Outside air

[Robert Tee]

Purchasing my first pellet stove. Have received conflicting advice on whether to arrange outside air intake for combustion vs allowing the stove to draw room air into combustion chamber. How important would this be in a typical residential installation? (Stoves considering are Harman XXV and Quadrafire Mt. Vernon AE)
Thank you.

 

[womaus]

Purchasing my first pellet stove. Have received conflicting advice on whether to arrange outside air intake for combustion vs allowing the stove to draw room air into combustion chamber. How important would this be in a typical residential installation? (Stoves considering are Harman XXV and Quadrafire Mt. Vernon AE)
Thank you.

I'll be watching this thread closely. When I was looking at buying a new stove the majority of the dealers recommended against OAK, looking at the manufacturers installation instructions (Ravelli, Harman) they all show it as the preferred method.

I live in a 1920's house, it's a bit drafty due to it'a age. Fresh air transfer / stale air is not a problem. I'll be installing outside air due to the fact that I can't see exhausting the already conditioned warmed air from inside the house.

Looking forward to see what the experts recommend.

 

[TimfromMA]

A pellet stove draws air in through the air intake, through the combustion chamber and then right out the vent. Imagine having a fan in your window blowing your heated home air right outside. This is precisely what a stove without OAK does. This air has to be replaced from somewhere and will get drawn in from all over the place creating drafts. Installing OAK will allow your stove to pull in combustion air directly from outside.

 

[johneh]

I installed an OAK even though the dealer suggested against it .
I just could not see heating the air to only draw it outside
throw the stove
In other words why pay to heat the outside
It cost enough to heat the inside !

 

[jackman]

Same here, I put in the OAK even though the installers said it was not needed. It's more efficient with an OAK.

 

[womaus]

Same here, I put in the OAK even though the installers said it was not needed. It's more efficient with an OAK.

Are there any dealers or pro installers that habit these forums? Can they cut in with reasons why most stove dealers advise against?

 

[NYBurner]

The OAK is really meant to alleviate drawing excessive vacuum in a tight house, so depending on where the stove is located and the character of airflow in the house will dictate if it is 'needed'. As others have said, not having one is literally making the house pull in outside air to make up the difference so I think it is a good idea. They are cheap and can be run in during install for next to nothing.

 

[jackman]

Are there any dealers or pro installers that habit these forums? Can they cut in with reasons why most stove dealers advise against?

I'm no dealer but the impression I got from my installers is that it was a way to do less and finish early. The installation cost was the same with or without.

 

[Tonyray]

A pellet stove draws air in through the air intake, through the combustion chamber and then right out the vent. Imagine having a fan in your window blowing your heated home air right outside. This is precisely what a stove without OAK does. This air has to be replaced from somewhere and will get drawn in from all over the place creating drafts. Installing OAK will allow your stove to pull in combustion air directly from outside.

Best Explanation of an OAK ever..
should be a Sticky

 

[funflyer]

A pellet stove draws air in through the air intake, through the combustion chamber and then right out the vent. Imagine having a fan in your window blowing your heated home air right outside. This is precisely what a stove without OAK does. This air has to be replaced from somewhere and will get drawn in from all over the place creating drafts. Installing OAK will allow your stove to pull in combustion air directly from outside.

Exactly right, and I have tested this myself. Why some dealers say it's not needed is beyond me. I can only guess that on some installs the OAK can be a PiTA so they don't want their installers spending more time than absolutely necessary on the job to keep more $$$ in their pockets.

 

[Wilbur Feral]

See Tim's excellent answer.

See Jackman's response on the reason dealers don't like to install OAKS. Well, that and the fact that most have no training in building science, and most states require little in the way of licensing to own a stove shop. There are excellent dealers and installers (kap is certainly among them) but so, so many never think past whether the stove will burn properly with or without an OAK. It usually will, using your already heated and humidified, very expensive air vs. cold, dry and free air from outside.

 

[rona]

Exactly right, and I have tested this myself. Why some dealers say it's not needed is beyond me. I can only guess that on some installs the OAK can be a PiTA so they don't want their installers spending more time than absolutely necessary on the job to keep more $$$ in their pockets.

