air intake placement

[morpho]

Hey folks,
So, I have been trying to figure out a logical place to put a passive air intake to make sure the stove has enough air.

The cabin is sealed pretty tight.

Not sure where to put a vent.

here is a rough layout of the place.

Thoughts?

 

[morpho]

Ack!
That image is huge...sorry.

 

[morpho]

as a side note I can use a bit of fresh/stale air exchange in this place...so not sure if close to or far from the stove makes more sense.

 

[begreen]

Use the thumbnail option when posting a picture for a smaller version that can be clicked on to see the full sized one.

I would hook up the stove's outside air kit (OAK) connection to the adjacent exterior wall if concerned about the house being too tight.

 

[morpho]

Hey begreen,
Thanks for the resize and tip.

So do the actual outside air hook-up huh?

I vaguely remember reading somewhere that "the engineers" are now saying don't do those as they make no real difference anyway.

Maybe I will just open a window!

 

[begreen]

Who are the 'engineers'? There are some installations that will only work well with an OAK.

 

[morpho]

hahaha...you know..."them"
I just read it somewhere....

I guess my main concern is that if I put the intake across the room I am going to be feeling all that cold air running past my feet...making me feel cold. Which kinda makes the wood stove pointless.
If I put the air intake really close to the stove I won't get much fresh air exchange into the house. (which is good and bad depending on how you look at it)

 

[TimfromMA]

OAK stands for outside air kit. It pulls air in from outside.

 

[morpho]

Hi Tim,
thanks.
Not sure if this is the way to go or not though.
Would love the simplicity of just hooking up directly to the outside, but would also like a bit of air exchange in the house.
Also wonder if the direct hook-up would create draft problems due to introducing -40 air directly into the stove?

 

[TimfromMA]

If your house is pretty airtight, this may be your only option. You really don't want negative pressure inside the house.

 

[morpho]

Yes the airtightness has it's benefits and its drawbacks. I did a really good job when I built it so she is really tight...snare drum tight actually.
Maybe I will get the specs from Morsø for the kit and pop a vent in behind the stove and if I decide to do a direct hook-up that will make it easy.
so...behind the stove it is.

 

[morpho]

hmmm...I was just in the utility room and was pondering all things utility ...as you sometimes do in that room... and maybe I will put one in there as well. The refrigerators rear is exposed through the wall (did this to keep good airflow around it so the heat can dissipate easily) maybe I will make a simple vent box behind the fridge and bring the incoming cold air past the rear of the fridge. Hill billy heat exchanger!

 

[TimfromMA]

hmmm...I was just in the utility room and was pondering all things utility ...as you sometimes do in that room... and maybe I will put one in there as well. The refrigerators rear is exposed through the wall (did this to keep good airflow around it so the heat can dissipate easily) maybe I will make a simple vent box behind the fridge and bring the incoming cold air past the rear of the fridge. Hill billy heat exchanger!

Jeff Foxworthy would be proud.

 

[morpho]

Begreen
I found "them"

Excerpt:
According to John Gulland of the Wood Heat Association:

“The supposed benefits of outdoor air are not supported by research. Laboratory and field reports have revealed that providing outdoor air is not a simple or effective cure for spillage, and that some designs could create a fire hazard.”

 

[Mt Bob]

You may want to consider an hrv and a oak,they seem to have good success in alaska.

 

[morpho]

Hey Bob,
Funny you mention that.

I have an issue with HRV's ....mainly that I have no forced air to hook it up to and limited power to run it, no where to run ducting, and they are all made for MASSIVE houses...well massive compared to mine anyway. Not to say I don't want one...but just not practical or feasible.

I came across this:

The European perspective
Is it all much ado about nothing? That’s the impression Jesse Thompson got after speaking with representatives of (broken link removed to http://www.jotul.com/en-us/wwwjotulus/), a Scandinavian stove manufacturer.

“They say very clearly that in Scandinavia, houses with HRVs [heat-recovery ventilators] and balanced ventilation don't use outside air intakes, that it's a ‘strange Canadian thing’ that causes more problems than it fixes,” Thompson says. “They mentioned the same issue as Martin: backdrafting into your fresh-air intake is disastrous and a real fire hazard.

“The idea is that if you have a balanced ventilation system, your house will be at the same internal pressure as the outside, and you won't get the strong pressure differentials that can create back-drafting. As well, they quoted very low cfm needs for the combustion in modern EPA stoves, I remember 15 cfm? In any case, it's much lower than a big tube through your wall would be providing and doesn't need additional supply beyond normal house leaks.”

 

[Mt Bob]

Hey Bob,
Funny you mention that.

