Jotul Oslo V3

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Robert Watson

New Member
Aug 18, 2023
23
Albuquerque, New Mexico
Mod Edit: Move to its own thread to make this discussion easier to discover in the future.

Hi All!

I'm in the market for a new wood stove and have contacted a few dealers to price out options. For reference, my house is about 2000 square feet, and the existing fireplace is on the first floor on an interior wall with an open floor plan. We have zoned heating so in my ideal scenario, we would set the upstairs thermostat to a normal temp, and the downstairs thermostat to 50 degrees or so, and light up the wood stove for extra heat when we spend time down there. It also needs to be a reliable backup for power outages (so no reliance on blowers or fans).

The dealers I contacted offered me the following 3 options:

1) Jotul F 500 V3 Oslo CF
2) Vermont Castings Encore
3) Lopi Evergreen Next-gen Fyre insert (this would be installed top vented but without the surround or fan system). The dealer said this model is preferable to the cat model for simpler operation and install.

The prices are all within an acceptable range for me so it's not a factor in the decision. I've read some terrible things about the VC Encore, but it seems like the Jotul isn't much better. Which leaves me to believe the Evergreen might be the best choice. However, I'm hoping someone here can explain the differences in user experience so I know what I'm getting myself into.

Thanks in advance for your help!
I just bought a Jotul F500 V3 (catalytic) and did a detailed comparison of features (see attached spreadsheet) comparing a Regency 3500 to a Lopi Endeavor. The Jotul ticked all our requirements. It's a beautiful stove, and is ranked #3 out of 174 EPA certified wood stoves for the lowest pollution rate (0.5 gm/hour). I gave it a total score of 36, versus only 15-19 for the other stoves on the spreadsheet.
 

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I just bought a Jotul F500 V3 (catalytic) and did a detailed comparison of features (see attached spreadsheet) comparing a Regency 3500 to a Lopi Endeavor. The Jotul ticked all our requirements. It's a beautiful stove, and is ranked #3 out of 174 EPA certified wood stoves for the lowest pollution rate (0.5 gm/hour). I gave it a total score of 36, versus only 15-19 for the other stoves on the spreadsheet.
It also has the most complaints from users out of those 3
 
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People have complained about a warped grate on the bottom of the stove, but this is due to overfireing (by leaving the ash pan door open when starting a fire). Jotul says that this a prohibited operation because of the plate warping problem.
 
I'm curious...what kind of problems have people said about the Jotul stove?

It doesn't have a bypass/damper plate to move. We had problems with our Vermont Castings bypass plate warping (likely due to overfiring).
 
I'm curious...what kind of problems have people said about the Jotul stove?

It doesn't have a bypass/damper plate to move. We had problems with our Vermont Castings bypass plate warping (likely due to overfiring).
Premature cat failure due to the lack of bypass also needing to clean the clogged cat multiple times a year again due to the lack of bypass.
 
Thanks !

I don't' mind vacuuming the cat a few times a year. It's easy to reach from the front. But, why would a bypass reduce the clogging effect?
Because the ash is sucked through the cat every time you load the stove or empty ashes etc. With a bypass it doesn’t. There is a reason every other stove with a cat in it has a bypass. Some people are reporting having to physically poke through the cells to clear them
 
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That makes sense. Thank You.

I was thinking if people start a fire with the ash pan drawer open (and with ashes in the bottom), then air rushing up from the bottom will cause loose fly ash to rise and clog the Cat on the way out. But, again, Jotul doesn't recommend doing that (as tempting it might be to do).
 
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That makes sense. Thank You.

I was thinking if people start a fire with the ash pan drawer open (and with ashes in the bottom), then air rushing up from the bottom will cause loose fly ash to rise and clog the Cat on the way out. But, again, Jotul doesn't recommend doing that (as tempting it might be to do).
Yes using the ashpan will destroy the stove that is nothing new to the v3. Many people just let the ash pan fill up to avoid leaks.
 
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We have a few in the field. After a few decades of Jotul being our #1 seller, he have backed off almost completely. The Oslo has been a real deal killer… I’m trying to find a real fix for it, but it’s elusive. The Ashpan doesn’t always seal up tight, even though it’s latached. Overfire is a common issue.
 
Thanks, Webby3650. That's all very interesting. The ash pan door on our new Jotul is difficult to close , I suspect because the gasket is relatively thick when new. So, it should be sealed up pretty tight (when new). For older stoves, when the gasket gets compressed, I could imagine that air could leak in through the air pan, causing the problems that people mention with warped bottom grates and fly ash clogging of the Cat.

There's another factor to consider is that fire wood in the Eastern US has a much greater moisture content than in the West (I'm in New Mexico and our seasoned wood is 3-6 % moisture). Does burning greener wood cause lower stove temperatures and problems with the Catalytic Combustor getting clogged more ?
 
Your dry Wood will burn faster and hotter. That’s not helping you. Get a couple bright flashlights and put in the the ash pan area (remove the pan) turn out the lights and look for leaks. Open and close the door as if you are in a hurry. Any light escaping?

A damper might make sense.

Time will tell how it will work for you. How tall is your chimney?

Be careful with dry wood. I had a big piece of really sappy pine. Was saving for a cold night. It sat by the stove for a week drying. Once I loaded it up it was off to the races. Stove top temps were 800 in the middle. I think parts were glowing inside.
 
