Thermostat Wiring

[facecard]

If necessary, please move to appropriate category.

I have a question about the wiring. I have a Peerless oil burner and I am going to be using Ecobee4 thermostat to control it. I haven't installed the thermostat yet.

Downstairs- RH (white) and W/B (Black) wire.

Upstairs- RC jump RH (Red). RH (Yellow). Y/O (Black). W/B (Black) wire

I am not sure what W/B wire is and what Y/O is. The instructions don't have these wires listed and the backplate doesn't have these letters on it. The existing thermostat works just fine with these wires but I am not sure the purpose of them.

Thanks.

[Dad]

Since this is not a DIY site we can't give instructions however Ecobee support can help you if you call them.