topic Re: Just installed and cool setting blows heat; heat blows fan in Nest Thermostats

Just installed and cool setting blows heat; heat blows fan

MST7001 — Sat, 06 Aug 2022 23:48:57 GMT

Hello,

I just replaced a Honeywell unit with the Nest Learning unit...carefully wired everything and double checked. During the test and in regular cooling mode, it blows only heat. When in heat mode, it blows the fan, not heat.

I just reinstalled the old unit and it's blowing cold so doesn't seem to be an issue with the a/c unit. Any suggestions would be appreciated - thank you!

p.s. the Nest image below was after I tried it with the white (W2) wire disconnected, which I saw as a possible solution in the help. Still same result - only heat comes from the Cooling mode.

old wiringNest wiring. I tried the white in W2 and without plugged in, as shown.

Re: Just installed and cool setting blows heat; heat blows fan

AZAllen — Sun, 07 Aug 2022 02:42:32 GMT

We're having same issue with both Nests we installed today. Downstairs just blowing air - house getting warmed. upstairs blowing hot then warm air. Resintalling orginal thermostats based on what we've read here online.

Re: Just installed and cool setting blows heat; heat blows fan

MST7001 — Sun, 07 Aug 2022 03:00:52 GMT

I think I figured it out: the brown wire that appeared to be on "W" in the old unit actually was going to "OB" since it functions as a heat pump, not a conventional unit. I switched it to that and it works perfectly now - blows cold air. Might want to give that a try -

Re: Just installed and cool setting blows heat; heat blows fan

MelbaDT — Thu, 11 Aug 2022 05:41:11 GMT

Hey folks,

MST7001, thanks for posting and for keeping us in the loop on what you've done to have your concern resolved. We're glad to hear that it is now working with your HVAC system as it should.

AZAllen, I'm sorry to hear about your experience with your Nest thermostat. If you have a heat pump like MST7001, please try his suggestion. If not, provide a clear photo showing the terminal labels of your original thermostat wires as well as your Nest thermostat.

Best,

Melba

Re: Just installed and cool setting blows heat; heat blows fan

Ryan_G — Sun, 14 Aug 2022 13:11:39 GMT

Hey everyone,

I'd like to jump in here and check if you've seen Melba's response. Let us know if you need more help by replying to this thread.

Thank you for your help, Melba.

Regards,
Ryan

Re: Just installed and cool setting blows heat; heat blows fan

Ryan_G — Tue, 16 Aug 2022 05:29:13 GMT

Hey there,

Thanks for being here in the Google Nest Community.

I'd like to bump in here and make sure that you’ve seen our response.
Please let us know if you have any other questions or concerns as I will be locking this thread in 24 hours.

Have a great day.

Best regards,
Ryan