I have an Amana Heat Pump RHA36B2A and am replacing the thermostat with a pro 1 IAQ T 905 thermostat. I have hooked up all the normal wires (Red to RH and jumper to RC, White to W and jumpered to Y, Yellow to Y, Green to G and brown to C). Then turned on the heat and it works fine. However, when I choose Cool, it stills sends out heat. I don't have anything connected to the O or B heat and cool changeover connections. Could that be my problem? If so, what do I connect to them? If not, what do I need to do to get Cool to work. It all worked fine before with my old Honeywell thermostat and I've connected all the same wires to this new digital programmable one that's supposed to automatically changeover from heat to cool. Help! Gwhatley

Yes,, you need a wire from tstat to the heatpump changeover connection to make the reversing valve switch from heat to cool