I am trying to find info on some of the new variable speed furnaces and heat pumps on the market. More specifically, I am wanting to know how to connect an extra fan relay so that the blower will run on high speed instead of half speed. I install waterstoves to existing furnaces. I normally break the fan(green) wire from the thermostat through an NC terminal on a relay and power the fan with the corresponding NO terminal to prevent backfeed to the thermostat and energize "G" on the terminal strip. According to some folks I have talked to, on the new variable speed units, the "G" terminal will only bring the fan up to half speed. How can I hook up an extra relay and bring the fan up to full speed? I realize that every manufacturer will probably have a different way, but I'm hoping they will be similar.