I was wondering if anyone had come across a home heating system that uses a boiler to make hot water to supply a coil for a forced air system? I need to replace my home furnace before too long and I would also like to add an outdoor boiler. I thought maybe going to a boiler would marry well with an outdoor boiler. Other advantages I see would be boilers are generally smaller and it's easier to move hot water longer distances than air. We have a long house and are planning to add a master bedroom that would make it even longer. We currently have 2 furnaces one serving each end of the structure. I thought if I went to a boiler for the main furnace I could reduce to foot print and more easily get hot water to the addition and maybe just add blowers in 2 areas. Has anyone heard of such a hybrid system? I have been wondering about the efficiency of such a system too.