insert in a zero clearance fireplace

[velvetfoot]

I get it now.

As an aside, I do have to say that the 2700i has been fine for us in our 2000 ft2 colonial.
7*F outside, 72* inside (1st flr).

 

[weezer4117]

hey folks! like others, i am new on the site. i also have a prefab (majestic) unit in my house. i have read this forum several times, and thanks to the good info provided i only have one question. if i dont install a top plate (sealing off the top of the chimney) how am i going to prevent 2 drafts? can i somehow block the bottom around my stanless, insulated liner? the innermost liner (of the prefab) is 8", with a liner and insulation this leaves some space between the liner and the opening of the 8" pipe. if this isnt somehow "sealed" then i will have a draft inside the stainless liner and outside of the stainless liner. not sure what to do here???

Wes

 

[kd460]

If I am following you correctly, then yes, you put a block off plate on the bottom of the chimney run or, another way to put is just above the insert. It gets screwed into the inside top of your prefab fireplace from the inside of the fireplace surrounding the liner that is poking thru into the fireplace.

It is probably easier to make your block off plate in two pieces and just overlap it a bit (it's easier to cut it with tin snips this way). Some kaowool and/or furnace cement to seal up the gap between the block off plate and the liner. I personally filled the 1/8 to 1/4 inch gap with kaowool and used some furnace cement between block off plate (kind of like a gasket) and the fireplace inside top, then mushed it all together with some screws. Has worked fine for 3 seasons so far. The kaowool expands a little when heated up so it seals a draft nicely, and the little gap gives you a little room for movement when things get hot and cold.

The bottom block off plate can be made from any decent type of sheet metal. Do a search as I think there is some type of template floating around, but it is nothing fancy, just to pieces of sheet metal with half of a slightly oval hole in them so when you over lap it a bit, the hole is round. If you feel you don't need to do the two piece thing then just a piece of sheet metal with a hole slightly larger than the outside diameter of your liner. Good luck. KD

 

[weezer4117]

thanks KD!! another idea that i am considering is installing a class a chimney. i will have to take out the innermost 8" liner of the existing prefab. my only hangup is how im going to support the weight of the class a chimney when it is sorounded by the other existing 12" liner in the majestic prefab chimney. would i have to remove the whole majestic chimney or is there a way to support the weight? (i really dont want to take out the outermost 12" pipe) i was thinking of using bricks under the tee or welding a shelf on the stove??? i know if i use bricks under the tee then i will have a hard time cleaning the pipe. believe it or not, the class a route would also be cheaper for me than a insulated liner. thanks, WG

 

[PeteD]

I would proceed with caution regarding inserts in a zero clearance fireplace. I had a 1993 Heatilator ZC prefab fireplace, model HD36B, GR4. I was checking into the smaller inserts and went to a local dealer to discuss the Regency I1200.

My ZC fireplace had a panel saying that an insert cannot be used, but I was under the impression that in more recent times (since 1993), inserts that are OK to be installed in these ZC fireplaces had been developed…

To get to the point, this installer (they are pretty big in my area) indicated that they do not install inserts into ZC units anymore that say it is not OK. They say they do not want to take chances and recently had an inspector in a local town reject the building permit to place an insert into a ZC fireplace. I did not want to be caught in insurance limbo.

Another side benefit to going with a new high-efficiency fireplace is that you can make sure everything is installed right.

This is what I found during demo:

Yep, a cardboard Heatilator box right on top of my existing ZC fireplace!

Good luck,
Pete

 

[weezer4117]

Pete-wow a cardboard box?! its a wonder u didnt have a fire.(if u used it) the install i want to do will not resemble a "insert" at all. i have built a special hearth out in front of the prefab. all i am using the existing unit for is venilation. the freestanding stove will not set inside the firebox AT ALL, it will be out in front of the unit. my toss up is using a stainless, insulated liner or a class a chimney. i know i would feel more safe with a class a (its also cheaper, believe it or not) my last post describes my delima with the class a, how i am going to support the weight of the new chimney if i leave the outer 12" liner in place??? thanks, WG

 

[monster_maul]

I am in a similar situation here, have a Factory Prefab Heatilator ZC fireplace, installed during new home construction in 1993. To add a little more complexity, mine is one of those dual sided units, sits between two rooms, finished on both sides. I am planning on removing the unit, installing a Woodstock, maybe the new Progress Hybrid on the hearth in front of one side.

My question for all of experts on this site,, is it acceptable, leagal to keep the existing Heatilator double wall air cooled 8" (at least 8") pipe, line it with a new 6" insulated SS liner? How is the existing Heatilator pipe supported? Does it rest on top of the ZC unit?

I've called a couple of on line companies that sell liner supplies, they've told me that it can be done,, one place told me that they sell something called a "Factory Built Liner Adapter" for this application. (http://www.chimney-liner-central.com/factory_built_liner_adaptor.html)

I'm a little unsure about the advice I've been given,, just because something can be done,, it may not meet all of the requirements for insurance purposes.

If I need to replace the Heatilator pipe, install new Class A pipe, can it be done without the job turning into a major construction project? It's a straight run, two stories, the existing pipe was built inside an internal chase, no entry/exit through floors.

I live in Northeast PA, if any one can recommend a good installer or contractor who does this kind of work, would appreciate it.