Harman Accentra Insert Pipe Stub to ICC Adapter Questions

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padlocked17

New Member
Oct 15, 2020
18
PA
All,

As I'm fitting the generic ICC adapted to the Pipe Stub adapter, I'm a little unsure of how to attach it.

I am assuming I should sit the adapter down as far as it will go and then screw through the outer sleeve (B in the picture below) and through the pipe stub screw hole to attach it?

I'm assuming then that I will use a healthy dose of silicone both on the outside of the pipe stub and all along the space between the inner and outer liner of the adapter?

Trying to fix a poor install job done some years ago discovered after pulling out just the pipe to replace.

Thanks!

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The inside of the adapter should go on the outside of the tailpipe.
 
The inside of the adapter should go on the outside of the tailpipe.

It's not even remotely close to the right size. The top of the tailpipe measures 4.5" and the inside of the adapter measures 4". There is a rubber gasket on the inside of the adapter between the inner and outer wall and the adapter slides down placing the tailpipe between the inside and outside wall of the adapter.
 
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It's not even remotely close to the right size. The top of the tailpipe measures 4.5" and the inside of the adapter measures 4". There is a rubber gasket on the inside of the adapter between the inner and outer wall and the adapter slides down placing the tailpipe between the inside and outside wall of the adapter.

i just installed a accentra insert and had the same issue. What I was told was to let the adapter be placed as you Show in your pictures. Silicone it heavy so as you push it, it will have a firm seal. FYI... the Harman adapters that duravent make will not work or fit. Harman customer service will not give you a answer either. As for the screw, I wouldn’t worry bout it too much as your silcone will adhere the adapter to the stub. Just push the adapter until it bottoms out
 
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i just installed a accentra insert and had the same issue. What I was told was to let the adapter be placed as you Show in your pictures. Silicone it heavy so as you push it, it will have a firm seal. FYI... the Harman adapters that duravent make will not work or fit. Harman customer service will not give you a answer either. As for the screw, I wouldn’t worry bout it too much as your silcone will adhere the adapter to the stub. Just push the adapter until it bottoms out

Thats good to hear. Just looking at it and feeling the give it has, it would seem a healthy dose of RTV would do the trick, just seems like such an integral piece would have a better fit from the big name pipe manufacturers and Harman. Thanks for letting me know I’m not the only person who has run into this.
 
Thats good to hear. Just looking at it and feeling the give it has, it would seem a healthy dose of RTV would do the trick, just seems like such an integral piece would have a better fit from the big name pipe manufacturers and Harman. Thanks for letting me know I’m not the only person who has run into this.

FYI. The vertical weight of your pipe will keep the pipe and adapter in place. When I put my adapter onto the stub silcone pushed out heavily. Then I just spread it over the lap joint to create a heavy seal. I understand where your coming from on questioning the stub/adapter. You would think the design would fit better but as of right now my insert is doing fine. I did a zero clearance setup.
 
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FYI. The vertical weight of your pipe will keep the pipe and adapter in place. When I put my adapter onto the stub silcone pushed out heavily. Then I just spread it over the lap joint to create a heavy seal. I understand where your coming from on questioning the stub/adapter. You would think the design would fit better but as of right now my insert is doing fine. I did a zero clearance setup.

I’m just now getting this taken care of. As I’m sitting the adapter over the stub, it is contacting the higher portion of the stub / frame and doesn’t allow the adapter to sit level on the stub. Should I cut a notch in the inner and outer sleeve to let it sit level and then RTV it or leave it as is and just level it when I put the silicone on? Or none of the above and attach everything all at once and let the weight of the pipe above settle the adapter into place when installing?

Im trying to avoid having the weight of the pipe shift it or break the seal and also keep the pipe coming out straight from the enclosure & ZC box.
 

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Alright, I ended up cutting a notch on the adapter and then thoroughly RTV'ing the stub and exterior. Now it sits level and should have no issues with a seal. Leaves 3/4" between the bottom of the notch and the seal in the inside liner.

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The process I did was first install and secure the stove frame. Second was installation of adapter and pipe. The ceiling thimble and roof flashing helped the adapter/pipe stay plumb while silicone cured. My duravent pro adapter seemed to fit deeper onto the stub but with your notch it looks to be secured well enough and looks to be enough sealant. Put a hose clamp on it and I think your be good to go.