Converting fireplace to woodstove

[ChuckinVa]

We have lost power several times this winter for extended periods and needed to come up with a solution to provide heat as our heat pump has zero value at that time. We found a Vermont castings Aspen wood stove on CL and bought it this week. Now I need to cover the front of the fireplace with 'something" non combustible ( I'm thinking sheet metal) and have a 6" hole cut in it to put the stove pipe through it. I'm thinking about getting a heating and air company next to where I work to fabricate something for me and cut the hole. What I'm wondering is 1) how to attach it to the fireplace so that I don't get any air leaks.Ie some type of duct seal 2) should I put a damper in the stove pipe as I will not have access to the fireplace damper after I put the cover across the front of the fireplace.3) is it Ok to just put the stove pipe through the metal or should I put a 90 on the end of it to turn it up to the flue? I'm looking forward to new ideas or suggestions.
Thanks,
CHUCK

[Fred_47460]

I actually asked this question at a local wood stove store. The response was....if THEY installed the stove....they would run a pipe all the way up through the chimney and out the top where they would install a cap to keep the rain out. The idea being to make sure there's not a place for creosote to build up and cause a fire. The fellow (owner of the store) said that when the fireplace inserts first came out they had a short stub pointing up into the chimney. As the fire burned it deposited creosote on the relatively cooler masonry....and as time went by the creosote would eventually catch fire and possibly burn the house down.

[Redoverfarm]

Chuck that is pretty common practice here.  As Fred stated there is a problem with the build-up but not that much more than a regular mason flue.  Not sure what type of flue you have now ( Mason or fabricated) but I would opt to put at least a 45/90 deg up swing to the fireplace damper if it were mason constructed and probably 90 if it was a fabricated flue into the bottom of that.

The plate I think I would want something heavier than standard heat/cool material.  Probably at least 1/8" plate.  You can purchase the regular stove gasket material at most hardware which I would run around the exterior edges of the plate to seal the air off from the flue.  It will not only provide cold air entering the house, smoke also but will also keep the stove from drawing more than normal and extend the burn time to your wood.  You will need to make this convertible in the fact that you will need to periodically remove the shield and clean the firebox/flue.

Depending on the configuration of your flue pipe out of the stove but you can place an in-line damper in either the horizontal or verticle flue pipe prior to entering the firebox. Like those that are pictured here.

http://www.woodstove-outlet.com/woodstove/spipedamp.htm

Or you can put a damper extension onto your existing damper handle such as those pictured in this web page near the bottom under damper handles.

http://www.chimneysupply.com/?x

[ChuckinVa]

Fred, I think our gas log store told us that same thing about adding gas logs several years ago. I think they want to be sure that what they are involved in reduces their liability or risk to as near zero as they can. I know that if you burn wood, you have to maintain the system or you will have a chimney fire. Period. That means regular cleaning and inspection and burning good quality wood. I will certainly make sure we do that as I have no desire to burn our house down.

John, I believe the 1/8 " plate is a good idea maybe 1/4 ". I was wondering about the galvanized finish on the sheet metal off gassing anyway.The flue is fabricated, not masonry.
There is a metal works over in Broadway, Va that can probably take care of that for me. I just need to make a template or measure everything out. I had forgotten about the stove gasket  material. That should be simple enough to find over in the valley at one of the Ace hardware stores. I think I will put the damper in the stove pipe as it will be easier to do it that way.

Thanks for the replies.
CHUCK

[glenn kangiser]

I agree with John on this.  I used to build wood stoves and fireplace insert wood stoves in my shop.  A friend in Oregon was the inventor and manufactured kits of parts.  We used a removable steel cover for the fireplace opening blocking it vertically at the front of the face of the fireplace.  It seems we did not have a standard size as each one had to be custom fit to each fireplace.  I am sure it was not over 1/8 inch thick - 10ga. but we may have had a shop break an angle on the sides for added strength.

You could put angle clips on each side, and top and or bottom with bolts to tighten and lock it to the sides of the brick, setting it back an inch or two in the opening.

We left the fireplace damper open and did not use a damper on the stove as our stoves were air tight and did not need a damper.  We had bottom fire air -central fire air and over fire air , all which could be shut off.  For a fast start the ash pan could be open a bit.  We also did not do more than stub the pipe back under the fireplace opening.  They worked great that way and every one loved them.  As John mentioned - clean the fireplace flue once in a while.  That was in about 1976 and I know of some that are still in use today.  The way they were built I assume most of them remain serviceable.  They had a firebrick lining  and the fire was built on firebricks over the removable ash pan.  They were gapped so air could get under the fire.

[miman]

go the the vemont castings web site.  download the manual for the aspen. the manual should answer all your questions.

[kenhill]

For us with a wood stove insert, the faceplate was not enough.  It would still radiate cold when we would be -20 to 10 degrees F.  After having the great Alaska Energy Audit, it was recommended that we pack the the area around the stove and around stove pipe passing through the chimney flue with rock wool.  I used a some sort of "caulk" meant for high temperatures around the sheet metal faceplate.  Our house is 30 years old, so the chase is not insulated or sealed off.  

This made an amazing difference.  When they did the blower test again, there was not a gale force wind coming from around the fireplace.

[ChuckinVa]

Thanks for the additional comments. I have the VC Aspen manual but it does not address this specific type of installation, only the clearances etc. I was thinking that it might be worthwhile to have some insulation sandwiched between two steel plates but I'm not sure I have enough room where I am attaching the plate to put any significant amount of insulation. I did determine that I can work the damper after I install the plate which would allow me to close off the air coming to the stove from the outside.
CHUCK

[glenn kangiser]

I have used Fiberglass around buried stove pipes with no problem.  If it was a place that got red hot it may melt a bit but I haven't seen that happen.