Oslo Outside Air Kit

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phatdonkey

Member
Dec 15, 2014
153
West Norriton, PA
From what I can see from instructions, it looks like an OAK for a Jotul Oslo connects to the bottom of the stove. If this is the case, will the stove still pull indoor air thru the front of the stove until the air is dialed down enough to force it thru the secondary combustion intake?

I'm considering installing one to help with drafts in the house. I can easily run the duct down thru the fireplace ash clean out to the crawlspace, then out the siding. Just curious how effective this would be due to the 2 intake points on the F500.
 
If the F500 is like the F400 I think the outside air supplies the primary air. Not sure about secondary.
 
I've got an Oslo and just gave it the once over just to be sure ... the only opening in the "shell" of the stove is the approx 2 3/4" hole on the bottom rear where the OAK would connect. It's my understanding that all air enters the stove at that location and then it gets divided up through a series of air channels to the secondary tubes at the top of the firebox and to the primary air at the front of the firebox.
 
Ok. I was going to pull the dog house out from just inside the front door to check, but I though the primary air went in right at the air control lever. I only think this because when it is wide open and pulling hard, you can hear air being sucked in there.
 
If you remove the dog house you'll see that the slider covers an opening that connects to an air channel in the bottom of the stove that is coming from that single air intake in the rear.

I would love to see a cutaway of the stove that shows the air channels - that would be so interesting! I believe that the primary air comes "directly" from the air intake and that the secondary air gets pre-heated as it runs up to the manifolds that feed the secondary tubes.

If any other Oslo owners know more about this, please chime in. I don't want to come across as the expert in Oslo airflow! :rolleyes:
 
If you remove the dog house you'll see that the slider covers an opening that connects to an air channel in the bottom of the stove that is coming from that single air intake in the rear.

I would love to see a cutaway of the stove that shows the air channels - that would be so interesting! I believe that the primary air comes "directly" from the air intake and that the secondary air gets pre-heated as it runs up to the manifolds that feed the secondary tubes.

If any other Oslo owners know more about this, please chime in. I don't want to come across as the expert in Oslo airflow! :rolleyes:

I have had it off before but didn't inspect too well. Thanks for the info. I would also like to see an exploded diagram of the stove with tube routing. That would be very cool.

Thanks for the info.
 
I have had it off before but didn't inspect too well. Thanks for the info. I would also like to see an exploded diagram of the stove with tube routing. That would be very cool.

Thanks for the info.

You bet! I'll be looking forward to hearing how the OAK works out for you if you decide to go with it.
 
Thanks for the input guys. A test confirms all air comes thru the rear inlet. I had the Mrs. watch as I covered the hole with a gloved hand and with the air all the way open it was starved for air when covered.

I will be ordering the kit in the next few days and install in mid January after a vacation.
 
Thanks for the input guys. A test confirms all air comes thru the rear inlet. I had the Mrs. watch as I covered the hole with a gloved hand and with the air all the way open it was starved for air when covered.

I will be ordering the kit in the next few days and install in mid January after a vacation.

Cool! Great test!
 
I've got an Oslo and just gave it the once over just to be sure ... the only opening in the "shell" of the stove is the approx 2 3/4" hole on the bottom rear where the OAK would connect. It's my understanding that all air enters the stove at that location and then it gets divided up through a series of air channels to the secondary tubes at the top of the firebox and to the primary air at the front of the firebox.
That makes sense. With our Castine I could tame a raging fire by covering the OAK hole, but I sold the stove and never explored the secondary feed.
 
It seems like two or three times a year I have to partially cover that hole . . . usually with a sheet of folded up tin foil . . . to slow down a burn. It's always interesting to see the effect of partially closing this hole as the secondaries go all "slow-mo" and I've seen purple flames on a few occasions.
 
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If all of the air is supplied through the bottom hole, then why would an outside air kit be of any benefit?
Think about it, if you have to choose between the far colder outside air being supplied to the stove, or room temperature air, would it not make
more sense to continue using the house as the return air plenum? The last time I checked, it requires fewer BTUs to heat up 70 degree air then to
heat up 20 or 30 degree supply air.
 
If all of the air is supplied through the bottom hole, then why would an outside air kit be of any benefit?
Think about it, if you have to choose between the far colder outside air being supplied to the stove, or room temperature air, would it not makemore sense to continue using the house as the return air plenum? The last time I checked, it requires fewer BTUs to heat up 70 degree air then to heat up 20 or 30 degree supply air.
The bottom hole is where the outside air connects. Connecting an outside air supply stops the stove from pulling room air which is replaced by air pulled from leaks in the house. Or, in some cases the house is either too well sealed to supply the combustion air via leaks or the stove is in a negative pressure zone and the stove performs poorly. Thus the outside air supply.
 
I also don't think when you're talking about a 1200 degree firebox, a 50 degree differential won't matter at all. Also, the reason I'm looking into it is to lessen the draftiness of my 65 year old home. Its worth the 45 bucks for me to do it to see if there is a difference.
 
More efficient to run 50 degree cooler air straight into the combustion than to draw it through every room in the house, across the floor and into the stove..
 
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Yes, if your stove is direct connect, you can block the intake to snuff the fire in a pickle.