The subject has been beat to death every year and from a dealers viewpoint the potential customer comes in looking to save some money by buying a stove so they figure out a price and the customer comments , Oh I didn't think it was going to cost that much. This before he gets the exh pipe and install bill. When he adds those up he is having second thoughts then are you going to suggest a second hole in the wall and more pipe cost? The dealer may loose the sale as his competitor down the road will say , Oh you don't need to put that in as the stove will run just fine without it.
My told me I didn't need the outside air either and I noticed little drafts that we didn't have previous to the corn stove so I added another hole and that eliminated the drafts.
In a extreme case I helped my dealer do a install at a nightclub with bar, grill, rest rooms all having exh fans. When the exh fans ran the flame just about ran out as the stove couldn't get enough air so we had to add a second hole for outside air and the stove ran perfect.

 

[TimfromMA]

If you do install an OAK, make sure you insulate it. The pipe itself can get quite cold as it pulls in cold outside air. Before I insulated my OAK pipe, I would literally have a puddle on the floor underneath due to condensation.

 

[bogieb]

Yeah, what everyone above said. My P61a was installed by the dealer, who didn't install an OAK. I am not one of those customers that even blinked an eye at the cost I was quoted for each thing so don't know why they never even mentioned it as a possibility even the the manual says "highly recommended". My house is not tight (and was even less so when the stove was installed) and I got a lot of wind currents when the stove ran. I installed an OAK a month or two later and it made a world of difference. When I got my main floor stove, although I had to have an OAK for clearance issues, I would have done it anyway to keep from having those cold drafts.

Bottom line is you may not need an OAK if yo udon't live in a mobile home or need it for exhaust clearance issues, but it makes life more comfortable in a lot of instances (I won't claim all instances because there are some here that don't have one and don't seem to have issues).

 

[Ambient]

I had plumbed an insulated OAK with the original install. I had thought of modifying it to help move air within the house, by putting it through an interior wall. The adjacent room needed to be warmed up, so I could use the "OAK" to draw air form that room and the supply would be the common doorway which would allow the air to be replaced. In the end, I decided to use a small wall fan behind the stove to move the cold air from the room , allowing it to mix with the warm air being produced by the stove. Both rooms are far more comfortable now, and the leaks and drafts are minimized. This 1850's farm house was caulked, foamed, insulated to the hilt, and is still far from being tight. There was no sense in adding additional pressure on the envelope.

I vote OAK.

 

[Papelletman]

I agree with all the above, go oak and be done with it. Besides, when you drive your car where does the engine get its air from, out side or or the cabin!

 

[CapeMayDan]

Best Explanation of an OAK ever..
should be a Sticky

X2

 

[hinkle]

I have wondered if I pulled air from my basement if that would be better/worse than outside. Basement has a garage door and sand stone and gets cold in the winters. Saves a hole in the wall and can go through the floor vent.

30x30 cape cod, stove in room with steps to upstairs. cold air return and floor vent in the room with the stove. I know it pulls air from those when the stove is running, and the flame always runs strong.

 

[biomass burner]

I have wondered if I pulled air from my basement if that would be better/worse than outside. Basement has a garage door and sand stone and gets cold in the winters. Saves a hole in the wall and can go through the floor vent.

30x30 cape cod, stove in room with steps to upstairs. cold air return and floor vent in the room with the stove. I know it pulls air from those when the stove is running, and the flame always runs strong.

I have a brick ranch home with attached garage and was debating running a oak to my stove from the garage instead of another hole in the brick plenty of outside air gets through the garage doors but it wouldnt be as cold as directly from outside

 

[Pascal_Maertens]

Purchasing my first pellet stove. Have received conflicting advice on whether to arrange outside air intake for combustion vs allowing the stove to draw room air into combustion chamber. How important would this be in a typical residential installation? (Stoves considering are Harman XXV and Quadrafire Mt. Vernon AE)
Thank you.

I love this one


OAK or no OAK , I'll answer by a question, do you have an adjustable stove or not
Prior to get stoned, this is my own comprehension and opinion of why all North American stove needs to be hooked up to an OAK there is no North American stove that have an adjustable combustion fan, they are all static rpm depending on which power level they are set at example; you can change the rpm from the fan by changing power level from P1, P2, P3, P4 and P5 but you cannot change individually the rpm of P1,2,3,4 or P5 this is what make the Piazzetta and most European stove so remarkable not only they can change from 1000 to 3000rpm on each level but they also can change the convection fan rpm as well make it so much quieter in a living room.

