topic Re: Nest thinks I have a heat pump in Nest Thermostats

Nest thinks I have a heat pump

Hornezd — Wed, 17 Jan 2024 10:26:03 GMT

I set up our nest over the summer. We have forced air A/C and gas heat. The A/C has worked without issues. We also have radiant heat in the house, controlled by a separate thermostat, that we've been using to heat the house. During a particularly cold snap, we turned on the forced air and I discovered that the system reads as having two heat sources, one being a head pump.

The original wiring had a jumper from Rc to Rh and connections to both W and W2 as well as O. The set up app has me connected to Rc, O/B and W2.

I don't see a way to change my heat source from within the nest app.

Thanks

Re: Nest thinks I have a heat pump

Markjosephp — Sat, 20 Jan 2024 16:58:44 GMT

Hello Hornezd,

It seems like you've encountered an issue with your Nest setup, specifically with the detection of multiple heat sources. To address this, you may want to check the wiring and settings on your Nest Thermostat.

Firstly, it's good to hear that your AC has been working well. Regarding the radiant heat and forced air system, the presence of a heat pump might be causing the confusion in the Nest thermostat's detection. Here are a few steps you can take to troubleshoot:

Ensure that the wiring matches the recommended configuration for your specific HVAC system. It sounds like there might be an issue with the jumpers and connections.
Open the Nest app and go to the thermostat settings. Look for an option that allows you to specify your heat source.
- Check if there's an option to select the type of heating system you have (e.g., forced air, radiant heat, heat pump) within the app. This could be under the equipment settings.
If your system has a heat pump, ensure that the Nest thermostat is configured correctly for it. Some systems require specific settings for heat pump operation.
Share with us your old thermostat and Nest Thermostat's wiring setup. This would help us check its configuration.

I'll look forward to your response.

Best,
Mark

Re: Nest thinks I have a heat pump

Hornezd — Sat, 20 Jan 2024 21:43:33 GMT

The radiator is controlled by a separate thermostat. I haven't braved converting that one to a Nest yet, but I intend to. How to get two different systems controlled by different Nests in different parts of the house

The current nest controls just the forced air/heat. Unfortunately it appears that I can't upload my photo of the original configuration so I'll describe as best I can:

C - connected	Rh - connected by jumper to Rc
O - connected	Rc - connected
B - empty	G - connected
W - connected (wire was brown)	Y - connected
W2 - connected (wire was white)	Y2 - empty

I connected the Nest in a similar fashion and it registered the forced air but believed the heat to be a heat pump.

I was unable to select forced air heat as an option, even in pro mode.

My next move was to change my connection configuration to:

Y1 - connected	W1 - connected
Y2 - empty	W2/Aux - empty
G - connected	C - connected
O/B - empty	* - empty
Rc - connected	Rh - empty

So the jumper was removed between Rc/Rh, W2 is empty, the brown wire that was connected to W is no longer connected to anything, and the orange wire that was connected to O is no longer connected to anything.

Once I did this, the heat started to work. I do wonder if the A/C will work come the warmer months..

Re: Nest thinks I have a heat pump

Markjosephp — Sat, 03 Feb 2024 22:11:36 GMT

Hey there,

I'm sorry for the late reply. If you've made changes and the heat is working but you're concerned about the air conditioning, it's a good idea to test the cooling functionality to see if it's functioning correctly. Also, it would be easier for me to visualize it with a photo.

To insert an image in a post:

Reply to this post.
Click Insert Image (camera icon).
Choose an image source location.
Follow the on-screen instructions.

Keep me posted.

Regards,
Mark