Excellent suggestions! I will do the flashlight test before we light the first fire.

Our stovepipe is about 18 ft tall (it's a 2-story living room).

That's interesting about sappy pine. We have mostly pinyon pine and scrub oak in New Mexico.

IMG_0764.jpeg
 
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Because the ash is sucked through the cat every time you load the stove or empty ashes etc. With a bypass it doesn’t. There is a reason every other stove with a cat in it has a bypass. Some people are reporting having to physically poke through the cells to clear them
Yes, clogging of the CAT may be a worse problem for the Jotul F500 because the CAT is always "ON". But it is the lowest polluting stove especially for the FIRST 1 HOUR, according to EPA test data (because there's no bypass). Here's a research paper showing that the particulate emissions rate is very high for the first 30 min. for a non-catalytic stove (see Figure 3) and quickly drops down to a low, steady rate after the stove has come to temperature.
 

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  • A Study of Wood Stove Particulate Emissions.pdf
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Yes, clogging of the CAT may be a worse problem for the Jotul F500 because the CAT is always "ON". But it is the lowest polluting stove especially for the FIRST 1 HOUR, according to EPA test data (because there's no bypass). Here's a research paper showing that the particulate emissions rate is very high for the first 30 min. for a non-catalytic stove (see Figure 3) and quickly drops down to a low, steady rate after the stove has come to temperature.
Ok but clean in the first hour doesn't matter if it doesn't work. Or when people get frustrated and just start running them with no cat. I really hope it works out well for you but i have my doubts from what I have seen
 
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The plugging of the cat also refutes the marketing claim of the large cat "eliminating "back-puffing” and draft sensitivity that is common with traditional catalytic stoves."
That said, with an attentive operator that maintains the cat well, the stove may work fine, especially if the wood burned generates little ash.
 
The study you provided is from 1979. It really has no bearing at all on any modern stove cat or noncat.
Good point. I'll look for more recent papers.

I think this transient phenomenon is strongly related to the surface area of the wood being burned. During start-up, the total surface area burning is HIGH (because of small pieces of kindling). The larger surface area emits a greater number of particulates during start-up than a 1-3 logs of oak that have a SMALL surface area. The temperature of the stove is irrelevant for this start-up effect, in my opinion, because all wood burns at a similar temperature, whether it is a big piece or a small piece. Does that make sense?
 
Good point. I'll look for more recent papers.

I think this transient phenomenon is strongly related to the surface area of the wood being burned. During start-up, the total surface area burning is HIGH (because of small pieces of kindling). The larger surface area emits a greater number of particulates during start-up than a 1-3 logs of oak that have a SMALL surface area. The temperature of the stove is irrelevant for this start-up effect, in my opinion, because all wood burns at a similar temperature, whether it is a big piece or a small piece. Does that make sense?
No because the more surface area you have burning the faster the stove gets up to the temps needed for secondary combustion in either cat or noncat. So maybe more particulate at start but it drops faster the sooner you get up to operating temp
 
I get it. The stove in the 1979 paper probably did not have secondary combustion. Good point.

I talked just now to an EPA testing/certification company and they agreed that the fuels that have large surface areas (e.g., kindling) have greater particle emission rates. This argues to minimize the amount of paper to use on start up, because a sheet of paper has a very high surface area per unit weight. OF course, you can't get around using small-sized kindling to start. Lots of paper probably contributes to clogging of the Jotul CAT.
 
I get it. The stove in the 1979 paper probably did not have secondary combustion. Good point.

I talked just now to an EPA testing/certification company and they agreed that the fuels that have large surface areas (e.g., kindling) have greater particle emission rates. This argues to minimize the amount of paper to use on start up, because a sheet of paper has a very high surface area per unit weight. OF course, you can't get around using small-sized kindling to start. Lots of paper probably contributes to clogging of the Jotul CAT.
The lack of a bypass is the problem. Again there is a reason every other stove with a cat uses a bypass. I can pretty much guarantee most of them will be running with no cat after about 5 years.

BTW I almost never use paper to start a fire and really only start at most a dozen fires a year. The rest is just a reload on coals
 
The lack of a bypass is the problem. Again there is a reason every other stove with a cat uses a bypass. I can pretty much guarantee most of them will be running with no cat after about 5 years.

BTW I almost never use paper to start a fire and really only start at most a dozen fires a year. The rest is just a reload on coals
Thank you, Mr. Holler. You're a wealth of good information.! I appreciate your candor.

With the Jotul, you can see the CAT glowing red when it's fully working. We'll monitor that (I bought an Infrared Thermometer gun), and as soon as the CAT temperature drops by 100-200 F, we'll do some cleaning of the CAT. Plus, we're going to stop using paper. And, we'll start doing top-down fires. (We may get one of those propane blowtorches to start the fire). I may need to learn how to remove the top plate, so that we can take the CAT out and clean it. We live in a passive solar, super-insulated house in New Mexico (with lots of sunshine), so we only build fires about once a week.
 
There are two small (1/4") holes on both sides of the ash pan box that you can block with small magnets. Many people have reported longer burn times using this approach. Or, keep the ash pan full of ash, which does the same thing.
 
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