Homemade OAK... whaddya think about this idea?

[EarlyMan]

Hi Gang -

I had a MT Vernon insert installed back in May. Like others, I was told by my dealer that OAKs were a waste of money. After reading comments from all you wise pellet stove owners, I tend to side with you that they keep your home warmer. I think I would like to make my own OAK and was wondering what you folks think about this plan.

My insert is located in an enclosed inside pocket wall. (There was originally a propane fireplace in its place). The pocket is a triangular shaped wall enclosure, not open to any other area in the house. My thought was to install a dryer vent outside the house, use flexible dryer vent hose (aluminum) and run it through the floor, into the pocket where the insert is installed. It would not physically attach to the stove; rather it would supply cold air (along with some heated inside air) into the pocket, which would then be sucked into the MT Vernon. I have read that some OAKs have a hole cut in them to allow some inside air to mix with the cold air; this is what I'm thinking my setup would mimic.

Please give me any and all advise and opinions on this this hair-brained Summer project!

EarlyMan

 

[Delta-T]

i would just attach directly to the stove. if you don't you are likely to have cold air migrating into places you don't want cold air to migrate to.

 

[EarlyMan]

i would just attach directly to the stove. if you don't you are likely to have cold air migrating into places you don't want cold air to migrate to.

Hi-
In order to attach it directly to the stove, I'm pretty sure I would need to purchase the "official" Quad OAK - which is what I was trying to avoid. Also, I read that some OAKs have a hole cut in them to allow the cold air to mix with room air (to prevent frost, I think). Wouldn't this arrangement also allow cold air to migrate into other areas? Just axein'... I don't know myself, that's why I'm here.

EarlyMan

 

[Delta-T]

I'm not sure what quad uses for their "kit" but if you have an intake flange then a pipe clamp on the flex will usually do the trick. the stoves I have seen that do not bring 100% outside air by design are the only ones I've seen that mix the intake and room air. by default, if a unit uses any inside air for either combustion or airwash it becomes moot to make it a true "outside air" system. If the kit is just an adapter to allow you something to clamp the flex to, then its a good idea, just running a flex line from the outside without connecting to the unit doesn't mean the stove "will" draw air from there. I'd view it as an open hole in your house. Stoves that do the "either/or" probably only have the outside air option to get them to qualify for mobile home installation, not for any real efficiency gain.

 

[heat seeker]

IMO, what you propose would just be another hole in the house. A true OAK will result in the combustion air totally separate from the house air, a "sealed" system in which only outside air enters the combustion area, and the exhaust goes outside. That eliminates the stove causing drafts in the house, and combustion problems caused by wind or exhaust fans in the house. (A dryer, for instance, exhausts a lot of air to the outside, and would compete with the stove for air.

It is possible to create negative pressure in the house, which could conceivably draw the stove's exhaust back through the intake (without an OAK) and into the house. Obviously, that is undesirable.

A friend of mine learned a lesson about negative pressure in the house the hard way - turned on his attic fan with no windows open, and the chimney damper open. The ashes in the fireplace "exploded" out into the house and covered everything.

In short, I strongly recommend that you connect directly to the stove.

 

[hossthehermit]

OAK, SCHMOAK. Did it work without one? Does the manufacturer require one?

 

[Don2222]

Hi Gang -

I had a MT Vernon insert installed back in May. Like others, I was told by my dealer that OAKs were a waste of money. After reading comments from all you wise pellet stove owners, I tend to side with you that they keep your home warmer. I think I would like to make my own OAK and was wondering what you folks think about this plan.

My insert is located in an enclosed inside pocket wall. (There was originally a propane fireplace in its place). The pocket is a triangular shaped wall enclosure, not open to any other area in the house. My thought was to install a dryer vent outside the house, use flexible dryer vent hose (aluminum) and run it through the floor, into the pocket where the insert is installed. It would not physically attach to the stove; rather it would supply cold air (along with some heated inside air) into the pocket, which would then be sucked into the MT Vernon. I have read that some OAKs have a hole cut in them to allow some inside air to mix with the cold air; this is what I'm thinking my setup would mimic.

Please give me any and all advise and opinions on this this hair-brained Summer project!

EarlyMan

That is a great idea ! In fact my old oil boiler in the corner of the basement could not have an OAK kit because they did not make one. So I built a room around it and put a dryer vent in without the flapper to feed fresh air into the room. It works great!
My new oil boiler has an OAK kit.

Also my old apartment building in Malden Ma had a boiler for 44 apartments in a room with a closed door in the basement. It was a huge oil boiler and would starve without outside air. It did have a window that had to be left open all winter or the boiler would not run right. That was the 1st OAK I ever saw!! So they have been around for a long time!!

So just take out the flapper because it works the opposite way. In fact you can buy a flapper for the inside of the dryer vent to keep warm air from escaping the house. That is what I did.

So good luck and go to it and don't worry about any slack, it will work fine!

Just make sure the air will go into the stove. Not sure if you have to remove a knockout.
See MT Vernon OAK pic below:

 

[Snowy Rivers]

Its amazing how much WIND can come through a dryer vent pipe.

Bloody hurricane can whistle through one of those hoses.

I agree with the idea of connecting it to the stove.

My large WHIT has a OAK pipe on the rear that's about 1-1/2 inches in diameter, but inside therear of the stove it is just open for a few inches and the actual air inlet to the fire pot is farther in.

The cold air can get into the rear of the stove but is sort of corraled there.

Every manuf is different though.

Good luck on the OAK

Snowy