6" or 8" chimney for the Equinox

[mowmow]

Hi Everyone,

I am installing an Equinox wood stove in my 3500 sq ft home and am wondering if I should go with the recommended 8" chimney or reduce to 6". I know this may sound like a stupid question (manual says don't do this), but here are my reasons for asking:

1) Configuration: The stove is located centrally to the two-story house (which is fairly heat-efficient) and will be rear-vented for about 2 feet with double wall pipe (the reduction from 8" to 6" would take place immediately on the back of the stove, using a double wall reducer) through an interior wall into a clean-out tee and then straight up 25 feet through the interior of the house using Simpson triple-wall stainless steel chimney - enclosed the whole way up. Intake air will be fed via the intake kit from the well-vented crawl space. This seems to be a fairly ideal chimney configuration and should produce a strong, consistent draft.

2) The dealer is telling me that they are selling fewer of these than he expected due to the fact that it is just too big - people are baking themselves out of their home, and the unit cannot be throttled back without sooting up the chimney. He was going to buy one himself but has downsized for this reason.

3) I am looking for burn time with this stove rather than peak output. I am doing everything I can to get good circulation in the house, but am concerned that higher burn rates will be uncomfortably hot locally.

4) As I understand it, throttling back too far is often a cause of sooting due to slow velocity and cooling in the chimney. A smaller diameter would seem to counteract this.

5) It seems that 8" diameter is specified for this stove to allow reliable operation over a BROAD RANGE of venting arrangements, most of which would be less ideal than my situation. Thus, my installation and use pattern may be on the end of the range that least requires the 8" vent size.


So here are my questions:

* There are cases where a chimney can be too big in diameter. Could this be the case for 6" and my installation?

* What are the real dangers of running with a 6" chimney in this case? Is there a fire hazard, or just the possibility of puffing or smoke spill as I add wood?

* The last six feet of the chimney will pass through a 24"x36" 2x4 framed and sided (but currently not insulated) enclosure. Should I wrap the triple-wall chimney pipe with insulation to reduce condensation? What insulation should I use for this?

* Does anyone have experience with the Equinox that might relate to my concerns?

* How does a damper fit in with this - should I include one?


I can accommodate either the 6" or the 8" size mechanically, and just want to get the best overall performance at lower burn rates, without sacrificing safety of course.

Thanks for your time!
mowmow

 

[yanksforever]

To be safe... it manufacturer says don't do it... then don't do it!

 

[Todd]

I've been waiting for someone to try this with the Equinox. I've heard of some people getting away with a 6" for the big Blaze King. When I measured the Equinox fire box it wasn't the 4cu ft they state, I think I got 3.1 and there are many other stoves in that range that exhaust with a 6". With your taller chimney I think it might work fine. Is it legal, I don't know and I doubt a local inspector would sign off on it and your insurance may have something to say as well.

 

[mowmow]

Yanks: Is it safer to soot up the chimney?

 

[Dakotas Dad]

Since you don't have the stove, all your questions, and most if not all the answers you get, are based on a theoretical problem..

Here is what I would do.. call the manufacturer, explain your problem/question, see what they say.


EDIT: BTW, if I was all worried about building to small of fires in a large stove all the time, I would just get a smaller stove. You don't need an Equinox to get over night burns.

 

[begreen]

This is a hypothetical thread, as we don't have a boatload of experience here and you haven't tried this either. I follow your thinking and it might work out fine. Hard to say without trying it. You'll be the guinea pig. The dangers would probably be smoke spill and balky operation in milder weather. Is there a reason why it can't be hooked up with a straight up interior flue instead of rear exit to the tee? That would seem to improve the chance of success.

As for the upper part of the chase, do not have the insulation in contact with the pipe. The manufacturer is very clear that this is a not to be done. Insulate the chase, not the pipe.

For the last question, I see no need for a damper. Retrofit it if need be, but I doubt it will be necessary.

 

[mowmow]

Thanks for the advice and insight guys.

I talked to the manufacturer, and they said though it would probably burn fine with 6" in my case, it would still do better with 8. They also said that it should slow burn with 8 just fine as well, as long as the intake is opened up a bit for a while after adding fuel. They also said that the unit was tested early on with 6" and did not pass EPA.

So I will let someone else be the guinea pig on this one. Going with 8.

Cheers!

mowmow

 

[Todd]

That's interesting that they said it may work fine in your situation. I bet because you have a taller 25' chimney and it didn't pass the EPA test with a 6" because they use a shorter 15' chimney in that test.

 

[mowmow]

Yep - agreed. Frankly, my bigger concern is the LEGAL stuff - insurance, etc. Bummer is I already have the 6" - guess I can use a good chunk of that in the barn soon though.

mowmow

 

[Gridlock]

I think that is a good decision. Check the following thread: https://www.hearth.com/econtent/index.php/forums/viewthread/60261/

 

[mowmow]

Thanks for the link Gridlock - a little warm/fuzzy for the WAY MORE EXPENSIVE 8" setup!

 

[Wood Heat Stoves]

i have had several customers run the equinox with 6" flue(against my advice) and it has been ok for all of them