What is the correct way to tie a stove into your ductwork?

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Extremesolo

Member
Oct 30, 2008
8
Central, PA
I have a breckwell big E in the basement of my ranch house and while it heats up the basement fine, I am looking to get some more heat to the upstairs. I have the ductwork from my heat pump located within 8' of the stove. If I am trying to use the ductwork to help get the heat upstairs, do I want to get the heat into the supply or the return duct? Also I am thinking that maybe I need some vents in the floor to help with the air transfer and give the cold air somewhere to move to. Will cutting vents into the floor have a negative effect in the summer when I am cooling or can I just close the vents and stop the cool air? If cutting vents in the floor is the answer, how many vents should I cut and should they be in the living room, kitchen/dining room, bedrooms, bathroom, or in the hallway?
 
Check your local codes about natural draft vents. As for your duct work, I am not familiar with the Breckwell Big E. But I would run it to your supply air. Not the Cold Air Return. Make sure you put a "Backdraft Damper" at the start of the ductwork off your stove. So when you run the A/C in the summer you dont blow your air to the basement. And you will need another "Backdraft Damper" at the Furnace. I just bought a Fahrenhiet Endurance Furnace and am finally realizing what i got myself into. Once its said and done, it will be worth it. There are a couple members on here that have ductwork hooked to freestanding stoves like yours. I know of a Mt. Vernon (Quadrafire) and an Omega (Enviro). Both seem to work great and the users are happy with them. If they decide to post I will let them put there own 2 cents in. But people have done it and got it to work for them. Good luck and check your local codes.
 
The problem you might need to overcome with a pellet stove hooked to the duct is the output temps might be kind of high. Furnace's have high CFM blowers to move mass air at a lower temp of around 100ºF. Plus the bigE has a low CFM blower so you might have a volume issue depending on duct sizing. If you have existing duct, You might as well use it. Ducting isn't cheap to install. Also be aware not to connect the duct to the stove with screws as you still need to get to the heat exchanger cleaning rod. You'll have to make it removable or add some type of an access door.

DexterDay got most of the details for you, But I recommend installing a larger CFM blower to both lower the duct temps and raise the volume of output to get the air upstairs.

Here is my thread on my setup.

https://www.hearth.com/econtent/index.php/forums/viewthread/67884/
 
Hello

In the Laura & Veronica, there is the possibility to adjust the front and back air delivery by adjusting a lever.

More info on Ecoteck Laura 11kW Ducted Stove
Ducted Heating with wood pellets
Wood pellets are one of the few truly environmentally friendly ways to heat. Ducted stoves have a two extra warm air outputs at the rear of the unit and these can be connected to aluminum ducts routed other rooms in the property. A simple mechanical flap controls the ratio of air coming into the main room compared with the air being diverted to the back. All wood pellet stoves require a 13amp electrical connection.

For other stoves just bring the duct right up to the front of the stoves where the air exit the heat exchanger. That will also work well!
 

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Remember as pellet STOVE is a spot heater not a furnace. If you want a stove to do a furnace's jopb, buy a furnace. As people have attached duct to a stove and got some heat movement out of the unit but that is not what it is designed to do. Check your local codes and see what can be done. Remember if your toaster catches fire and when they come to inspect the damage they check everything, not just the kitchen. If you used a product against what the MFG intended it to do you could have issues.

Eric
 
kinsman stoves said:
Remember as pellet STOVE is a spot heater not a furnace. If you want a stove to do a furnace's jopb, buy a furnace. As people have attached duct to a stove and got some heat movement out of the unit but that is not what it is designed to do. Check your local codes and see what can be done. Remember if your toaster catches fire and when they come to inspect the damage they check everything, not just the kitchen. If you used a product against what the MFG intended it to do you could have issues.

Eric

Hello Kingsman

According to this URL the Laura and Veronica ARE classified as a "Wood Pellet Hot Air Furnace" So we are on the same page.
http://www.pelletstovefires.com/pellet-furnace.html
 
Don2222 said:
kinsman stoves said:
Remember as pellet STOVE is a spot heater not a furnace. If you want a stove to do a furnace's jopb, buy a furnace. As people have attached duct to a stove and got some heat movement out of the unit but that is not what it is designed to do. Check your local codes and see what can be done. Remember if your toaster catches fire and when they come to inspect the damage they check everything, not just the kitchen. If you used a product against what the MFG intended it to do you could have issues.

