Thanks for the response! Extremely helpful. I would like to get rid of the cat. I am going to send you a private message.
Hi,
I hope you don't mind but I am also going to post my response to your message here on the forum. The reason is: I think it is possible that someday someone could have some use for this information (I know that I have benefited many times from old answers to old questions). Also, maybe I am wrong about something, or there is a better/different answer. It's always good to see if others may have a different opinion then I have- maybe you'll get additional information.....
When a catalyst is working perfectly it's pretty impressive. Unburnt gasses light up in it, it glows red, you get some extra heat and the exhaust in the chimney is pretty clean. As a result, you get a little more heat out of your wood and the chimney stays cleaner. But.... that is under ideal conditions. A cat's performance diminishes over time and they need to be replaced at least every 5 years. Also, they clog very quickly and have to be kept cleaned out (I heard that in the back vented position they are even more prone to clogging). You also really have to know what you are doing to make a cat run well. You have to first get a hot fire burning, then close the bypass. Then you have to open the bypass before you open the door to put in more wood. Repeat..repeat repeat. Another bad thing is that the bypass is mechanical and is subject to wearing out and having problems. On top of that, unless the cat is really functioning well (i.e. clean and relatively new) the stove really does not breath as well as if it weren't there (even with the bypass open). I think newer models with cat's are probably a lot better, but unfortunately we have first generation designs that were rushed into production and were somewhat crudely implemented.
I have 27 years experience using the cat, I literally only have 3 days experience without it, so I can't give you a full report on how it is working, but so far it is great and I wished I had done it long ago. I removed the cat, I also replaced my 8" chimney with 6" chimney, 7" single wall stove pipe with 6" double wall and changed the stove's 7" flue collar to a 6". So my improved chimney system may also be providing some of the benefits I am seeing. The stove is just so much easier to operate now. You really don't have to watch it or play with any controls. I just open the door, throw wood in. You start it up with the damper control open, after the fire starts going I turn it all the way down and it still burns pretty energetically. It is providing plenty of heat (yes, I heat my home with it) and what is coming out of the chimney doesn't look too bad. The thing that I REALLY love about the cat's absence is all of the extra volume I have recovered inside the stove. I can now really fit a lot more wood and bigger logs then before. It seems cavernous now. As far as negative's- I have seen few yet. I guess the biggest one is that I can't operate the stove at a really low smolder. That means you have to feed it a bit more wood. As a result, overnight burns are a little shorter, not as many active embers in the morning, but still acceptable (again, only 3 days to evaluate). It will be interesting to see if the chimney requires more frequent cleaning.
As for your technical questions. Did you see my other recent postings? There are some photos and info in these that may help you better understand this. Yes, you use the exact same flue collar whether it is mounted on the top or back. Just move it. The back burner plate can be found if you search for it online as Jotul part number 101935. I bought mine at Woodman's parts plus. The top baffle is part number 101941 and I got mine at Stoveworld. These were new part's that came from Jotul- they are still making them for other countries, but these stores are selling them for the old pre-cat model 8 here in the USA. You do not want to leave that catalyst assembly in the stove. Either completely fix it and put in a new catalyst, or take it out. I have tried running the stove with a dead cat with the bypass in an open position and it really does not work well. The stove ran well with a good cat used properly and it now runs well in a non-cat configuration- but not in the middle. When you remove the cat assembly you will just have a simple flue collar to mount on the back- that is it. The stove will be empty- and you will be looking straight out of a hole in the back. You need to take out your old back burner plate and replace it with the new 101935 part. That will block your view of the back opening. Then you will put the new top baffle 101941 on top of this plate. The two parts work together to form a channel to direct the exhaust up then back down and out the back of your stove
Do NOT run your stove without putting these new parts in! You will have fire going straight out your flue. It would be both dangerous and you would be throwing away heat. Those two new parts are not a modern secondary burn system, but they make the stove run much more efficiently than without them. Please look at those other posts I just made and you will see some photo's to help you. Here I will post a photo of these three parts: the flue collar (you can use your old one, just be careful when removing it as the old bolts may be seized up and break off in it ), the old back burn plate with the new one, and the new top baffle. The only challenge I had was getting that top baffle to fit in snugly- one of my other posts will show you how to do that.
