Grandpa Bear Install Into Existing Fire Place

[arodrigz]

Hi all, just moved into an older but well maintained farm house. It has a fireplace in the living room that I'm wanting to put a stove in front of and utilize the existing flue. However, my big problem is that the height of the fireplace is 24". The rear venting Grandpa bear is approximately 28"

I'm going to install flexible SS pipe throughout the length of the Chimney but, when I come out of the chimney and into the Fireplace box the only way to attach to the stove is if I come out of the fireplace and angle slightly up into the rear of the stove. The problem that I see with this is that there will be a 4" dip downwards coming out of the stove then once clearing the front of the fire place it would angle back up.

What effect would this have on the draft if any? Are there other issues that I need to consider?

I may be able to put in an insert but my in-laws have a grandpa bear and I love the way it heats so wanted to put one in our home.

thanks
Alex

 

[coaly]

Is it on a masonry or stone pad? It should have at least 6 inch legs. Some were longer. As long as the floor protection is there, cut down the legs leaving a minimum of 3 inches air space. Many times only the rear legs need to be cut. Make sure you have enough floor protection in front of stove. See manual for correct Grandpa model. Are you reducing to 6 inch liner, or using 8" ? If inspection is necessary, code will not allow reduction, although it will physically work. Reducing right at stove collar will give the extra inch you need. Reducing will only affect open door burning if you have a screen and are planning on that. Many are reduced and open burn with no problem, depends on chimney draft. You should be fine with a liner especially if insulated.

 

[arodrigz]

I'm not really sure what is underneath the hearth. Here is a picture with dimensions of my fireplace.

 

[arodrigz]

Here is a crude drawing of what the setup would have to look like and what Coaly above is suggesting. The only thing I don't like about cutting the rear legs down is that I will no longer have a flat parallel surface on the top of the stove to set things on, etc.

Will I have any problems with simply using the stainless liner that I'm putting in and flexing it around and up to the stove. It does put that dip in there but other than becoming a creosote trap, will it effect the running of the stove?

 

[coaly]

The stove remains level. Hearth is extended with stove board or hearth extension pad sold for that purpose. Front legs then drop down to floor level. You don't have much of a pad there. When you have a fireplace with a higher shelf, like built up stone, it takes bricks under the front legs to level. You have to know what floor protection the existing hearth extension is, or add a UL stove board over it and use a matching hearth extension on the floor.
If that is solid brick, a metal shield with at least 1 inch airspace under the stove makes a huge difference. (If you don't have a newer model with shield)
Here's the airflow for a much cooler floor; I would add to floor protection this way when modifying leg length. The sample pictured is a VI Model that has double 16 Ga. on the bottom with 1 1/2" overall airspace.



Can't tell what the mantel is made of, but by your diagram, you're going to need a deflector shield for it as well. (A standard part with Insert installation as well) Another reason to bring the stove out from hearth.
Much easier and cheaper to use an Insert with your hearth.

 

[CamFan]

In your case you would cut both the rear and front legs. I have installed a mama in a shop, I had to elbow down then out the wall. It smoked back when I started the fire but once it started to draw all was fine. You have some dark soot marks on the brick in your picture. If it is not a great drawing chimney then it may not work. What you can do is install it with the stainless liner. Keeping in mind having the 16" protection in front of the stove and knowing that the hearth is not thin brick on the wood. If it does not draw to suit you then use a jack to raise the stove and cut each leg using a sawzall or portable band saw. If you raise one leg at a time then you can do this with out removing the stove.
good luck

 

[arodrigz]

Ok, change of plans. I'm scrapping the Grandpa Bear idea because it was getting too complicated and I ran into a sweet deal on a Fisher insert that I could not pass up. The dimensions work perfect for the opening. However, I'm stumped with one item. I'm planning on dropping a SS liner but the Fisher insert does not have a flue lip to attach to. The flue opening on the stove is approximately 8" but it is flush to the top of the stove. I'm used to free standing units where the stove pipe hooks into the flue liner lip but this stove doesn't have one. So what am I missing here? Here's a picture of what I'm referring to. How do I attach the liner to this? Is there an adapter that snuggly fits into the flue creating a collar for the SS pipe to attach to?

 

[coaly]

Use the search box at top and search "Insert Boot" in this Forum.

They were originally designed to set in the hearth and seal the front cover plate around the sides to prevent air leakage into the low pressure area of the chimney flue. The insert needed to be removed each time the flue was cleaned, so the boot allows connection to a liner and is the best way to go. You have to modify one, or make your own to notch around damper rod.
Here's a current thread picturing a perfect example of an insert installation including baffle plate and boot;
https://www.hearth.com/talk/threads/fisher-fireplace-insert-project.124182/