Eric

Hello Kingsman

According to this URL the Laura and Veronica ARE classified as a "Wood Pellet Hot Air Furnace" So we are on the same page.
http://www.pelletstovefires.com/pellet-furnace.html

I was not saying anything towards you. I have never heard or seen a "Laura and Veronica" so I know zero about them. I am sure their stoves or furnaces are very good

Eric
 
It seems to me that the only benefit of hooking up your basement stove to the house duct-work is to get heat circulating quickly. If speed is vital, it seems you could simply put a vent hole into the basement door and turn on the house heater fan. It would circulate the warmth to all the rooms that have heat vents. I became informed about that today after visiting the family that I helped by getting the pellet stove working in the house they just moved into. They had a Heating company look at the house because all the rooms were cold except the room with the pellet stove. They learned from him that a fan/blower control unit on a hall wall controlled an attic fan that sucked in air from the ceiling of the living room, and circulated it to all the other rooms. So the rising heat from the stove was the source of the house's "Central Heating" system. It doesn't work as fast as a duct-system furnace, but once it gets the temp up to desirable, then it's essentially the same as a faster heating system. With the fan working, they could sleep in their own bedrooms instead of in the living room. (it was 40 degrees the other night here)
 
j-takeman said:
The problem you might need to overcome with a pellet stove hooked to the duct is the output temps might be kind of high. Furnace's have high CFM blowers to move mass air at a lower temp of around 100ºF. Plus the bigE has a low CFM blower so you might have a volume issue depending on duct sizing. If you have existing duct, You might as well use it. Ducting isn't cheap to install. Also be aware not to connect the duct to the stove with screws as you still need to get to the heat exchanger cleaning rod. You'll have to make it removable or add some type of an access door.

DexterDay got most of the details for you, But I recommend installing a larger CFM blower to both lower the duct temps and raise the volume of output to get the air upstairs.

Here is my thread on my setup.

https://www.hearth.com/econtent/index.php/forums/viewthread/67884/

Just what part of the manual are you having trouble reading? Encouraging others to violate code and warranty is not a great idea.
 

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I'm sure no expert about air distribution ducts and possible danger from hot air being fed into them, but I can't see where the danger is if pellet stove convection air (not combustion air) is fed into a duct system post heater/furnace/heat exchanger as long as the system has a perfectly working fan to quickly move and dilute the air fed into the duct work. The only thing in its way is the vent grills that cover the vent openings in the floor or wall. The amount of air that a central air system moves would significantly dilute the air from the stove, otherwise it wouldn't have the power to move the necessary amount of air needed to warm/cool the multiple rooms of an entire house. I'm not trying to imply that there is a safe way to directly connect duct work to the face of the convection tubes, there may be, or maybe there isn't, but capturing the air output into a hood turned horizontally seems like a perfectly safe thing to do. So the word "connect" should be taken to mean literally connected.

As for the warning "Caution: Do not connect to any air distribution duct or system", it treats the reader like he's brain-dead and doesn't have the intelligence to ask "Why?" much less understand the answer. Not a word of explanation, limitation, or qualification. It's so great to be treated like a stupid child. I sense lawyers behind most product warnings, not engineers only, and what's the word that fits many of them? Oh yeah, Boilerplate. And how about the warning that the "use of any replacement parts not recommended by the manufacturer is prohibited" don't manufacturers only recommend the parts that they use and SELL?! Do they really recommend parts from competitors if they pass muster? Have you ever heard of a auto manufacturer or car dealer repair garage doing that? I think not. But don't forget that the Chinese are turning out counterfeit parts for all kinds of things. Buyer beware.
 
arnash said:
As for the warning "Caution: Do not connect to any air distribution duct or system", it treats the reader like he's brain-dead and doesn't have the intelligence to ask "Why?" much less understand the answer. Not a word of explanation, limitation, or qualification. It's so great to be treated like a stupid child. I sense lawyers behind most product warnings, not engineers only, and what's the word that fits many of them? Oh yeah, Boilerplate. And how about the warning that the "use of any replacement parts not recommended by the manufacturer is prohibited" don't manufacturers only recommend the parts that they use and SELL?! Do they really recommend parts from competitors if they pass muster? Have you ever heard of a auto manufacturer or car dealer repair garage doing that? I think not. But don't forget that the Chinese are turning out counterfeit parts for all kinds of things. Buyer beware.

My Lopi has output temperatures in 400 degree range on the highest settings. Think about all the clearances listed on your stove, especially in front of the stove now picture ductwork in the house and things that might be over heater ducts. Imagine a toddler plopping his naked but down onto a 250 degree heat register. Many houses use wall studs and floor joists as part of the ducting. What is the high limit for such non-metal ductwork? I have nary a clue but I bet your pellet stove output temperature exceeds it.

Sure, you can rig up your own system and keep the system at safe temperatures but what happens when your system fails? What turns the stove off if the temperature at the heat registers could potentially be excessive.

Nothing. That is the reason the manufacturer tells you not to hook the stove to the ductwork of the house.

In reality the danger factor is low but I feel it's reasonable for the heater manufacturer to place that sentence in their installation manual as a suggestion to the reader and to cover their butts.
 
