Wire my thermostat and with out a control board

@speadie
This looks normal to me - but when I hooked up my new Wyze (I did connect blue to black and green to green at the Unit)…I seemed to call for both heat and cool at the same time…during the test phase. I put everything back and put the old thermostat back in and everything seems to be working normally. Thoughts?


When you connected it to the wyze thermostat, what wires did you tell it your old thermostat had? Generally the only way I would expect it to be running ac and heat at the same time is if you had told it you had an o/b wire- or perhaps the green wire is somehow triggering the heat to come on. What model of heater is this?

Sorry for the delay - busy with family in town. I don’t have any idea why it would call for both either… I’m a bit hesitant to connect it up again. I told the Wyze Thermostat that I had Red, Yellow, White, Green and Blue. It’s a Coleman Model EB15A.
Attached is the Schematic. I’m also confused by the Green wire, why is it not connected now? Should I connect it or not?

From the schematic, it looks like when either Y or W is called it starts the fan, so the G wire isn’t needed. Maybe there’s a bad coil on the fan that is allowing Y and G signals to cross. try connecting it to just Y, C, R, and W and see if the problem re-occurs.

Thanks. I will try late today to see what happens.

Installed without the Green wire, seems to be working. Looking at the schematic, it doesn’t look like adding the green wire should cause any issues. But I’ll leave as is since it’s working.
Thanks!

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