Harman Invincible Insert

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jsahara24

Member
Feb 21, 2014
20
Kutztown, PA
Hello Everyone,

This is my first post, although I've been lurking around these forums for some time now.

I live near Allentown Pennsylvania, and I am in the middle of building a cabin in upstate NY. The cabin is a single story with a cathedral ceiling, and is basically cut in half. One half is completely open concept, the other half is 4 bedrooms, laundry and a bathroom with a loft above it. It is 1400 SF (28x50) and it is attached to an existing 300 SF cabin (12x24).

I had been considering a pellet stove and a friend was moving and needed to get rid of an older Harman Invincible Insert, which he has rebuilt all the motors. After some research I found that while it is an older stove without an auto light feature, it is a workhorse that should provide me with many years of warmth in the harsh climate! For 200$ it seemed like I couldn't go wrong, so I bought it.

So now I have basically completed the framing of the cabin, and the time has come to install the pellet stove. My concern/issue is relating to either constructing a "fireplace" to install the pellet stove into, or coming up with another way to install this unit. I had planned on installing the insert in the corner of cabin where the living room connects to the bedrooms, along with the porch. However it has me wondering how to run the vent, install a "fireplace", and whether any heat will make it back to the bedrooms.

See attached for a picture of the layout, and a picture of the room it is to be installed in. I've found some pictures of nice corner insert installs, however they seem to run all the way up to the ceiling. I would prefer to avoid cutting any holes in my ceiling due to the massive amounts of snow we get each year. Average is 250 inches, so leaking is a major concern. I also have the porch to deal when trying to vent it through the wall.





Any advice would be greatly appreciated, and if additional pictures would help you visual it I have pictures of almost every angle! Thanks for the help!

Jason
 
i think your idea is a fine one. corner "zero clearance" fireplace in corner along shared wall with bedrooms..vent up through roof..fairly straight forward. loft is gonna be pretty toasty. might want to come up with a way to move air from the back of the loft area down somehow...into the hall shared by bedrooms and bathroom would be sweet, but i do not have any "good" ideas on how to pull that off. i think Kutztown is home of the World's Largest General Store, no? They prolly have something for that, lol. Good luck, that stove is a tank...very aptly named...invincible.
 
Nice place, nice price on the insert ... does the Invincible come with the zero clearance cabinet or is that yet to be purchased? Usually installing an OAK will reduce clearances to windows/doors. Check your manual. http://hearthnhome.com/downloads/installManuals/Invincible_Insert.pdf

Corner install would work well. For myself, I would almost consider not putting in the center window on the wall opposite the deck to create a focal point for the room and to allow heat flow to both kitchen and bedrooms. Which direction is south so you can capture the most natural light? Might want to consider a large ceiling fan in the peak to push heat back down from the ceiling.

Keep us posted on your project...
 
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i think your idea is a fine one. corner "zero clearance" fireplace in corner along shared wall with bedrooms..vent up through roof..fairly straight forward. loft is gonna be pretty toasty. might want to come up with a way to move air from the back of the loft area down somehow...into the hall shared by bedrooms and bathroom would be sweet, but i do not have any "good" ideas on how to pull that off. i think Kutztown is home of the World's Largest General Store, no? They prolly have something for that, lol. Good luck, that stove is a tank...very aptly named...invincible.

I wish I had a picture, but I do have the mounting shell for the stove.

My issue is that I don't want to put the exhaust through the roof, everyone that I talk to from my camps area says to avoid holes in the roof b/c of all the snow they get. Before I talked to them I installed a wood stove through the roof on my barn and it hasn't leaked but that has shingles, this has a metal roof so I believe its more difficult to flash.....

So I was thinking about trying to vent it through the wall, perhaps out the side of the porch. I know with a wood stove you need a good draft, but these have a fan to push the exhaust so I believe their is more leeway? Im not positive.

I believe the official "worlds largest general store" is in Lehighton or jim Thorpe? I think there might be one around here too, seems to be more than one?!? haha...

I like the idea of getting heat into the hallway through the loft, I'm concerned about the temperatures in the loft. I have some large fans planned....
 
Nice place, nice price on the insert ... does the Invincible come with the zero clearance cabinet or is that yet to be purchased? Usually installing an OAK will reduce clearances to windows/doors. Check your manual. http://hearthnhome.com/downloads/installManuals/Invincible_Insert.pdf

Corner install would work well. For myself, I would almost consider not putting in the center window on the wall opposite the deck to create a focal point for the room and to allow heat flow to both kitchen and bedrooms. Which direction is south so you can capture the most natural light? Might want to consider a large ceiling fan in the peak to push heat back down from the ceiling.

