Follow Up to Insert/ZC Problems

[OregonCountry]

Hi There,

Thanks Craigi, KD, and Better Safe than Sorry.

I will try to find out more answers but this is what I have. This is a zero clearance (before the woodstove was installed). It had glass front doors which were removed for the wood stove. And yes, the back of it is some sort of ceramic/brick-looking material. The piece they installed over the crack (and the install of the plate completely covered the back of the zero clearance which included the crack) was 1/4” steel plate. (I thought it was iron but it’s not.) And yes, we had fires in it for 15 or more years with no problem except inefficient heating. They say the pipe (original) was triple wall because where we live I think that was code. I think the smell was the insulation. We put 3 cords of wood through this last year and the smell would get worse when the stove got hotter. My husband thought the insulation was what was smelling. Why would they have put that in there at all? Oh, and KD mentioned a wooden framed chimney to go with the zero clearance and that is what this is (masonry on the outside). And KD, this woodstove is attached to the triple wall pipe and sealed off. There is no additional liner but do we still need it if the pipe is triple walled?

The “guys” who put it in were the installers so we originally presumed the insulation was supposed to be in there. And please don’t worry about sounding sarcastic. You absolutely did not. We can’t get straight answers unless you have adequate information. This helps me to be more concise.

And “Better Safe Than Sorry” - I don’t know the manufacturer but will try to find out to see if it is compatible with the stove. What would make one woodstove compatible and not another?

You have all been very gracious to help and I’m interested in your further feedback. Thank you so much.

OregonCountry

 

[OregonCountry]

More clarification....

About the pictures.....don’t know how to do that myself and would need my husband to help there. We have a digital camera but I wouldn’t know how to drop it in to the computer and post it here. sorry… All I can tell you is that the zc is wider at the front, narrows toward the back, the woodstove sits flush against the back and juts out about 12 inches past the flush point with the zc. We can set an iron kettle on the top and could actually cook on it I guess if we were so inclined. It came out of an existing fireplace, had no legs, and has a brick lined bottom (maybe they all do, I don’t know). Does that help at all? The woodstove is a double-doored glass front.

Thanks again.

OC

 

[webbie]

OC, based on your descriptions, it does not sound like a totally safe installation - but, of course, it is impossible to remotely diagnose. Some basics:

1. ZC, prefab or factory built fireplaces all mean the same thing - fireplaces that are built of sheet metal and use double or triple wall pipe to be vented. Typical venting is up through frame (not masonry). Typical pipe size is 8" , although possibly as big as 10".

2. Some use double wall, others triple - not because of code, but because of the design of the particular fireplace. Most today use double wall, but triple wall was popular years ago. It is typical for this chimney to be made JUST FOR THAT FIREPLACE. In other words, it is not generic and cannot be used to vent anything other than the open fireplace it was designed for. This is especially true for older pre-fabs....newer ones are tested to a higher standard.

3. The ONLY inserts or wood stoves which can be used in pre-fab fireplaces are those approved for such use. This would be clearly stated in the manual. Given an older fireplace (over 10 years old), the chimney should definitely have an additional new liner to match the size of the insert pipe (usually 6").

A hot cooking area such as you mention is usually not part of an approved pre-fab insert, because such a top would produce a lot of radiant heat which could penetrate into the house framing.

The insulation bit sounds strange and dangerous. You are 100% right for being nervous - from here the thing sounds like a time bomb.....but that's just my opinion and experience!

 

[OregonCountry]

Hi Craig,

Thanks for taking an interest in this. I am trying to share this info with my husband. Would you be able to explain the difference on inserts that are approved for a zc and those that aren't? He just doesn't think this set-up, minus the insulation, is unsafe. He agrees not to use it but thinks I am overreacting. His feeling is if the zc can burn wood and the smoke and heat can go up the chimney and not cause a problem, why not the insert? I told him I thought the heat (more intense) was the issue but I am not a professional and don't know if that's absolutely correct. He doesn't think it makes sense. So any clarity you could shed on the difference between those that would be approved for zc's and those that aren't would be greatly appreciated.

I told him you don't have a dog in the fight so why wouldn't you be objective? He has not wanted me to ask a woodstove place because he feels they would just try to sell us something.

Thanks again.

