Sunday, September 21, 2008

Dave- Battleship!

More big plans ahead for SW or should I replace big with "HEAVY"... About a month and a half ago, we were searching through Craigslist and came across someone selling un-used 8" insulated chimney pipe, the exterior stainless steel variety. Knowing that our eventual plan was to put an additional heat source in the basement of SW, we jumped on the deal. So then the search was on for "what" we would put in the basement. After weighing all the options, it seemed like the best possible solution for us was some kind of forced hot air furnace that was wood fired. Reasoning was as follows

Requirements/Challenges:

o Camp isn't always occupied in winter, so draining a hydronic system was not ideal, radiant floor isn't really an option either due to risk of freezing as well as cost.
o No pellet stoves, yes they are easier to vent but require constant electrical power and the fuel is very specific.
o No fossil fuels
o Keep the cost down.

Solution:

o Forced hot air... minimal or no electricity required and the possible replacement of motors with DC
o Wood fired. Lowest tech and most readily available fuel.

We looked at some of the new units and found them to be VERY expensive 5K+ as well as the most common type being simply a relatively small add-on wood furnace made to augment existing gas systems.

Craigslist and some internet scrounging comes through again.



This unit was barely used, in super shape and was MASSIVE. Once we contacted the seller, we discovered that it had another huge and unexpected advantage.... There is a coil attached to the firebox which will heat water. The firebox is the "black section" and is surrounded by the orange outer case which is hollow and allows for air to circulate around the entire furnace.

I don't have any specs yet on the approx BTU output of this unit but its firebox is the size of a dump truck and I doubt they come any bigger. Seller was GREAT and helped me dismantle all parts and get it moved out of his basement and onto our small flat bed trailer, no small feat!


Given the intended location of the furnace at SW, pretty sure we can run the small amount of duct work required to heat both the bathroom and the spare bedroom on the first floor. We may even be able to use some flexible duct to run behind the (future) cabinets in the Kitchen. Going to start some research on a gravity/thermal hot water setup for a storage tank. The limited reading so far seems to show that with proper safety precautions we could put in a hot water storage tank nearby and allow the thermal properties of the heated water to circulate through that tank without the use of an electrical circulator pump. We will put a bypass and circulator pump on it anyway, so its available should electricity be plentiful OR have the option of running without. The research will also include replacement of the blower fan as well as any duct fans with DC units.

SO, basically couldn't be happier with the find. The addition of this furnace to SW should allow us to really get the camp up to a comfortable temperature quicker, provide heat in areas we don't currently have it, as well as regulate the heat during the evening. One thing we've learned with the large wood stove is that it does struggle to get the large mass of the camp up to temp (when arriving) but once there you really have to keep it burning hot to maintain the temp downstairs. While doing that the unintended consequence is that the loft is about 150 degrees.

There may be some slightly greener options (radiant floor or a wood burning gasification type furnace which may be more efficient) however... Given the off grid nature of our Cabin, the cost and complexity of those options and our desire to not use any fossil fuel, this was the best we could come up with. I guess we were able to stay somewhat green by finding the perfect unit used, vs. having to buy one new.

Next big challenge, other than moving this battleship into its permanent home will be to get a 12" hole in the concrete foundation wall for the chimney pipe. THAT should be fun!

*publisher's note (Lisa) I am so not making the whole in the almighty foundation. That is going to be all on D :)

1 comment:

The Scavenger said...

Great find guys, gotta love craigslist for all those good deals. I'm sure this furnace will be great for SW. Good luck and I can't wait to see more of the progress.

Chris