Wyze thermostat install with no control board on air handler

@speadie you seem to be the expert on this topic. But I am wondering if I can add a jumper from the red/ blue wire to the open blue wire that goes down to my thermostat as my common wire to run my wyze thermostat.

Something wrong with your image upload there.

  1. Is this blue wire here coming from the same bundle as the yellow, green, red, and white wires?
  2. Is there a blue wire at your thermostat?

If the answer to both questions is yes, you probably don’t need the C adapter. Instead, just strip a bit of insulation off of that blue wire and insert it into this wire nut with the small red and large blue wires that are already in there, and connect the blue wire at your thermostat to C. Make sure to tell the app that your “old thermostat” has a C wire during setup.

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Yes, the blue wire that you zoomed in on is coming from the other bundle that comes from the thermostat. I am trying to avoid using the adapter if I do not have to. It took me a minute to figure this out since it doesn’t have the control board like they show in the app.