I have an issue with HRV's ....mainly that I have no forced air to hook it up to and limited power to run it, no where to run ducting, and they are all made for MASSIVE houses...well massive compared to mine anyway. Not to say I don't want one...but just not practical or feasible.

I came across this:

The European perspective
Is it all much ado about nothing? That’s the impression Jesse Thompson got after speaking with representatives of (broken link removed to http://www.jotul.com/en-us/wwwjotulus/), a Scandinavian stove manufacturer.

“They say very clearly that in Scandinavia, houses with HRVs [heat-recovery ventilators] and balanced ventilation don't use outside air intakes, that it's a ‘strange Canadian thing’ that causes more problems than it fixes,” Thompson says. “They mentioned the same issue as Martin: backdrafting into your fresh-air intake is disastrous and a real fire hazard.

“The idea is that if you have a balanced ventilation system, your house will be at the same internal pressure as the outside, and you won't get the strong pressure differentials that can create back-drafting. As well, they quoted very low cfm needs for the combustion in modern EPA stoves, I remember 15 cfm? In any case, it's much lower than a big tube through your wall would be providing and doesn't need additional supply beyond normal house leaks.”

I have not researched them much,as my cabin will never be air tight,but was thinking of one of the small outside wall mount ones,seems they have had good success except xtended -30 weather.They are more to change the air in a tight room/house/workplace so it does not become a "sick house"

 

[morpho]

Its the power use that kills it for me.
I run completely off solar, which works great until you want to add fancy doodads that run inefficient fans and high resistant heaters to warm air and or defrost plate exchangers etc.
Like I said...I want one...but just not enough to bring the devil poles (power poles) onto my property.
Now you have me googling wall mount HRV...damn you Bob...damn you!

 

[Mt Bob]

Glad to be of ASSistance

 

[morpho]

ok...I need to go and do some splitting before I end up spending the day in front of this stupid screen...again.

 

[morpho]

Jeff Foxworthy would be proud.

Oh I put that guy to shame. I probably put his second cousin from down in the "holler" to shame.

 

[firefirefire]

When I worked on the retail side we used to sell these kits and people seemed like them. You can install it where ever you want. They have a damper inside so you can stop the outside air flow if you would like. (broken link removed to http://www.condar.com/asv_homegarden.html)

Here is the manual for the 6100 series outside air kit. Pretty simple installation, though it appears that of you are going to use the direct O/A kit, the hole comes I to the bottom of the stove. May affect your hearth.

https://drive.google.com/file/d/0B-D5WwKM3Di7cDhVVWVGSXlnZEU/edit?usp=sharing

Hope this helps!

 

[begreen]

hahaha...you know..."them"
I just read it somewhere....

I guess my main concern is that if I put the intake across the room I am going to be feeling all that cold air running past my feet...making me feel cold. Which kinda makes the wood stove pointless.
If I put the air intake really close to the stove I won't get much fresh air exchange into the house. (which is good and bad depending on how you look at it)

These are quite separate issues. The stove oak should be relatively close to the stove, within 10-12', to avoid friction losses in the intake pipe.

Air exchange in the house is a 24/7, 365 day concern in a really tight house. The ideal solution would be an HRV that warms incoming fresh air using the heat in the outgoing stale air.

 

[morpho]

firefirefire,
thanks for the link.
Any sense how those ASV's would handle really cold temps? Frost? Condensation etc.?

I have a louvered vent cover on my range fan that looks similar and she freezes up solid. I have to go outside with a 12 foot pole and whack at it until the flaps free themselves.
(probably going to take it off and replace it with a simple vent cover and use one of these instead:
(broken link removed to http://tamtech.com/store/one-way-air-flow-valve-6-duct-bath-fan-range-hood-exhaust-dampers-indoor-air-quality,Product.asp)

Thanks for the OAK instal sheet as well!

begreen,
Ya the HRV would be ideal, but just not in my situation. WAY too much power consumption.
Maybe I will make my own except with small super efficient DC computer fans and no heater. I have looked inside one before and they are nothing but a box with crossed layers of coroplast...not exactly rocket science. Ya, I'll do that right after I finish the 80 other projects on the go!

 

[begreen]

A good HRV/ERV design is a bit more complex. I would think that an HRV made with just coroplast would be relatively inefficient. There are better heat transfer media. I think FanTech uses and aluminum core. Are you off grid and thus worried about power consumption? Some, like Fantech's use a low power muffin fan I believe.

Here's a good thread on home-made HRVs.
http://ecorenovator.org/forum/conservation/891-diy-ventilation-heat-exchanger-6.html

This is a better topic for the DIY forum.