Keep us posted on your project...

Thank you, I'll be honest im not sure what the zero clearance cabinet is. In the link you gave me I have what they call the mounting shell, is this what you are talking about or do I need to get something different? I was planning on framing it with wood and then putting up cement board and then facing it with stone....

I will read through the manual this weekend, thanks for that link!

The floor plan I posted is slightly different that what actually got built. The wall you are talking about got a French door closest to the bedrooms, and one large window in between the existing building and the French doors. I am planning on 2 large fans in the main living area, and at least one in the loft. The ceiling in the loft is approximately 9' and it will slope down to about 4' so its a definite concern....I don't mind sleeping in cooler temperatures, but I can stand sleeping in too hot....
 
Was just poking around on the Harman site and not sure if you can get a zero-clearance cabinet for the Invincible (can for the Accentra). It is a metal cabinet that the mounting shell goes into and eliminates the need for cement board. Check with your local building official to ensure what you are planning is compliant.... keeps the insurance company happy too.

What elevation is the cabin - are you in the Adironacks? If your elevation is over 3000, you need to increase diameter of venting to 4". Also, if equivalent vertical length is over 15, 4" should be used. The below is just one site at random that addresses this ... there are others.

"A rule of thumb equation we are using has been adopted by most pellet manufactures. The equation is called the sum of Equivalent Vertical Length (EVL). All of the above mentioned venting restrictions have been assigned EVL values as follows:
  1. Each 45 degree elbow = 3 EVL
  2. Each 90 degree elbow and Tees with cleanout = 5 EVL
  3. Each foot of horizontal run = 1 EVL
  4. Each foot of Vertical run = 0.5 EVL
  5. Elevations above 3000 ft with an EVL of 7 must adapt to 4 inch vent pipe.
If your installation is below 3000ft, we would need to do some math. The rule of thumb equations is that if the sum of the EVL is 15 or greater, then the pellet vent pipe would be increased to 4 inch diameter pellet vent pipe."
from: http://nevelsstoves.com/pellet-stove-venting.html

Hope this helps...
 
The shell that you refer to is designed to be anchored on both the top and bottom and it needs to be a rigid mount setup so it can't move unless whatever you come up with allows you to perform all the maintenance needed such as the flue pipe cleaning. I've never seen any mention of putting a OAK on a Invincible insert.

Very good price for that stove. Make sure you give it a complete cleaning, especially the side air chambers and the blower motor that is on the underneath of the unit. If you have any questions that your friend can't answer ask here as there are a number of Invincible owners here.
 
Checked the manual - air intake comes from front bottom - no OAK. First generation insert? Was just thinking in terms of large windows and doors for the scenic view, OAK would reduce clearances but not an option for this situation.
 
you could vent it out the side of the porch. that shouldn't be a problem with a 4" vent. I dont think they built a ZC (zero clearance) box for that. You'll have to built the enclosure so that its concrete board/dura-rock or other type of non-combustible on the inside. You have crystal cave...I knew I had been to Kutztown. I was thinking of the place in Lehighton....Crystal Cave much cooler (literally and figuratively).
 
Was just poking around on the Harman site and not sure if you can get a zero-clearance cabinet for the Invincible (can for the Accentra). It is a metal cabinet that the mounting shell goes into and eliminates the need for cement board. Check with your local building official to ensure what you are planning is compliant.... keeps the insurance company happy too.

What elevation is the cabin - are you in the Adironacks? If your elevation is over 3000, you need to increase diameter of venting to 4". Also, if equivalent vertical length is over 15, 4" should be used. The below is just one site at random that addresses this ... there are others.

"A rule of thumb equation we are using has been adopted by most pellet manufactures. The equation is called the sum of Equivalent Vertical Length (EVL). All of the above mentioned venting restrictions have been assigned EVL values as follows:
  1. Each 45 degree elbow = 3 EVL
  2. Each 90 degree elbow and Tees with cleanout = 5 EVL
  3. Each foot of horizontal run = 1 EVL
  4. Each foot of Vertical run = 0.5 EVL
  5. Elevations above 3000 ft with an EVL of 7 must adapt to 4 inch vent pipe.
If your installation is below 3000ft, we would need to do some math. The rule of thumb equations is that if the sum of the EVL is 15 or greater, then the pellet vent pipe would be increased to 4 inch diameter pellet vent pipe."
from: http://nevelsstoves.com/pellet-stove-venting.html

Hope this helps...