If you have a forced air system as most people do, run a new return air duct into the room with your stove block off the old one and run the furnace on circulate. You can probably use your thermostat if its in the right place, or hook up a new thermostat in another location. As was said earlier, a free standing stove is a big space heater. Its like buying a japanese bike and putting different pipes on it to make it sound like a Harley.
 
Rather than tying into existing ducting, why not use dedicated heat/return ducts with your existing stove? Your stove blower is not nearly powerful enough to pump hot air through a whole-house HVAC system, that simply won't work. You would need to do some serious modification to your stove to accomplish such a task, of course that would void warranties. Code issues also come into play, if you don't know what you're doing you could be putting yourself and everyone else within your residence in danger.

Another option that has been mentioned already: look into a pellet furnace if you desire to tie into existing duct work, or use a dedicated duct system just for the pellet furnace (like I did). It's expensive and somewhat complicated to tie into existing ductwork due to the backdraft dampers required. Also, most modern high efficiency furnaces are finicky about air pressure within the HVAC system, so altering the duct work could cause serious issues with your furnace's heat and A/C capabilities. I looked into tying into my existing HVAC at first, but the cost was ridiculous to do so, I was far better off running dedicated heat and return ducts for my Fahrenheit pellet furnace.

I posted a thread with photos of how I installed my own duct work for my Fahrenheit unit, it was not difficult to do. Just make sure you follow manufacturer's specs on minimum duct size, etc. I ended up branching a main 10" heat duct into two 8" ducts and installed two 12x20" heat registers in my great room. Complicated HVAC calculations based on cfm are required for determining how to properly install a duct system. I installed a return on the opposite side of my great room to encourage a nice, convective airflow through my large great room. The furnace supplies enough heat to warm my entire 2500 sq. ft. house within 1-2 hours.

Here is my post w/photos:

https://www.hearth.com/econtent/index.php/forums/viewthread/67125/P22/#780426
 
BeGreen said:
j-takeman said:
The problem you might need to overcome with a pellet stove hooked to the duct is the output temps might be kind of high. Furnace's have high CFM blowers to move mass air at a lower temp of around 100ºF. Plus the bigE has a low CFM blower so you might have a volume issue depending on duct sizing. If you have existing duct, You might as well use it. Ducting isn't cheap to install. Also be aware not to connect the duct to the stove with screws as you still need to get to the heat exchanger cleaning rod. You'll have to make it removable or add some type of an access door.

DexterDay got most of the details for you, But I recommend installing a larger CFM blower to both lower the duct temps and raise the volume of output to get the air upstairs.

Here is my thread on my setup.

https://www.hearth.com/econtent/index.php/forums/viewthread/67884/

Just what part of the manual are you having trouble reading? Encouraging others to violate code and warranty is not a great idea.
Added the disclaimer!
These mods to my stove are not recommended by the stove gods! So don't do as I do.

What manual did you pull the quote from?
 
Checkthisout said:
arnash said:
As for the warning "Caution: Do not connect to any air distribution duct or system", it treats the reader like he's brain-dead and doesn't have the intelligence to ask "Why?" much less understand the answer. Not a word of explanation, limitation, or qualification. It's so great to be treated like a stupid child. I sense lawyers behind most product warnings, not engineers only, and what's the word that fits many of them? Oh yeah, Boilerplate. And how about the warning that the "use of any replacement parts not recommended by the manufacturer is prohibited" don't manufacturers only recommend the parts that they use and SELL?! Do they really recommend parts from competitors if they pass muster? Have you ever heard of a auto manufacturer or car dealer repair garage doing that? I think not. But don't forget that the Chinese are turning out counterfeit parts for all kinds of things. Buyer beware.

My Lopi has output temperatures in 400 degree range on the highest settings. Think about all the clearances listed on your stove, especially in front of the stove now picture ductwork in the house and things that might be over heater ducts. Imagine a toddler plopping his naked but down onto a 250 degree heat register. Many houses use wall studs and floor joists as part of the ducting. What is the high limit for such non-metal ductwork? I have nary a clue but I bet your pellet stove output temperature exceeds it.

Sure, you can rig up your own system and keep the system at safe temperatures but what happens when your system fails? What turns the stove off if the temperature at the heat registers could potentially be excessive.

Nothing. That is the reason the manufacturer tells you not to hook the stove to the ductwork of the house.

In reality the danger factor is low but I feel it's reasonable for the heater manufacturer to place that sentence in their installation manual as a suggestion to the reader and to cover their butts.

Why should they have to explain to you why you shouldn't hook up ductwork? Their engineers have designed the stove to comply with a list of design parameters. One parameter is there will be a certain amount of heat removed from the stove. Adding ductwork restricts the stoves ability to discharge heat which in turn can cause overheating. If the stove overheats, the best case is the stoves hi-temp limit switch shuts it down. Worse case is your house starts burning. The stove manufacturers are just protecting the stove owners from themselves.

