Jotul Oslo and the great learning curve

[steamtrain]

I've been reading these threads for the last few weeks and I'm amazed at the knowledge and experience of all of you fine folks! Hopefully, I can squeeze some more information out of those fine brains to either alert me to what I'm doing wrong or to set my mind at ease.

We recently purchased a Jotul Oslo for our home. The dealer/installer recommended getting the fire between 1000-1200 and then turning it down. We couldn't get it anywhere near there initially. However, since yesterday, the three fires I've started have all been burning very hot. It's the same wood we've been burning from the beginning so that hasn't changed. It seems that, even with the damper all the way down, the flames are burning very aggressively. Before, once we got the stove hot and things started dying down, we put the damper down incrementally and then coasted on coals, but now the flames aren't dying down at all. The flames actually look like they're coming from the back and riding along the top, moving forward (that might just be totally irrelevant, but I thought it was worth mentioning).

The fire is almost behaving like it does with the damper all the way open. Is this normal? Maybe we just weren't getting a great burn in there before and I'm getting better at jamming more wood in there now? It's been burning at around 500-600 for two hours now with the damper completely closed. Before that, like I said, it was running at around 1200 when it started. Pretty toasty in here.

If you tell me I'm just a champion wood burner and a bit of a worrywart, that would be o.k. too.

Thank you,
Tara

 

[remkel]

Where are you taking these temp readings? Stove top? Internal flue temps with a probe thermometer? My stove usually runs around 600 degrees. If these are stove top temps, where on the stove top is your thermometer?

Stove top temps should be between 400 and 600 degrees. I start gradually reducing my primary air around 350-400 degrees. Achieving the temps you are mentioning from a stove top measurement is going to damage your stove! Please provide us some more detailed information about where you are taking these readings.

EDIT: if these are stove top readings and your installer recommended those temps to you, I would definitely make note of that for when you have to make a warranty claim to Jotul for damaged caused by over firing your stove.

 

[BrowningBAR]

IThe dealer/installer recommended getting the fire between 1000-1200 and then turning it down. We couldn't get it anywhere near there initially. However, since yesterday, the three fires I've started have all been burning very hot. ... It's been burning at around 500-600 for two hours now with the damper completely closed. Before that, like I said, it was running at around 1200 when it started. Pretty toasty in here.

I am going to assume you miss-typed that or something.

 

[Oldhippie]

Hi Tara and welcome. I don't own an Oslo, so I'm not going to give you specific advice, and some Jotul Oslo experts will be along soon enough. It may help if you talk a little bit about the stove installation while you're waiting. For instance, what kind of house is it, single story, two story etc. What floor is the stove on. basement, first floor ..that kind of thing. Also, what wood are you burning? Dry, well seasoned wood makes a BIG difference in heat output. Have you had the wood long? Did you buy it recently, what kind of wood is it?
What damper are you adjusting, is it the stove damper or do you also have an outboard damper on the flue pipe? It almost sounds like you've got a wide open air condition there and the damper is wide open, not closed?

Pics are even better.

In general, when you start a fire you want to get the full load going strong before you turn it down and then turn it down in a couple/few increments, to get it to a nice steady state slow burn but giving you the warmth you need. The high temps you were given by the installers seem on the high side to me, but, again, I don't have that stove.

I'm sure we'll get to the bottom of this quickly.

Welcome and enjoy your new stove, they are great stoves!

 

[Shari]

No matter what your dealer told you the Oslo manual is VERY clear - stove top temps should be between 400-600. Higher than you can wreck your stove /void your warranty.

FYI: Read you manual.

 

[remkel]

Hi Tara and welcome. I don't own an Oslo, so I'm not going to give you specific advice, and some Jotul Oslo experts will be along soon enough. It may help if you talk a little bit about the stove installation while you're waiting. For instance, what kind of house is it, single story, two story etc. What floor is the stove on. basement, first floor ..that kind of thing. Also, what wood are you burning? Dry, well seasoned wood makes a BIG difference in heat output. Have you had the wood long? Did you buy it recently, what kind of wood is it?
What damper are you adjusting, is it the stove damper or do you also have an outboard damper on the flue pipe? It almost sounds like you've got a wide open air condition there and the damper is wide open, not closed?

Pics are even better.

In general, when you start a fire you want to get the full load going strong before you turn it down and then turn it down in a couple/few increments, to get it to a nice steady state slow burn but giving you the warmth you need. The high temps you were given by the installers seem on the high side to me, but, again, I don't have that stove.

I'm sure we'll get to the bottom of this quickly.

Welcome and enjoy your new stove, they are great stoves!

I think the focus right now should be getting to the bottom of the temperatures stated for running that stove, then a focus can be placed on the space heated and efficient running of the stove.

 

[DianeB]

http://www.jotul.com/FileArchive/Te...ul F 500 Oslo/Manual_F_500_USA_P17_141112.pdf

This link is to the manual. thermomter goes on the top, any corner of the stove.(page 9). Heat range is max to 600 - (page 10)

I use 2 thermometers, one for each side of the stove although mine is a Jotul Catine.

 

[webby3650]

You are gonna see 500-600 degrees, even once the air is "off". Once that thing gets rockin, it's not gonna calm down much. Never in any instance should temps be anywhere near 1200. I would be freakin out if it hit 900 on a cast stove. Did the installer tell you to do the break in fires?

 

[Oldhippie]

I think the focus right now should be getting to the bottom of the temperatures stated for running that stove, then a focus can be placed on the space heated and efficient running of the stove.

