topic Re: Furnace not Turing on in Nest Thermostats

Furnace not Turing on

Confused84 — Sun, 29 Dec 2024 21:17:03 GMT

So I’m at a loss. My furnace is LP, one stage from 2020. It works fine with my Honeywell thermostat. I only have R and W for wires. I connected the gen 4 and it will say it is heating the house but my furnace is not running. I get no error codes. If I turn the furnace off and on it runs for 3-5 min and never goes on after that. I know it is something with the thermostat but not sure what. Someone have some valid solutions?

Re: Furnace not Turing on

GabrielaG — Thu, 02 Jan 2025 18:03:13 GMT

Hi Confused84,

Thanks for reaching out to the community. I'm sorry to hear that your Nest thermostat 4th gen is not turning on the furnace. I'm happy to assist you right now.

To get a better understanding of the situation, please help me out by answering the following questions:

When did the issue first occur?
When was the Nest thermostat installed?
Are all the wires of your thermostat seated firmly in its terminals?
Have you done some troubleshooting steps? If so, can you please list them?
Can you please send me a picture of the thermostat wiring?

Any additional details you can provide will be helpful.

Regards,

Gabriela

Re: Furnace not Turing on

Confused84 — Thu, 02 Jan 2025 18:23:10 GMT

This occurred immediately from install.
the thermostat was installed on Christmas Day.
Yes, all wires are firmly seated.
I have not been able to locate many troubleshoot steps in regard to this device. I have changed my air filter to ensure it is good. I have restarted the thermostat and my furnace.
I am unable to send a picture due to my location. I only have Red and white.

Re: Furnace not Turing on

GabrielaG — Fri, 03 Jan 2025 00:25:57 GMT

Hi Confused84,

Thank you so much for keeping me updated and taking the time to answer my questions. I appreciate the information you provided me. I'm happy to continue assisting you right now.

I recommend following the steps below:

Check the thermostat’s settings.

Target temperature
Home & Away Routines and Home/Away Assist settings
Schedule

Check the ends of the thermostat wires; they should be straight, leaving ⅜ of an inch or 10 millimeters of wire exposed.
Check if your HVAC system needs maintenance.

Also, I see that you don't have a C wire connected in your thermostat. The Nest Learning Thermostat 4th gen might work without a C wire, but if you're still having the same problems after doing all the troubleshooting steps, I recommend contacting a Nest pro technician to check if your system needs a C wire to make the thermostat work.

Feel free to keep us posted if you have more questions.

Regards,

Gabriela