We've had a WoodChuck model 2800 furnace since about 1980.
It needed extra welding on the outside door frame when it was delivered...which the factory covered 100%.
Its been bullet proof ever since. It still has the original fire bricks on the inside.
I just saw a new one for sale at Charlies Hardware store Mosinee Wisconsin.
My father had a Yukon in the 70's, but it had been known to burn out the inside fire chamber parts. It was the "mother of all wood furnaces", but I would not own one. His was a natural gas/wood combination unit.
I am not overly impressed with the catalytic converter in the new WoodChuck furnaces. Yes, it will burn up the smoke (how much I don't know) and create extra heat from your wood, but I understand you will need a new catalytic converter ($200-300) in 3 to 4 years to maintain the original efficiency. This does not impress me.
I do agree it is well built, and what can I say? We are still using it after 30+ years! The door latch system has been improved on the new models, but I have seen better on other brands.
If only dry seasoned wood is being burned, I would consider a new EPA rated: Kuuma or PSG (AN Caddy) furnace. If you are burning a mixture of dry and non-seasoned wood, the WoodChuck will handle this chore very well.
Our WoodChuck came with 2 fans. I replaced these with a bigger single fan and a Space Guard air filter system.
About 2 years ago, I called Meyer Manufacturing and asked whether they would build an EPA rated wood furnace in the future, because I was interested in a new wood furnace.
Their answer was a big NO! Because it costs too much to get them EPA rated (other wood furnace manufacturers have paid $25,000 to have this done).
Also, their market are the bigger farm houses where burning efficiency is not as important as heating the home. Hence they are not interested in building a true EPA rated furnace.
To me, if I am going to spend $2500-$3500 on a new wood furnace, it will be an EPA unit that burns up all the smoke, and burns less wood to heat your home. The new WoodChuck's are just too "old school", and if/when the EPA clamps down on wood smoke in the future, I seriously doubt WoodChuck furnaces will still be manufactured!
They would have to be re-engineered to be more efficient, and I understand Meyer Manufacturing is not interested in spending the money to compete in this market. The catalytic converter in my opinion is a band-aid to make them more efficient. But the best efficiency is gained by re-engineering the furnace to eliminate the catalytic converter (as the competition does).
At this point, we will keep the WoodChuck until it dies, and then replace it with a Kuuma or PSG AN Caddy. The AN Caddy ($2800) has a glass front (a waste, and a reducer of efficiency) but the more expensive and smaller BTU Kuuma ($3450) has a regular solid door.
We have no smoke issues when loading wood into the WoodChuck. One has to smart about this though. If you have a big fire going...don't open the door...because it will smoke! If the fire is mostly done and I intend to reload, I crack the door open a small amount at a time, without opening the ash pan door. Then, we rarely get smoke in the house.
The smoke bypass rod is touchy on our furnace. If I let the unit get too hot with the rod pulled all the way out...it is impossible to push it back in until the unit cools down. Therefore, I religiously push it all the way in before it gets too hot (usually 10-20 minutes after starting a new fire). I only use it when loading wood into the unit...to eliminate any smoke escaping into the house.
I wish Meyer was more concerned with improving their wood furnaces to compete with the new EPA units. But with EPA regulations pending, the WoodChuck is off the list.
Best wishes.