Fresh air intake for wood insert is it worth the Effort?

[chipster314]

Busy getting my fieplace ready for the insert. Block off plate, Hi temp wire to run power in from below, and possibly fresh air intake.

I have an older house so it is not exactly air tight.

So is it worth the while to try and get a fresh air intake hooked up into the opening. Not sure if there is a certain code that must be followed or material that must be used.

 

[LLigetfa]

If you don't provide dedicated outside air, the air will come from cracks and crevices with a noticable draft. Reduce the consumption of air and it reduces the cold drafts.

If you have a very leaky house and you plug up all the cold drafts but don't plug up where warm air is escaping, you will have a pressure deficit that can cause smoking issues and problems starting a draft in a cold chimney.

 

[Dune]

Definitely worth it. Otherwise you are using already heated air for combustion, then sending it out the chimney.

 

[burntime]

I use indoor air on my insert. The only thing I notice is when it is cold, say less then 10 degrees, you need to damper it down slightly or there is a net heat loss. At that point draft is so good due to the differential in temps that you do not need to start it wide open anyway. I heat my home down to -30, thats as cold as it got so far...

 

[RedRanger]

Not worth it in my opinion.. But then I live in a relatively mild climate, and our large insert is located in a small room. And even with that "evil exterior chimney" we still get cooked out of that space and have to migrate to the upstairs living area unless we want to start opening windows in the rec-room.

Maybe consider trying it without? Can always add it later if needed..

Unless Code dictates you must have it.??

 

[chipster314]

Well after posting I went back at it. I was able to get 4" flex vent down clean out hole( had to ovalize it). and attached 4" fresh intake vent in clean out hole minus the weather guarding so it sits flat on bottom of fireplace. Packed around the vent with Roxul.

Running it into crawl space for now, will get it to outside wall when I can

 

[Hogwildz]

Don't have one here, never been an issue.
If you want it, I say go for it. This is one of many debated subjects on the site.
As far as all that air being sucked into cracks etc. My stove takes in very little air, matter of fact its mostly always all the way to low.
Not much air needed, not much air taken from the house. Yes some, but nothing to cause a draft.
As far as the theory your sending heated air in and up, same can be said for the extra effort for stove to heat that cold air being taken in from outside, either way, IMO its a wash either way.
Heated air being used and sent out, or wasted energy to heat the colder incoming air.
For me, no, its not worth it. Don't need it here. For you, thats up to you.

 

[LLigetfa]

Definitely worth it. Otherwise you are using already heated air for combustion, then sending it out the chimney.

Six of one, half dozen of the other. Outside air is heated inside the stove which takes that same amount of heat that would otherwise enter the room.

The only real difference without is that the cold makeup air passes through the living space where it may be noticed as a cold draft. If you have an OAK and don't use the stove much, there can be a small constant amount of cold air entering the stove, stealing heat from the room, and then going up the chimney.

 

[Hogwildz]

Definitely worth it. Otherwise you are using already heated air for combustion, then sending it out the chimney.

Six of one, half dozen of the other. Outside air is heated inside the stove which takes that same amount of heat that would otherwise enter the room.

The only real difference without is that the cold makeup air passes through the living space where it may be noticed as a cold draft. If you have an OAK and don't use the stove much, there can be a small constant amount of cold air entering the stove, stealing heat from the room, and then going up the chimney.

Although not sure how common, There have been instances reported about where the OAK is installed and having problems pressure wise due to a prevailing wind in certain directions.
As you said 6 and 6. Either way, heating with wood is time well spent.

 

[tkrock]

Well after posting I went back at it. I was able to get 4" flex vent down clean out hole( had to ovalize it). and attached 4" fresh intake vent in clean out hole minus the weather guarding so it sits flat on bottom of fireplace. Packed around the vent with Roxul.

Running it into crawl space for now, will get it to outside wall when I can

You'll be glad you did it. I know you'll never know what the difference is... but imagine standing next to it with your front side warm from the fire and your backside cold because of the draft. That would stink right? Well doing what you just did pretty much eliminates that feeling!! And of course it is more efficient that way. Good luck, wise choice!

 

[RedRanger]

Well after posting I went back at it. I was able to get 4" flex vent down clean out hole( had to ovalize it). and attached 4" fresh intake vent in clean out hole minus the weather guarding so it sits flat on bottom of fireplace. Packed around the vent with Roxul.

Running it into crawl space for now, will get it to outside wall when I can

You'll be glad you did it. I know you'll never know what the difference is... but imagine standing next to it with your front side warm from the fire and your backside cold because of the draft. That would stink right? Well doing what you just did pretty much eliminates that feeling!! And of course it is more efficient that way. Good luck, wise choice!

You had to say that didn`t you?--lol

Actually without the OAK we do have cooler air rushing towards the insert (at floor level) and the warmer air being pushed higher and out of the room because of that. A natural convection current. Which in our case serves us well because we want that warmer air pushed up and out of the rec-room and migrating upstairs.

