Wyze Thermostat Problem - AC on with Heat

I installed the wyze thermostat yesterday and it is working, but turns on my AC when it should be running just heat. I have natural gas and forced air. Please let me know what to try to fix this. Thanks for the help!

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Also, I did not use the C Adapter because I had a C wire from the wall, could that be an issue? I have not checked my furnace board wiring.

Yes, check your furnace wiring. Normally, when the A/C is on during heat, either the compressor is hooked up wrong, or you have told wyze you have a heat pump. When you set up the outputs on your phone, did you select gas heat and normal A/C?

This is my furnace wiring. I set it up as natural gas and forced air.

There are 2 sets of wires connected. Looks like an extra white (connected to C) and red wire (connected to Y) from the 2nd set of wires. I’m lost.

My setup is similar to yours. I have two wires connected to C, and two connected to Y.
After installing my Wyze Thermostat, when my heat comes on, the fan is on high … which is usually reserved for A/C, since cold air is denser. A couple of minutes later, the fan switches itself to low.
While my blower was on high, I went outside to check if the A/C was on, and it wasn’t (thankfully).

I’m thinking of disconnecting my C wire and using my C adapter instead.

The extra wires you see connected to the C (white) and Y (red) terminals are going to the A/C unit. You can disregard those for the purpose of connecting the Wyze thermostat. I am not sure why your A/C runs when it should use the heater. It sounds like wires are crossed somewhere, but from your pictures it looks like it’s all connected properly. Have you tried to reset the thermostat to factory settings and re-add it to the app?

Yes, just did a factory reset and added the thermostat again. I figured those extras were for the AC unit. I didn’t use c adapter from Wyze, but don’t think I should have either… still is running AC with heat at the moment.

You have the blue C wire and the four others. I know it’s absolutely not helping you, but I have the same five-wire configuration you have and it’s working for me. It sounds like your W and Y wires are somehow switched in the thermostat.

When you re-added the thermostat to the App, did you get through the test phases correctly?

When it tested the heat it takes a while to get hot. Seems the AC is fighting against it. When it tested the AC it worked fine.

I tried disconnecting the Y1 from the thermostat and trying to run it. It runs, but for some reason the AC was still running with the heat.

To troubleshoot I would put the old thermostat back and see if that works as it should. If it does there may be some wiring problem with the Wyze thermostat? Otherwise, this has me stumped…

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I suspect my A/C compressor is running the same time my heat is on (although my outside fan is not spinning). In addition to my furnace using its faster blower speed, the air takes a good while to get hot.

I am going to try to turn off the A/C circuit breakers and see what my furnace does when I turn the heat up. You might want to try this, too.

EDIT: I turned off my A/C circuit breakers, and my furnace is still behaving the same. But one thing I noticed is that with my old thermostat, when I turned up the heat, the furnace would heat up for a minute or so before the blower came on, so the hot air came through the vents right away. With my WYZE thermostat, the blower kicks in the second I turn the heat up, not giving the furnace chamber a chance to heat up first.

It seems that something is not wired right if your compressor is on while the heater runs. It could be that they Wyze thermostat actually exposes that problem. But I am not an A/C tech in any sense, I just watched a bunch of Youtube videos on the topic. It may be time to have your wiring checked by a licensed professional?

Thanks. I said I suspected that my compressor was running because my furnace’s blower went into high-speed mode, and the air took longer than usual to heat up. But I went and tripped the circuit breakers for my A/C, and turned on the heat again. The air took awhile to heat up again, but there is no way my A/C compressor could be on because I tripped the circuit breakers.

But as I explained in my previous post, with the WYZE thermostat, air starts blowing the second I raise the temperature. With my old thermostat, the furnace would heat up the chamber for a minute or so before turning on the blower, so the heat was instant.

The only thing that bothers me at this point is why my furnace blower is on high speed for heat, when it should be on low speed. High speed is only needed for A/C because cold air is denser. Now when I turn on the heat, the furnace blows at high speed and then with about a minute remaining it switches itself to low speed. Something’s not right.

I think i have seen this too. Wyze thermostat is sending a fan on control instead of fan auto control. I noticed that on my Honeywell thermostat it has coast to heat and cost to start. But with wyze fan turns on immediately

Interesting. I noticed that over here, with the Wyze thermostat the fan starts running when the thermostat clicks on, but then stops, but it starts again a while later once the furnace burner is on.

I ran into the same issue with Wyze thermo turns on heat and AC at the same time. I have not figured it out.

I just hooked up my old original thermostat the same as the original picture and it works as it should. AC stays off for heat and even runs the furnace 20-30 seconds before the fans kick on to push warm air to the vents.

So I have some issue with the Wyze thermostat. No new info but confirmed it will not operate the same with the same wiring at this moment.

This is because wyze controls the fan. if your furnace is smart enough, it can control the fan instead. to test this out, just disconnect the G wire, and make sure that both heat and cool still work.

Are you sure it’s running the AC at the same time? The wyze runs the fan early in the heat cycle, and it will blow cold air for a while until your heat exchanger heats up. It annoyed me enough that i disconnected the G wire on my wyze and just let the furnace control it’s own fan speeds.

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I believe it is running AC because my outside AC unit turns on and fan blowing with heat on for the wyze thermostat but does not turn on for the original thermostat for heat.