I need help hooking up my Aqua Therm wood boiler. I though it was going to work and the temp on my indoor hot water boiler went to 200 and the pressure rose to 30. I don't have a heat on it so I think I will have to do that, but, my question is: if each unit cycles their water separately, how do I keep the Aqua Therm water full? Will a heat exchanger solve my problem as to the overheating? I live in the Cedar Rapids Iowa area.