RCMJR & misoilman, tnx for your replies. RCMJR: LDJ appears to have been in business since 1999. According to the LDJ website they claim the boiler is "Great for radiant floor heat systems". I'd be interested in talking to existing users to see how they are getting on with the the system. I took a closer look at their page about the corn boiler and they claim it's thermostat controlled, perhaps it's able to be dialed down. The picture of it looks like a water heater with a hopper sitting next to it. I'll post the url for the corn boiler. The capacity of the water heater portion is eighteen gallons. They also have an option that would allow the boiler to provide hot water for "domestic" use. So would be able to heat water for shower's, washing dishes etc. Right now the utility room has two gas fired water heaters sitting in it, one for the floor heat and one for domestic use, I think. We'd have to talk the heating and plumbing guy that took over from the H&P guy that had been maintaining the system for many years. The retired fellow is still in town and we might be able to talk him into coming over and orienting us with the systems. misoilman: Having the seller comfirm the moisture content of the corn would be the first thing I would insist on when purchasing the corn. I do know from talking with the folks at the elevator, they will not accept corn that is more than 15 percent moisture. I also need to check with the city to make sure there isn't an ordinance that would preclude me from having a small gravity box sitting next to the carport. If the gravity box is small enough, I'd even consider backing it into the carport. Alas, there is no basement on this dream house. Just a thick concrete slab...:-) So We'll probably use a couple of five gallon buckets for transfer of fuel from the box to the hopper. I'd just consider it a form of exercise...:) We're also a bit concerned about the age of the plumbing in the floor as it is original to the house. The impression I got from the house inspector was that the in floor plumbing was put in place then had the concrete poured over it. I'm going to have to have someone that has better eyes than me and know's what they're looking for, look at the blueprints and see if we can find out how thick the concrete is. Luckily, we've secured a "home warranty" from the seller for at least the first year (at their expense), and there is a possibility of extending it through the second year. I should also probably state that the corn boiler is not a done deal as we are still in the early part of the research stage. Although, a friend of ours has suggested we check the website of the Governor of Illinois and see if there are any grants or other incentives that we might be elgible for. Governor Blagojevich (Bla-goy-a-vich, what a mouthful) is very interested in promoting alternative fuels and energy use in Illinois. Here is a link that might be useful: LDJ's Corn Boiler page

Stick with the steam that is the most confort as far as its not dry heat like a forced hot air. Why anyone would go to forced out air is just taking the cheap way out. A hot coil in an air handler will work better. Also have e you thought of radiant floor system at all or off the return of your boiler you can have a circulaing pump and add baseboard to the new room. if 75 gallon water heater isn't cutting it you may want to try a tankless water heater. Don't go with forced hot air you wont be happy. Here would be my options that you can run by a good plumber. 1 tankless water heater to do radiant floor or coil on a air handler, with a heat exchanger you can also do domestic water and never worry about hot water. the neg side about this is tankles has to be on a maintnace program for scalling and general PM. 2 put a B&G pump on the return of your steamn boiler and use that hot water to do a basboard or new radiaters in your new addition. for your a/c I would go witgh a ductless systeem if its only one big room. here are the three manufactures I would go with 1. tankless I would go with takagi ( make sure its sized correctly) 2. air handler I would go with first company. 3. fujutsi if you where using a ductless. If it was my house I would use high baseboard and heat it only to 140 degrees stick that on a tankless water heater and get my domestic hot water thrue that also. or radiant floor instead of baseboard. Use the fujitsu unit for the a/c of the house.

Conditions: 1. 3 zone hydronic floor heating, 3 zone pumps, 1 primary pump. Lochinvar Knight 155 mod-con. Basement slab, 1st floor and 2nd floor (extruded plates, insulated). Oversized boiler because of drive-under garage that might get additional modine heater. And global cooling on the way... 2. 3 zone forced air heat and cool. Trane XV95 (2 stage), 3.5 ton AC, ultra-aire dehu. No controls installed yet. House is very well insulated. Leaning towards Honeywell Tru Zone. No idea if such a thing exists, but here it goes: 1. Centralized (if possible) - 1 nice display panel, with multiple sensors for multiple zones. 2. Operating both forced air and hydronic. And dehu/circ. Trane furnace has variable speed fan and electronic cleaner that can circulate at very low speed, all the time. 3. Wifi enabled so it can be tinkered with from sofa or 2,000 miles away. 4. Forced air would be used between April and October (cooling June-Aug) and radiant November-March. Although recirc through forced air would be nice year round. So forced air mainly for cooling and late Spring/early Fall supplemental heat and possibly emergency heat if boiler fails. 5. Would love good reporting feature, like Ecobee. Above alone might give me a negative answer on 1 centralized unit controlling everything. If that's the case, and I have to use separate controls for hydronic and forced air, I would like to see my options too. I know I can make it happen with hydronic on it's own and forced air alone, but i bet there are some new fancy products I am not aware about plus I would still like to control air quality (humidity/circ when hydronic runs on it's own and when we use just the wood burning stove)

Air-to-water heat pump systems are relatively new and were only made practical by newer high-efficiency inverter-controlled variable-speed compressors. I looked into this a good bit before finally opting for geothermal. These air-to-water systems work better in dry climates than in relatively humid ones where they tend to ice up in winter and have to go through periodic defrost cycles, which detract significantly from the efficiency. So if you're looking into performance specs, you have to make sure that is taken into account. As noted, Daikin Altherma makes some very nice systems, but they are not cheap. If I remember correctly, they were going to be $8-10K just for the hardware, not including installation and not including the radiant piping itself.