• If you find one North American Stove that as adjustable combustion fan, please let me know.
• I’d like to mention that in some states, it’s a law and you need to refer to your own locality before applying any of these advices
  
  In Quebec I never hook up OAK, why will you ask? Its pure physic, houses are mostly all different but no one live in a bottle so no matter how your house is sealed there will always be air coming in. Another reason is that in Quebec province all new houses have to be hook to an air exchanger, believe me it does bring some fresh air in to. So why should I bring even more cold air in? If I’m in a sealed house all I need to do is to put more rpm to the exhaust or combustion fan to every level to reach the (Pa) score in accordance to the Piazzetta technical manual at programme line, 16P to 22P on programming sheet. This way my flame will be nicely vented, no lack of air = no soot, no problem and another satisfied customer.

What difference it make to have an adjustable combustion fan?
Poor air of combustion can be caused by many things

• House well sealed, need to raise the rpm combustion fan
• By obstruction, ash or soot need to be removed or cleaned
• Combustion fan rpm set to low, adjustments error in programme P16 to P22

We will see these adjustments further down in programming section

Poor air of combustion can cause many problems

• like we saw earlier soot on the door window
• soot outside on the exterior walls
• ash accumulation, causing NO LITGTING alarm
• pellets accumulation, causing dangerous backfire
• smoke and smells in the house
• poor anti-pollution
• poor heat performances
• low combustion

These are mostly all related or bring one to the other


On the other end having too much air of combustion can be caused by a poor sealed or insulated house and can also be a major source of problem;

• overheating alarm
• sending heat outside instead of keeping it inside a good stove you should be able to hold your hand at the chimney cap outlet without burning your finger
• hi rate of pellet burning
• poor performances

This post will not be the most popular here, but sure is going to give you a seconds taught,
and I'm sure I'll get goooood feed back on this post

This is a copy of my Sticky Post and its mostly Piazzetta related
https://www.hearth.com/talk/threads/piazzetta-pellets-stove-a-to-z-recommendations.147362/

 

[womaus]

• So why should I bring even more cold air in?

I believe this is the real question.

Why, if we do not live in a bottle, do we need to bring (i.e. "suck") more outside cold air into the house to compensate for the combustion of the stove? Does it not make more sense to bring in colder air from outside (with more condensed oxygen, better for the burn) straight to the stove than to use the already conditioned warmer interior climate air? To eliminate the conditioned (i.e. $$$$) air from the house?

 

[TonyVideo]

Unplug the stove like a power outage without an OAK and make your decision.

 

[Pascal_Maertens]

conditioned warmer interior climate air? To eliminate the conditioned air from the house?

You will always get new air in the house no matter what you do, so why would you want to put more unless you cant adjust the level of air, your stove really needs, well you have no other choice but to install an OAK and pray for that air to be just perfect for your stove. by the way, evolution did not came to all humain at the same time, same ting for stove companies but they all think they have the best way of doing tings... in the facts since 1985 most pellet stove have not evolve just copied each an other. beside, that now we have thermostat on them hooo!. we could stay here, all night arguing on this simple subject, and never get to an agreement. but this is my opinion I knew I would get some feed back and I'm glade it did. I live in north of Quebec we get temperature of -30 to -40 and the only time I put an OAK is when we sale none adjustable stove.

Regards
Pascal Maertens

 

[Pascal_Maertens]

Unplug the stove like a power outage without an OAK and make your decision.

Sorry but if you have installed your chimney according to the LEE chart your decision will remain the same, of course if you have ad your installation done direct vent by an idiot well now your going to be in trouble, well more like having 3 smokers at the same time in your house. I'll make you a nice video on this, it will be my pleasure it does happen a few time over here in the country.

 

[TonyVideo]

Many different stoves and installations. That is why I said to unplug it. If it smokes then install an oak. If needed yes adjust your exhaust accordingly. However some don't have any choice but a direct vent. In this type of install then an oak is imperative along with a UPS battery backup to aid in complete shutdown. To me the air has to come from somewhere and I would want to eliminate drafts in the house as much as possible for comfort alone. Oak would help.