It sure does, thanks.

I'm west of the Adirondacks in the tug hill, about 1000 feet.

The way I would like to vent it, out the side of the porch, would require 3 90*, about 8 feet vertical, 4 feet horizontal. So that would be 23, would 4" be enough for that?
 
The shell that you refer to is designed to be anchored on both the top and bottom and it needs to be a rigid mount setup so it can't move unless whatever you come up with allows you to perform all the maintenance needed such as the flue pipe cleaning. I've never seen any mention of putting a OAK on a Invincible insert.

Very good price for that stove. Make sure you give it a complete cleaning, especially the side air chambers and the blower motor that is on the underneath of the unit. If you have any questions that your friend can't answer ask here as there are a number of Invincible owners here.

Thanks. I've heard good things about it from my buddy, I'm concerned about how well it will warm the place up when I get there and its 10* out.

I found this picture on the internet and I'm going to try to follow this general idea but make it my own.

 
you could vent it out the side of the porch. that shouldn't be a problem with a 4" vent. I dont think they built a ZC (zero clearance) box for that. You'll have to built the enclosure so that its concrete board/dura-rock or other type of non-combustible on the inside. You have crystal cave...I knew I had been to Kutztown. I was thinking of the place in Lehighton....Crystal Cave much cooler (literally and figuratively).

We do have crystal cave, my brother is a teacher and he used to give tours in the summer. Neat place.

I was planning on building the frame with wood and then cement board and stone. I should probably use double wall pipe especially when I go through the wall and porch.
 
4" is what you need. Double wall pellet venting and may have to meet special requirements depending on how you build it since it's not a traditional fireplace install or free-standing with exposed venting. Kind of like measuring twice/cut once - check what you need to do to meet code from the source so you don't run into problems later. Choose a good quality pipe and seal well.
 
image.jpg What you want to do is very doable. Here is a pic of my 18 year old Invincible living out its later years at my camp in Maine. Burning strong this morning.....
 
Thanks to everyone for the advice! I'll probably start the install in the beginning of April when the snow melts and I can carry my supplies in....In the mean time im going to run by my local stove shop and get an idea on necessary supplies and costs. I'll be sure to post back with any updates or questions....
 
Well I'm back and way behind schedule! I was at camp last weekend and started framing for my fireplace. My plan goes something like this, any advice would be appreciated....

I am framing the pellet stove fireplace with 2x8s from the floor to the ceiling of the building, approximately 12' at the highest point. I left an opening with a header above the opening for the pellet stove (Harman invincible insert). Below it I am building a platform approximately 8 inches off the ground with 2x6's with cement board and flagstone. I am good with the framing aspect of the project but im a little skeptical about the "fireproofing" portion.

I installed a wood stove in my barn and used two layers of cement board with a 1" air space between them on the wall behind the wood stove. The air space really seems to help dissipate the heat, however with a pellet stove I do not believe the temperatures get anywhere near a wood stove. So I am wondering if installing the cement board directly onto the framing is adequate to dissipate any heat that will be generated from the sides and back of the pellet stove? Or do I need to install plywood first and then the cement board? Or should I have an air space between any wood and the cement board? I am also wondering if I need to install cement board along the entire inside walls of the "closed" fireplace to protect the walls from the stove heat and the flue pipe or can I use 5/8 firerated drywall?

I have the manual and it doesn't say anything about clearances and im not sure if cement board on studs, or plywood, is adequate for my install.

Hopefully I was clear enough, I am heading up to camp again this weekend and will get some pictures but would like to continue my installation. Any advice is greatly appreciated!

Thanks,
Jason
 
I believe the Invincible insert was designed to be installed in an existing masonry chimney. It appears you are doing a zero clearance style chimney. Hopefully someone else can chime in if they have done something similar.
http://hearthnhome.com/downloads/installManuals/Invincible_Insert.pdf
http://hearthnhome.com/downloads/installManuals/invincible-insert_part2.pdf

Thanks, I am trying to build a ZC style chimey and I am unclear whether cement board attached directly to 2x6's or plywood is considered non-combustible. Or do I need an air space? I know pellet stoves don't offer radiant heat, so I think I will be OK, I was just looking for some re-assurance.

Any help is appreciated. Jason
 
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