Missing stovepipe screws?

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thunderhead

Burning Hunk
Oct 18, 2019
122
Seattle - Eastside Foothills
So during our first cleaning(stove was installed last Jan), I noticed... our double-wall stove pipe has no screws where the bottom of the stovepipe meets the stovetop collar. It just sits there, held in place by gravity. Up top, where the uppermost 30 degree elbow meets the ceiling support box, there is just 1 screw installed there. Is that OK? Where the stovepipe meets the elbows, and each of the extendible segments, is secured in place with sets of 3 screws. So the stove pipe can't really move in normal operation, and it is pretty hard to get in and out even when I take those sets of 3 screws out. But I am worried about what happens if there is ever an earthquake while the stove is running or something like that.


Our install(from top down, ceiling support, 30 degree elbow, telescoping double wall stove pipe, 30 degree elbow, telescoping pipe, stove):
[Hearth.com] Missing stovepipe screws?

Thanks!!
 
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I've seen a lot of people go without screws in the stove collar....I dont know why because they are cheap and it seems like good practice. I would screw off every joint personally....especially if I lived in a earthquake prone area.
 
There should be 3 screws per joint. It's not just for earthquakes, but also if something causes a large puffback or something inadvertently bangs into the pipe.
 
If this was just installed, they are required to install those screws. They come with the pipe. The installer should be called back to do this.
 
Everyone is telling you it should have 3 screws at the flue collar, but it’s usually not that simple. The stove pipe manufacturer offers a stove pipe adaptor that doesn’t have any way to attach it to the flue collar without other parts or modifications. The average person won’t know this or have the ability.
I never understood how they can require 3 screws on every joint, prepunched, screws provided, but completely ignore the part about attaching it to the stove.
 
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Everyone is telling you it should have 3 screws at the flue collar, but it’s usually not that simple. The stove pipe manufacturer offers a stove pipe adaptor that doesn’t have any way to attach it to the flue collar without other parts or modifications. The average person won’t know this or have the ability.
I never understood how they can require 3 screws on every joint, prepunched, screws provided, but completely ignore the part about attaching it to the stove.
Me neither. Fishers always came with one hole in the collar. I’ve had pipe that wouldn’t round out to seal in the collar as well, and added more to pull the pipe out to the collar for a precision fit.
 
I usually have had to drill new holes in the flue collar to match the pipe holes.
 
I usually have had to drill new holes in the flue collar to match the pipe holes.
We aren’t going to be drilling holes in new stoves. There’s a few other ways to accomplish a secure connection.
 
We aren’t going to be drilling holes in new stoves. There’s a few other ways to accomplish a secure connection.
In the flue collar? Why not? What do you do as an alternative?
 
In the flue collar? Why not? What do you do as an alternative?
Gorilla glue?????

Screwed and elbows have high temp silicone applied.
 
In the flue collar? Why not? What do you do as an alternative?
Drilling holes in a stove will void any warranty and violates any UL listings. Same as drilling additional holes in the double wall pipe to allow a positive connection. I’ve posted the solution to this problem in the past and was torn apart for it. Won’t post it again...
 
How would this void UL listings or warranty? It's certainly not going to change the tested results for the stove. Have you been told this by the stove mfgs.? If so what stove company(s)?
Sorry if this is digging up old stuff. I don't recall that old thread at all, but it sounds like I missed it. Wouldn't be the first time. The solution is important for those looking for it. Can you post a link to the old thread?
 
Drilling holes in a stove will void any warranty and violates any UL listings. Same as drilling additional holes in the double wall pipe to allow a positive connection. I’ve posted the solution to this problem in the past and was torn apart for it. Won’t post it again...
Does any stove manufacturer allow additional holes to be drilled in their stove?
 
That's answering a question with a question, but honestly, I have never read - Don't drill holes in the flue collar. To do so will void warranty - in any of the hundreds of stove manuals I have read. SBI stoves clearly state:
One end of the assembly must be securely fastened to the flue collar with 3 sheet metal screws and the other end securely fastened to the chimney.
PE inserts state that one must screw in fasteners to the liner adapter to secure. How else would one do this?
 
