Bosch Heat Pump is cooling when in heat mode

[wesleyjnewcomb]

I have a 3rd gen Nest Learning Thermostat. I recently had a new Bosch furnace and heat pump (BOVA20) installed. Everything seemed to be working, but today I turned on the heat, and the heat pump was cooling.

I have wires connected to Y1, G, O/B (blue wire), Rc, and W1. I do not have permissions to upload images it seems, otherwise I would send a photo. I verified in the installation instructions that the Bosch system uses the less common B wire.

I have already tried changing the heat pump orientation from B to O. That does not have an effect. And the system does not heat when in cool mode. It always cools, whether in heat or cool mode.

When I switch to the alt/aux heat source (gas), it heats just fine. It seems to be an issue interfacing with the heat pump.

[Jon67]

I have a oil heating system that is dual heat; it has both baseboards in one section of the house and Forced Air in the other. If set to Oil, the compressor of the AC would turn on even in heat mode. I did find a post that stated set the option to Gas and you will get the additional menu options. It was not the wiring but the choice you selected in the install.  It also allowed me to control turning the fan on when in heating mode.

Now I do not have a Heat Pump, but this sounds similar to what I had ran into. Rc is for cooling Rh is for heating - on many thermostats there is a jumper between these two (but I guess Nest does not use it). G is the fan, Y1 is the compressor, and the O/B should be the wire that drives if your heat pump is in Heat or Cool modes. Sounds like you already figured those things out. 

[wesleyjnewcomb · Accepted solution]

Turns out the installation wasn't done perfectly. I called the installers and a guy came out and fixed it. Not a Nest-specific issue.