works for providing power and the fan and AC work.

This did not resolve the heat problem unfortunately. It still does not close the switch when the heat is turned. It is such a simple thing that isn't working for some reason. Thanks for the reply