Now that copper has gone from $4.00/lb to $1.40/lb how long does it take for prices to work through the system. I just bought approx. 100' of old finned copper at the scrap yard for $25 and plan to assemble a water to air HX. I have most of the fittings I need as leftovers, could I expect to puchase lower cost fittings in 3 months, 6 months..........? Have any of you seen or heard of ecovair NG powered heat pumps? I think they use an internal combustion NG engine and can utilize the waste heat. I think they are just beginning to import and the smallest units are 8 ton capacity. Also, what is a baffled geothermal system?