topic Re: Fan only w/o cooling hack? in Nest Thermostats

Fan only w/o cooling hack?

Road2FIRE — Sun, 28 May 2023 13:47:58 GMT

Hi, I'm been searching the forum for a hack re: the issue of being able to run the fan without the AC turning on. I just want only the fan to run and I don't want the AC to turn on. The only way I think I can assure that my AC doesn't turn on is by setting the cool temperature to the highest cooling level. However that defeats the purpose of a "learning" thermostat because it's going to think I love to keep my house at a really high temperature.

It seems like this is very basic functionality that all thermostats should have. I replaced my clunky Trane thermostat that had a fan-only mode w/o ever triggering cooling, so I'm so surprised that the NEST doesn't have an option.

Am I missing a hack to solve for this?

BTW, I have a Gen 3 Learning w/ a dedicated fan wire.

Thx

Re: Fan only w/o cooling hack?

Markjosephp — Thu, 01 Jun 2023 18:25:57 GMT

Hello Road2FIRE,

Thank you for taking the time to let us know about your inquiry.

You can run your system's fan independently of heating or cooling. So your system doesn't need to be actively heating or cooling to run the fan. Please take a look at this article with the fan control settings and let us know if you have more questions.

Regards,
Mark

Re: Fan only w/o cooling hack?

Road2FIRE — Thu, 01 Jun 2023 18:48:50 GMT

Thanks. But that really doesn't solve the issue. I still have to put the thermostat in Cool mode AND increase the temperature to a high number (i.e., 89 degrees) so that the AC compressor doesn't turn on. There really should be three settings -- Heat, Cool, and Fan.

By having to set the thermostat to Cool, I have to manually adjust the set schedule for when I want to run my AC and it defeats the purpose of the "learning" feature of the thermostat.

Or am I not understanding the Nest controls?

Thx

Re: Fan only w/o cooling hack?

Markjosephp — Thu, 01 Jun 2023 19:21:59 GMT

Hey there,

I understand that settings can be confusing. To be sure that the fan is working independently, please run a system test on your actual thermostat's Equipment settings > Test. This will activate your fan alone and check to see if it's working. If it does, tap and hold your thermostat screen for 3 seconds to re-route you back to the temperature screen, then go back to the Quick View menu; you should see the Fan icon at the top. Tap it and try running the fan on it.

Keep me posted.

Best,
Mark

Re: Fan only w/o cooling hack?

Road2FIRE — Thu, 01 Jun 2023 20:21:28 GMT

Thanks for replying. Using the test method that you outlined, the fan does turn on independently. However when I choose Fan from the main menu, it forces me to choose a mode (Cool) to turn on the fan. And because my temperature was set low (72 degrees), it turned on the AC too. So the only way to override that is to set the temperature high.

I'm guessing Google never coded for a fan-only mode, which is unfortunate because it's basic functionality that every other thermostat has. Just to keep the air flowing throughout my house I'd love to run the fan constantly -- or at least run it on a schedule. But that still won't work because the schedule I have will trigger the AC to turn on eventually because it's set to adjust to 72 degrees each day. My thermostat will learn incorrectly then.