I am new to the wood furnace market and am trying to educate myself to my options before I make any decisions but here is my deal: I am buying a new house that is a 3400 sq foot colonial with 3 floors of heated areas. The house is currently heated by a hot air oil furnace with 3 zones and heats the DW with an indirect water heater tied in. I have been looking into the Napolean HMF 200, Kumma 100 and the PSG Max Caddy . I'm not positive if I want to add-on the existing furnace or just do a full replacement. Can any of the aforementioned furnaces handle 3 different zones or are they just designed to heat one zone? What would you guys do?