OC

 

[wg_bent]

Correct me if I'm wrong here guys, but one of the reasons a zero clearance fireplace chimney doesn't have to deal with heat as much is that it's essentially cooled by the huge volume of air going up the chimney with the exhaust gasses. If you just figure out what stove you have, the whole "is it designed for a zero clearance fireplace will be over" It's a yes or no answer. Also, do you (or your husband) believe that a zero clearance can take temps of 900-1200 degrees? That's what internal temps of a wood stove are. zero clearance fireplaces are made out of sheet metal.

 

[elkimmeg]

Warren correct the heat does not stay in one place long enough to really build up it exits up a fairly large chimney. Because of this t older chimneys were not tested to 2100 degrees of a wood stove but only to 1700 and who know what this setup test standard was 15 years ago. To me this setup sounds like it deserves one of my red condemned stickers.
First of all no one can confirm it is tested to UL 127 which is the minium standard requiring 1700 degrees. The manufacture can not be identified it is damaged cracked or split. The wood stove has not been checked to see if it is listed for ZC installation No mention was mafde about flue size or hoe the stove is connected no damper plate mentioned and what's with the fiberglass insulation?
where was that positioned You can bet it is illegally installed without a permit or satisfactory inspection. Who know if clearances to combustiables are met This lady is doing the right thing questioning safety

In ooregon they have very strict stove and installation requirements and yess they require permitting and inspections.

sounds to my this setup was done on the sly skirting inspections, knowing if permits were pulled it would never pass or ever issued.

What soes you homeowners insurance company require? Ill bet they want a certificat of inspections or they can void your policy.

Iam guseeing here I do not know the facts unfortunately neither does this poor girl and her children. Is it UL approved and sound condition if so and on and on?

 

[webbie]

Warren is correct.

What you have to do is give your husband a whole bunch of arguments until he gets one.....meaning he is (for now) thinking that common sense applies to this situation - and it does not!

Here is a good example. Near us in Plymouth, MA are the homes of the original pilgrims. They have chimneys made of WOOD and mud. How can you burn wood in a chimney made of wood? It is like Warren says - the massive amount of room air (cold) going up the chimney along with the burning wood made the chimney temps lower.

Pre-fabs are similar. They are designed to have a relatively low stack temp because of air going up along with the burning wood. As another example, folks who used the wrong (other than the manufacturers specific mode) glass doors on pre-fabs often saw a house fire within a couple days of hard use.

What we are saying is that it is a carefully balanced system.

When a pre-fab is installed, it is placed into wood framing. In other words there are 2x4's in the wall a few inches above the front of the fireplace. When it is used open, it sucks so much cold air in that the front stays cool....but if you close some of the front off and vents off....well, all bets are off.

The more I think about your entire installation, the more concern I have for your life and property.

OK, the difference between pre-fab approved and not - one of them is the LACK of radiant surfaces such as you have. Pre-fab inserts are usually double wall all around and typically do not stick out much. They are actually tested within a sample fireplace like yours. They are also (in general) smaller and have less heat output - therefore less dangerous.

Given the age of your unit, you have a lot to be concerned about.

BTW, the enclosed pic from one of our users shows triple wall pipe after too many years.......might give you some idea of why another liner is needed.

Another word of caution - even if you get a permit or check with your insurance - be aware that these people often do not know a lot about pre-fabs. There have been stories here about inspectors walking in, nodding and signing off.

It's YOUR life and property. Although it it difficult to know from afar, I think the experts here will agree that you have too many problems to fix. The only real fix is to remove that unit, carefully check the fireplace and install an approved insert with a new liner.

 

[OregonCountry]

Thank you so much, all of you, for your very informative feedback. It seems crystal clear and makes so much sense. I will try to explain this to him when he is in a receptive mood. We don't have much money and this kept all of us warm last year when we could cut our own wood and couldn't afford a utility bill. Our central heat is broken most the time and only works intermittently. But, being chilly is preferable to being on fire. Hope he can hear this without being mad. I know some guys don't like to have their decisions questioned. But it saves him money (no flue cleaning) and effort (no wood cutting) if we can't use it. So hopefully that will be some comfort. For many reasons it's been a long, very hard year. Thanks for listening and thank you, thank you for your support and advice.

God bless you guys,

OC