Bryant Geothermal Heat Pumps GCUp to 37 EERUp to 5.2 COP GZUp to 30.5 EERUp to 5.1 COP GPUp to 30 EERUp to 4.6 COP GBUp to 28.1 EERUp to 5.2 COP GWUp to 25.7 EERUp to 3.8 COP