Hello,
I have Bryant HVAC system and have 4 wires connected to ABCD terminal and previously tried Nest and it was not compatible.
As per the Thermostat manual it shows the following:
A-Green = Data A
B-Yellow=Data B
C-White=24VAC (Com)
D-Red=24VAC (Hot)
I have attached the diagram of the Thermostat wiring. Can anyone please confirm if Wyze Thermostat will work for me?
Welcome to the group! Have you checked out the Wyze thermostat compatibility survey? I don’t believe your contacts will transfer over, so you may have to take a look and see what you can make of it.
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Welcome to the Wyze community @Senthil!
I have seen other users who had this proprietary labeling method with the A, B, C, and D wires. The system wires may be compatible, but they may not show up in the compatibility checker because of this labeling methods. I’d suggest that you have a professional take a look at your system before making any decisions on buying or not.
I’m also going to tag in @Chuan for their opinion on this one!
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Thank you @Brlepage for helping.
@Senthil, Brlepage is correct. A, B, C, and D are not standard wiring so you will need to figure out how do they translate to standard wire names. It could be common R, W, G, Y but we won’t be able to confirm remotely. One way to try is the wire color, R=red, W =white, G = Green, Y = yellow, however, we strongly suggest to use an HVAC tech to trace the wires for the best result.
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@Senthil
I would try looking in your furnace if you feel up to it, see if you can find those wires coming in and see how the board is labeled where they connect to it. If you have a plug that connects to the board with those 4-wires in one plug it is probably proprietary. If, like mine they go down and connect to the board individually the board was marked with what each wire meant (for example R, W, G, Y, C)
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Ok Thanks for the info. I will check my furnace board wiring.
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Thanks for responding. I am going to check my furnace board wiring and will see if they match color and if naming is just different.
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Those thermostats are communicating using DC ± on A/B and AC± on C/D. Depending on your furnace, if the 4 wires form the thermostat go into the furnace to the IFC, the Wyze thermostat will not work. If the 4 wires go to an Equipment Interface Module outside the furnace, the Wyze thermostat will work. You will need to remove the EIM/Communicating thermostat, and extend the thermostat wire from the EIM to the furnace IFC using 5 wires (Red, Blue, Green, Yellow, White). I’m only seeing Green, Blue, White, and Red in your picture, is there a Yellow wire in the sleeve?
I checked the furnace and the 4 wires from thermostat goes inside the furnace and connects to the board and also don’t see a Yellow wire. Previously I had bought Nest and it did not work and had to return. So probably it is the same case with Wyze. Thanks Brian and to all who responded.
What is the model of your furnace if you don’t mind me asking?
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Model: Bryant plus80v
I also noticed that there is yellow wire which is connected to blue wire which goes to thermostat.
Attached the photo of wires connected outside the furnace and also inside furnace connector.
That is an 80% Furnace with a Variable Speed Blower. Without the exact model number, I can’t pull up the documentation. That being said, if it has the conventional terminals on the IFC board, the Wyze thermostat will work just fine. Downside is you will lose the Variable Speed functionality of your blower.
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I checked the manual and it shows
Model: 315AAV/JAV
Variable Speed Induced-Combustion Deluxe
4-Way Multipoise Furnace
See the attached photo. The ABCD terminals are your current thermostat wiring outlined in green. The terminals outlined in blue are for conventional wiring which the Wyze thermostat would work fine. I would have an HVAC contractor install if if you aren’t comfortable. Like I stated, you will lose the variable speed functionality on the blower.
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@Brian Thanks for the wiring diagram and explanation. I will think about loosing variable speed functionality and then make a decision. Thanks once again.
Hey Senthil I am curious if you ever came up with anything? I have the same unit and been wanting to know if I can change to Wyze thermostat? I know this post is old but maybe you see this and found something? Any help is appreciated.
Do you know what the ABCD would translate to on the board ?
What if I have a second for HVAC, how would the board know which is AC call vs heat call ?