I bet the pellet stove industry has lots of stories about geniuses who burned their house to the ground due to faulty installations or modifications such installing ductwork.
 
Then trying to sue the stove Mfg. for faulty design.

Eric
 
The reason the stove manufacturers don't want any connections to duct work is to protect the masses of idiots out there.
I think its only through innovative tinkering that the next product gets developed. The pellet stove makers seem like a pretty
conservative bunch. Look into coal stoves if you want to see a group of back room tinkerers, stoves with full heat jackets,
removing blowers to rooms below the stove for quieter stoves, the list goes on and on. Check out the coal stove makers web
sites, they can be custom ordered with ducting and blowers, and coal stoves put out 90k, 120k plus BTU's. I see nothing wrong
with a little yankee ingenuity.
 
Sometimes they write the manuals for more than just idiots. They write it taking into account failure modes. In a perfect designed system with duct work it may work fine. What happens when a blower bearing seizes? Does the stove shutdown before any duct related damage can occur? Always do "what ifs" on different worst case conditions. They may happen rarely, but all it takes is once to occur with the worst case conditions and stuff goes bad.
 
I like the idea of a pellet furnace with dedicated ductwork. Though this becomes less practical if your basement ceiling is finished.
 
IMHO, I had a better chance of burning my house down with the smoke dragon I used before the pellet stove. How many over fire safetys do wood stoves have?

You boys need to look at the stoves that do have ducting allowed and see if there are any safeties or Precautions added. They only have one thing that stands out. MORE CFM"S to cool the convection air. Same as a pellet furnace. And a small feature I added to mine. Sealed convection path to the blower. Hanging duct in front may have draw backs. Smoke and dust can enter the venting with it hanging in front of the stove. A sealed path will reduce this.

Yes I agree that going with a furnace to duct the heat to where you need it is the best route. But until someone can point me to a safety feature I missed. My duct stays connected!
 
j-takeman,
You are right. The thing that makes them work is more cfms to reduce the temperature and also the proper size pipe. You did the mods to make yours function correctly. I agree about the over-fire with the wood stove furnaces that I see for sale. Just a loss of electricity can cause a problem and that is the biggest concern I have. Pellet stoves don't have that problem. A run away fire will get shutdown by the temperature over limit.
 
You have almost 500 CFM in your stove now, pretty close to a furnace size blower.(Person in Question?). My Fahrenheit only has 800 (Pellet Furnace). My Quad freestanding is 160 CFM. The Enviro Maxx (blower in question) also has 20,000 more BTU's than the Fahrenheit does also. Smaller blower, more heat output. So you have more than double, almost triple the CFM than any ordinary "Freestanding" pellet stove. I would say that your convection temps dropped significantly when you changed blowers. Thereby decreasing any chance of failure to any of the parts. I AM NOT RECOMMENDING ANYONE TO DO THIS, in any way shape or form. But I am sure that the person in question, has taken any and all necessary steps to avoid any catastrophic failures of any component used in his set-up. The "Said Gentleman" has been operating pellet stoves for quite some time. Half the reason I became a member, besides the helpful advice, was to see what everyone else had and did in there set-up to increase the heat output and overall efficiency of there stoves. I am not trying to bash anyone or pick sides. There have been many other threads on "Mods" done to there stoves. Everyone that reads them at home, Should know better than to just do anything out of the ordinary on a whimsical note. These stoves have warranties and are kept only by leaving them "Stock". Those that do modify, know that they are undertaking any and all responsibility to the stove and damage within. Wood Stoves have there downfalls also. There have been many more stories of a house burning down to Wood fires, than there have been of pellet stoves. I'm not saying it doesn't happen, but there are many safety devices put in place to help avoid any catastrophic events from occurring.

Not picking sides, I see both points validly. Void your warranty and run the risk of something happening. Or try to get the most efficient and cheapest way of heating. Every ones needs and set-ups are different. Again. I am not implying that this is acceptable either. I don't condone anyone doing this (Just as person in question stated)

Just wanted to add my 2 cents. Cheers everyone. Oh, and smile, its a Beautiful day. 30 degrees and stove is chugging along.
 
"Adding duct-work restricts the stoves ability to discharge heat which in turn can cause overheating" I don't see how one could conclude that duct-work restricts the convection blower air discharge in any way, only obstructions can do that.

"If you have a forced air system as most people do, run a new return air duct into the room with your stove, block off the old one and run the furnace on circulate. " Sounds like the perfect solution, and with a heat intake duct facing the stove heat tubes, and the furnace circulation fan running, the pellet stove heat would be diluted enough that it would only be warm when it reached a room vent. When I stand in front of my stove when it is as hot as it gets, it's too hot if I'm only 1 foot away, but if I'm 2 feet away the heat is very mild. So distance and dilution make a huge difference in stove heat temperature.
 
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