How to set up wire to turn on just the fan

[westleycwu]

I have a heat pump and the HVAC technician mentioned that I'm missing an orange wire, so he routed the green wire to the OB slot instead.

The current wiring configuration is:

Y1 - yellow wire

W1 - white wire

C - blue wire

Rh - red wire

OB - green wire

Photo of the current wiring

Both the heating and cooling functionalities work. However, I am not able to turn on just the fan. I live in a pretty vertical townhome so the upper levels are much hotter than the lower levels. I'd like to turn on just the fan to circulate the air.

Is there a way to do that with my current wires? I'm happy to sacrifice the auxiliary heating wire. I don't live in a very cold location so the auxiliary heat is not needed.

If that still doesn't work, is there a way to configure the wires for fan/heat in the winter and fan/AC in the summer?

[zoeuvre]

Hi westleycwu, 

Thanks for posting here in the Community forum and for showing interest in our Nest Thermostats. Could you move the green wire from OB to G and see if you can control your fan after that? 

Keep us posted. We're happy to help.

Best,

Zoe