Sorry, but just had to be contrary, because in our circumstance it just makes sense. Whatever works best for each individual household would be the correct course of install.

As long as it meets "code"..

 

[Hogwildz]

Guys,
seriously, how much cfm of air do you think is being taken into the stove?
Now in a smaller super tight, or tight mobile home with gas water heater, drier, stove etc, yes def need an OAK due to it and other appliances competing for tight air space.
Other than that, if you are feeling a draft from you EPA stove taking indoor intake air, you have more problems than the need for an OAK.

 

[North of 60]

Two reasons why I believe an OAK is necessary for my climate.
1) Its nice to know where the cold air is entering your house other than to discover it was getting in a place where it can freeze a pipe and cause a flood or frost up the windows and doors so bad it makes it difficult to open them.
2) If you are humidifying your house with a electric humidifier to compensate for that cold dry extreme weather than an OAK is a no-brain-er. Why send it up your chimney or have it add extra frost around those areas that are leaking air into your house for your stove.
My 2 northern cents. N of 60

 

[RedRanger]

Guys,
seriously, how much cfm of air do you think is being taken into the stove?
Now in a smaller super tight, or tight mobile home with gas water heater, drier, stove etc, yes def need an OAK due to it and other appliances competing for tight air space.
Other than that, if you are feeling a draft from you EPA stove taking indoor intake air, you have more problems than the need for an OAK.

Didn`t say that we were feeling a draft. No, no, just saying that when siting on the reclining couch watching the big screen, that if you bend over and place your hand on the floor, you can feel the cooler air migrating towards the stove, all the while the too warm air being blasted out of the insert is damn near driving us out of the room.

And the thermomoter and the humidifier don`t lie. Try 80F+ and 30 humidity? With the portable humidifier I manage to keep it at 40+. Lots of heat without the OAK, more than enough. Hot,hot, hot, nough said from this contrary geezer. :coolgrin:

 

[LLigetfa]

Guys,
seriously, how much cfm of air do you think is being taken into the stove?

Good question. When I am outside near my OAK inlet, I clear the snow away from it and out of curiosity, I always unglove my hand and hold it in front of the intake. It is a significant amount.

My EPA stove has a notched butterfly so that it's impossible to completely shut off the air. If I'm away from the house in really cold weather and not burning in the stove, frost will form on the glass door and the metal above the door where the air wash system is.

 

[chipster314]

Here is a pics of what I did

 

[chipster314]

close up

 

[chipster314]

Temporarily run into crawl

 

[Hogwildz]

Not sure what insert or stove your installing, but you might want to check stove & manual for an actual hook up on lower back for the OAK to connect directly to.
YOur just asking for a serious cold draft with it installed that way.

 

[chipster314]

Yes I am going to have to go down and check out the unit(Osburn 2200) to see where the intake actualy is. I figuerd I would put this in while doing the electrical and if It cannot be used just cover over it with a plate or Roxul. How would one put in a Fresh air Intake? Is OAK short for this?

 

[North of 60]

Temporarily run into crawl

If your crawl is vented than your done. Its better than outside if you cannot do a direct connect as Hogz has stated.
P>S> your certainly making a valiant effort. Block off plate and all. Good on ya.

 

[chipster314]

Nope crawl all sealed up. Going to have to pop a hole in the old vents that I sealed closed and covered over. When I bought the house it had the floor insulated and nothing on the walls with wall vents. Heating and cooling and inspection guys told me this was backwards. Allowing to much moisture into house and cold air though vents. My crawl is basically part of my living space( even though I cannot hang out in there LOL/has cement floor) so out came the floor insulation and up went the water proofing R25 Insulation then vapour barrier. Huge difference. Now that area is warm and so is the floor above it and no moisture issues. When I cut through the insulation to get to clean out, could you ever feel the cold from the foundation.

 

[North of 60]

OK then, back to the direct connect.

 

[Hogwildz]

Yes I am going to have to go down and check out the unit(Osburn 2200) to see where the intake actualy is. I figuerd I would put this in while doing the electrical and if It cannot be used just cover over it with a plate or Roxul. How would one put in a Fresh air Intake? Is OAK short for this?

Outside air kit is fresh air intake from outside the living space, correct.

 

[rustynut]

hi there,
this is my second stove
first was a basement install cat stove
lots of chimney and draft problems
frequently had smoke in the house - enough to trigger the smoke alarms
that long chimney, while boxed in , was hard to warm up
now this latest is a non cat short straight vertical with outside air
on vacation thru the holidays and have only had it in for a week so i'm watching it pretty close
we had 40 - 50 mph winds two times in the last week and had absolutly no ill affects
i'm thinking that the outside air allows for a much better balanced system while not pulling
the cold air in every available opening in this drafty place
very pleased with my decision to go with the outside air
best of luck
rustynut