System Application Standard Efficient Gas Forced Air, High Efficacy Gas Forced Air, Oil Forced Air, Electric Forced Air, Hot Fan Coil, Geothermal Heat Pump, Air to Air Heat Pump, Hot Water Radiant Heat, Steam Stages Heat Cool Up to Heat Pump or Conventional Power Method Battery.

System Application Gas Electric or Oil Heat Pump Stages Heat Cool Power Method Hardwired or Battery Terminal Designations Rh, Rc, C, Y, W, G, B, O Description 4.