I thought that high temp recommendation was over the top, but I wasn't sure. I knew the Jotul was not a CAT stove so I figured it couldn't be a cat temp.

But regardless of what she got told, you guys can set her straight.

 

[semipro]

Tara,
You may just be a "champion wood burner". It actually sounds like your stove is working correctly but, as mentioned, getting good temp readings in the right spot is a good diagnostic. Make sure you're using an accurate thermometer too. Some are notoriously inaccurate.

The flames you see roiling over the top of from the rear to front are normal. That's the secondary burn system in action. The air control lever controls only the flow of air coming in through the little "dog house" inlet at the front bottom of the firebox. It does not control the overall amount of air that enters the stove. Once air enters the stove it can either go through the dog house to the firebox or through the secondary air tubes to the top of the firebox, or both. When you shut down the main air control your hot flue continues to create a vacuum on the stove that pulls air into the firebox. When the air control lever is closed, the path of least resistance is the secondary air tubes.

With a particularly large dry load of wood I've seen temps in our Jotul that got me worried even after closing the air control. I restricted air coming into the inlet at the bottom rear of the stove and was able to cool things down.

I personally love to see nothing but blue flames with occasional small yellow flames flaring in our Jotul's firebox. I suspect that this is when the stove is running most efficiently.

Should you have one available, an infrared thermometer is a great tool for understanding how your stove burns and what temps you should see where. I personally monitor our stove temps at the upper front left corner because its hard to see a thermometer mounted on top. At that location temps of 500-600 F seem to be normal.

There are a lot of Oslo users here so you're bound to get lots of good info.

Edit: I'd be very worried if I saw the kind of temps you mention on my Oslo, at least on an external part where I could measure. If you're measuring at the outlet I could see temps getting close to that.
You may want to read this for reference.
https://www.hearth.com/econtent/index.php/wiki/Temperature_when_metal_glows_red

 

[steamtrain]

Hi Remkel: The temperature was read from the internal flue probe thermometer. The installer put two thermometers on the stove, one as just mentioned and the other on the right hand corner of the stove. He recommended we use the probe thermometer over the one on the right hand top corner of the stove.

Oldhippie: We're burning sugar maple, ironwood, ash, and some elm. It's all been well seasoned. It's very dry and lights up easily and quickly. We live in a one story, rancher type home. The fireplace is in the basement. We're adjusting the damper on the stove. Could it be broken/stuck in the open position? Is there some way to tell?

Hi Shari: We have read your manual. I am talking about the internal flue temperature, but from these comments, it seems a lot of people use the stovetop thermometer. Maybe that's better?

Thank you, DianeB. We do have the manual. It's just that over the last two days, the fires have been behaving quite differently so we were concerned something might be going on with the stove or maybe we were just being fire burning dunces before.

Semipro: I really appreciate the explanation. I'm just about to put another load in. I'm going to watch the stovetop thermometer and see if that looks anything like the numbers you are all throwing out. I guess my concern was that there may be something going on with the flue or the stove itself as the change in how the wood was burning was very distinct from the last few weeks to yesterday, but maybe we're just getting better at loading it full?

Thank you all!!

 

[remkel]

Well, the temperatures make more sense now. Thanks for the answer.

When the stove is up to temperature and the secondaries are firing, a sustained 600 degrees stove top temperature is reasonable and actually what I expect on my stove. Seems as though you are doing just fine. Enjoy that stove, it is a great heater!

And I probably should have started with this, but welcome aboard!

 

[semipro]

I'm going to watch the stovetop thermometer and see if that looks anything like the numbers you are all throwing out. I guess my concern was that there may be something going on with the flue or the stove itself as the change in how the wood was burning was very distinct from the last few weeks to yesterday, but maybe we're just getting better at loading it full

Many things can affect burn temps including: wood quality, type, diameter, and loading characteristics; outside temps, wind speed and direction, barometric pressure changes, ash pan accumulation, ashes hiding under the ash pan, and so on.

Welcome also. There are some great folks here.

 

[Shari]

I don't think I've heard of many Oslo owners using a pipe damper to control the fire. The only control I use on my Oslo is the air control lever located center front, just above the ash lip.

The use of the air control lever is outlined in the owners manual.

 

[webby3650]

To me it makes no sense to monitor a stove from a thermometer in, or on the pipe. The installer should have put you at ease by letting you know that these temps. aren't absolute, but instead a target, as a reference. The new stoves can be very,very hot and still run a relatively low flue temp. The stove is really what needs to be monitored, the pipe temp would be simply to monitor performance and for you own reassurance.

 

[ansehnlich1]

haha, sounds like you've tapped into the "OSLO LOCOMOTIVE"

She's like a steam engine for sure, slow to get goin', but once up to speed she'll throw some serious heat

Here's what this ole boy thinks....

You've experienced a change in weather conditions, likely a high pressure system, maybe a good breeze a blowin', and under those conditions the Oslo will perform exactly as you've described, mine does all the time!

Pack 'er full, let 'er get up to speed, shut the air down, then shut it completely off, and WHAMMO, she just throws a flame in there that looks like a hollywood inferno, causing the stovetop temp to go right up to 625 degrees F and hover there for a spell, GREAT AIN'T IT

 

[Butcher]

Wow, that 1100 to 1200 deg. temp thing scared the crap outta me when I first read it. Watch yer far and as time goes on you will be able to tell how the stove is performing. You'll get alot more carefree heat outta that oslo than a stove you gotta keep fiddlin with and replacing parts.