flue for Jotul F3

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Heat Sink

New Member
Aug 5, 2021
3
Long Island
I'm purchasing a used Jotul F3 (the newer model with the 2 air controls) for a new installation. Stove is configured for a top vent, and will go straight up through ceiling, a few feet of attic space, and then above the roof. We'll have single-wall pipe up to the ceiling, with a ceiling support and adaptor to class-A insulated pipe from there on up.

As we plan the work to be done, I have a question about "future-proofing" this install, specifically, how advisable it would be to install an 8" stack from the ceiling pass-through and upwards, using a reducing adapter to fit the 6" single-wall pipe coming from the stove.

My reasons for asking about this are twofold:
* Potential for replacing stove in future with a larger output model that would perform best with, or require, an 8" flue
* Past experience with a VC Encore that drafted poorly and back-puffed with a 6" flue

Now, I have family with an older F3 (where the air adjustment is on the ash lip, no secondary air control), with a 6" flue in a rear vent, and they have zero issues with poor draft, so I'm not worried about the draft for this particular installation if I had 6" flue all the way up.

But I am concerned that using a 6" to 8" stack might introduce it's own set of issues. So, I'd welcome any thoughts or advice about how best to approach this!
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,681
South Puget Sound, WA
The majority of modern stoves use a 6" flue, even stoves 3 times the size of the F3. There is nothing likely to be gained by going to 8". The backpuffing with the Encore if it was a neverburn model is not uncommon. As long as the flue system height is at least 15' tall, backpuffing when burning dry wood should not be a problem.
 
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Heat Sink

New Member
Aug 5, 2021
3
Long Island
Hey, thanks.... great to hear about the utility of 6" flue.

As it turns out the Jotul is a no-go - checked it out today and declined to purchase. Clear signs of abuse and neglect.
* missing knob on front door lever
*starting air adjustment lever snapped off
* significant interior rust
* lots of exterior paint chips and on inner door lip
* rusted and loose bolts at the top of the air plates
* and so on

As plan B, we are also considering two new models from Hearthstone at a local seller:

Manchester
Green Mountain 80

The GM80 has an 8" flue, so would it be fair to expect that we would need an 8" flue all the way up? If so, that's my vote for the Manchester (which already had it based on looks).
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,681
South Puget Sound, WA
If buying new it might be worth looking a bit more and considering other options like the Jotul F55.
 
Nov 21, 2020
152
NeK Vermont
Hey, thanks.... great to hear about the utility of 6" flue.

As it turns out the Jotul is a no-go - checked it out today and declined to purchase. Clear signs of abuse and neglect.
* missing knob on front door lever
*starting air adjustment lever snapped off
* significant interior rust
* lots of exterior paint chips and on inner door lip
* rusted and loose bolts at the top of the air plates
* and so on

As plan B, we are also considering two new models from Hearthstone at a local seller:

Manchester
Green Mountain 80

The GM80 has an 8" flue, so would it be fair to expect that we would need an 8" flue all the way up? If so, that's my vote for the Manchester (which already had it based on looks).

What state are you in? Are you sure your talking about an F3? When you say the stater air lever on the ash lip is broke and there is no other air control, it sounds like the f-400. The air on the f3 is the spot above the door, and the spot right on the door and I havnt had either of those been broken on any ive done.
If your in the nothereast, there are a few good people out there that do really amazing work turning what looks like a crappy jotul right back to brand new again.
 

Heat Sink

New Member
Aug 5, 2021
3
Long Island
I'm in NY- just updated my location.

You're absolutely right, I assumed that my family member's stove was an F3 because the styling was so similar. They in fact have the F 400, and nothing is broken on their stove, thankfully! And now that I've seen the F3 in person, it's definitely a smaller than ideal stove for our space.

As luck would have it, my local dealer still had the Manchester, and so we pulled the trigger. Hopefully we'll have a better experience with this, than with the Encore in days past! Not to knock the Encore too much - it put out a great deal of heat and was efficient - but there was an underlying finicky nature with regards to the catalyst and the tendency to back-puff.
 
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