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That's answering a question with a question, but honestly, I have never read - Don't drill holes in the flue collar. To do so will void warranty - in any of the hundreds of stove manuals I have read. SBI stoves clearly state:
One end of the assembly must be securely fastened to the flue collar with 3 sheet metal screws and the other end securely fastened to the chimney.
PE inserts state that one must screw in fasteners to the liner adapter to secure. How else would one do this?
No manufacturer will tell you It’s ok to drill new holes in the flue collar. It doesn’t matter anyway. I’m not aware of any quality stove being made that doesn’t have 3 holes in the flue collar, except Jotul. They only have 2 holes.
Often times it takes some creativity to make the connection. It’s unfortunate that the stove and pipe manufacturers leave the installer hangin.
 
What about from the pipe to the ceiling support? That should have 3 screws too, right?


Edit: Just phoned the installer... they did miss 2 screws up top that are supposed to be there.

They said they prefer to allow the bottom end to just sit on the stove's flue collar, to allow for some expansion/contraction under heating.
 
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What about from the pipe to the ceiling support? That should have 3 screws too, right?


Edit: Just phoned the installer... they did miss 2 screws up top that are supposed to be there.

They said they prefer to allow the bottom end to just sit on the stove's flue collar, to allow for some expansion/contraction under heating.
The telescoping section handles expansion.
 
Does any stove manufacturer allow additional holes to be drilled in their stove?
I never gave this a thought, but wanted to be sure so I contacted 4 major companies to find out, two Canadian and two US. So far 2 have gotten back to me saying it's ok to drill into the flue collar.
 
I never gave this a thought, but wanted to be sure so I contacted 4 major companies to find out, two Canadian and two US. So far 2 have gotten back to me saying it's ok to drill into the flue collar.
Have at it then. Like I said, it’s not necessary on current models. Nor would we ever been drilling holes in a new stove.
 
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Have at it then. Like I said, it’s not necessary on current models. Nor would we ever been drilling holes in a new stove.

I remember your old trick but not the complaints from the complainypants contrarians. If somebody decided I needed to screw the double wall to my stove then I would certainly try to replicate your procedure instead of the alternatives which really don't exist or are hacks.

Now for single wall pipe it's easy. And to agree with BeGreen I would drill holes in the stove collar if none were predrilled from the factory.
 
My chimney guy never screws to flue collar either.on double wall pipe
 
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I remember your old trick but not the complaints from the complainypants contrarians. If somebody decided I needed to screw the double wall to my stove then I would certainly try to replicate your procedure instead of the alternatives which really don't exist or are hacks.

Now for single wall pipe it's easy. And to agree with BeGreen I would drill holes in the stove collar if none were predrilled from the factory.
Yes. In a perfect world, double wall stove pipe screw holes would always match the flue collar, but they don't. Sometimes you want to set the pipe deeper in the collar and they don't align. Sometimes the flue collar only has one or two holes. If one is taking a 45 off the collar, who is to say at what exact direction it will be pointing? The alternative is to drill out the customer's new stove pipe in order to try to align with the flue collar holes, leaving the factory holes as extras which some may view as slightly unsightly.
 
Yes. In a perfect world, double wall stove pipe screw holes would always match the flue collar, but they don't. Sometimes you want to set the pipe deeper in the collar and they don't align. Sometimes the flue collar only has one or two holes. If one is taking a 45 off the collar, who is to say at what exact direction it will be pointing? The alternative is to drill out the customer's new stove pipe in order to try to align with the flue collar holes, leaving the factory holes as extras which some may view as slightly unsightly.

What I think would solve this more correctly is that the inner wall of the double wall appliance adapter should be longer so that the outer shell is out of the way far enough to access the predrilled screw holes in the stove collar. Then you have access to install screws just as with single wall pipe wherever they are needed. Then you drop on the first piece of stove pipe and use all normal connection methods between sections of double wall. I suppose an installer could trim that outer shell of the appliance adapter to accomplish this. Some folks get all worried about the thin sliver of single wall flue that would then be exposed but I think that is silly.
 
On our stove with a 45 right off the collar, I measured carefully and drilled the fitting instead of the flue collar. None of the factory holes in the 45 matched the stove hole locations.