Well, it has been almost a year since this post was talked about. With this past years very mild winter, plus the higher price of anthracite coal and the low price of natural gas, I didn't even purchase or burn one once of anthracite this season. I don't even have any anthracite coal in stock! I can't even believe that I'm saying this? I did burn 3 cords of purchaced hardwood in my new D.S.Machine stainless steel wood boiler though and it sure did the job well this past season, but not even as cheap as natural gas though, about $100.00 more. Figure?
I've been closely watching my gas bill pricing and it has maintained a steady $1.10 per therm for a year. Anthracite coal has jumped up to $250.00 per ton bulk picked up and purchased split hardwood went down a few dollars, $175-$200 per cord depending on how well seasoned it was. When I started buying anthracite in 2007, it was only $165 per ton bulk picked up, wood was the same price, and natural gas would have cost me $900-$1000 per month to heat the house to 64 degrees. This year natural gas only cost me around $265.00 per month heating the house to 72 degrees, but it was much warmer than it was in 2007.
So, I'm now pondering over making a non electric natural gas fired furnace to supplement heating the house by gravity, like a wood/coal furnace or stove does, and in the case of power outage. I like to having non electric heating stuff and thought that this maybe an intersting project. I've been slowly putting something together over the past year and a half and plan to show it when it is finished. Until then, I thought of just asking if anyone else has traveled this route or may have any ideas I may incorporate into the system?
So far it is a cast iron furnace, like a giant pot belly stove, with double lined jacket designed for gravity warm air flow, 100,000 Btu gas burners with standing pilot, modulating gas valve with a milivolt thermostat. Once I get it further along, I'll post some pictures. Until then, it will be under wrap and take a lot more time to complete. The most difficult obsticale has been with slowing down the straight through passage of the flue gases. I've been experimenting with many different internal baffle designs and just haven't come up with the best solution as of yet. Any thoughts or suggestions would be welcome. Thanks.