Originally Posted by Bob Miller
But I don't equate tossing a 40 year old furnace
to thoughtless waste any more than tossing a 7 year old tire, even if it does still hold air. It's like playing the lottery, I just don't like the odds that older LP devices come included with.
What are the odds? Tell me Bob, If there are no rust perforations, or any significant rust at all, and the unit is a sealed, welded construction, what do you think are the risks? As a direct vent appliance, I think it is much safer then even the catalytic heaters, which your reply did not address. Do you think they are safe to use? What about wood stoves in a house?
As a function of the construction, these furnaces run at a slight vacuum. The operation can be compared to a wood stove. Many wood stoves don't have a positive seal at all, but, due to the flue, they operate at a significantly higher vacuum. The point is, even if they do have a leak, they will likely not emit much CO. Though if I had one that leaked, I would dispose of it as well, after I removed the gas valve for reuse.
Clearly you don't agree, but to me, getting maximum, safe, value out out of something is good. I understand the principle of operation, and I know there is nothing wrong with the heat exchanger, (very through inspection, and paint
job on the parts that don't get very hot). Since this was original equipment, it doesn't make any noise, and it operates with no electrical
power, I can't see any reason to throw it away. If you had offered your appliances, (fridge, stove, and furnace
?) for sale
, I am sure there would have been people very interested in buying them. The gas valve in the furnace
costs $250, or more to replace. The fridge
, if it works, would also be appreciated by someone. If it doesn't work, then parts of it can be used. I am currently looking for an original two burner stove. So yeah, waste is accurate.
I will follow this post with one titled "The pros, and cons, of gravity heating", (sung to the tune of "The pros and cons of hitchhiking" by Roger Waters)
I would really love it if you could chime in on specific concerns you have about the use of a 40 year old furnace. Hopefully more then "who knows what could go wrong?" You see, with such a simple appliance, there are really only a limited number of issues it can have. The gas valve is one I have dealt with, but corrosion issues with the fire box, or exhaust vent, I have not seen.
Please take a look at the threads linked to below. I completely disassembled the furnace from my first Trillium
4500. The parts I ended up painting
were the burner, below the stainless steel plate that has the gas vents, and the fresh air intake, (not in any pictures). They were the only parts that seemed to be rusting. The rest of the fire box is galvanized steel. At first I thought it was aluminum, since I could not see any rust. Once I disassembled the furnace, I found some actual rust, associated with the studs on the door mostly. The studs tend to sheer off due to rust, but can be replaced. Stainless sheet metal screws work too.
The telescoping exhaust / intake vent was really difficult to get to telescope. It had fused, due to rust. I eventually got the folks at Trillium
/ Outback to work on it. They had to remove the intake duct, that surrounds the exhaust. This allowed them to get a propane
torch on the exhaust, so they could heat it to red hot and then, using a pipe wrench on the two telescoping sections, they were able to get them apart. The pipes involved are made of heavy gauge steel. Once apart it was clear that while the rust had fused them together, there was still lots of steel left. The fact that the pipe wrench did not damage them illustrates my point.
So, the fire box is intact, the exhaust vent is solid, The gaskets on the door have been replaced, what else could be wrong? Actually, the gas valve had to be replaced. This was quite expensive. I would have really liked to have a source for a used part, but most people just throw them away. BTW, I am offering $50 to anyone who wants to sell me their gas valve from an old Duo Therm furnace.
Some Background info:
How to physically remove a heater ...
Your Wagonmaster heater may kill you