I have an American Standard dual fuel system. Heat pump on stage 1 and 2. It uses two compressors in the outside unit. Smaller compressor for stage 1. Bigger compressor for stage 2. Natural gas as a backup for stage 3 or emergency heat.
I currently use a nest learning thermostat. It works fine. The Wyze fails on stage 2 heat and cool. The nest uses y1 for stage 1, y2 for stage 2, o/b for reversing valve, w1 for stage 1 heat.
I am almost convinced the issue is in the test routine of the wyze. I did not leave it on the wall long enough to play with it when it failed the test.
Could be a nice thermostat. But needs a few changes for the multiple hookup differences in reading all the post on the forums. I’m not sure wyze is big enough to tackle all of these new items that seem to be buggy at the same time.