Can someone explain the wall thimble that combines the hole for fresh air intake?

[geek]

I am a bit confused, looking at a picture online it shows the bigger hole for the exhaust and then on the side a smaller hole for the fresh air, the purpose for this combo thimble is to be able to only cut one hole in the wall.

However, the thimble is 2 pieces, one inside and one outside and both get connected to then pass the pipe though it, so where does the smaller air intake hole go?

https://www.dynamitebuys.com/store/secure/images/products/711_large5.jpg

 

[geek]

Ok, I spoke to someone and basically it is not one hole but 2 holes, it is just that the outside plate of the thimble would look like a single piece but in the back there are 2 holes.
The blurb on the web page is misleading a bit, it reads:

"The Simpson PelletVent Pro Wall Thimble Air Intake Kit allows outside fresh air for combustion through the wall thimble without having to cut a second hole into the wall".

..

 

[imacman]

Geek, if your wondering what happens on the outside of the house, the fresh air tube gets a plastic cap over it that has either wire mesh or louvers over it to keep bugs, leaves, etc out.
Something like this:

EDIT: OK, I guess you weren't asking about the outside cap.....sorry....LOL.

I guess the advantage of the combo thimble is that you cut one hole that will fit both tubes or 2 separate holes, but they are covered by one plate on the inside and outside. IMO, it makes for a neater looking install.

 

[geek]

I guess the advantage of the combo thimble is that you cut one hole that will fit both tubes or 2 separate holes, but they are covered by one plate on the inside and outside. IMO, it makes for a neater looking install.

yeah, the advantage is only that the outside covers the 2 holes and looks better. The blurb online is misleading saying you only cut one hole, I mean you could cut one single hole but it'll be a huge one.

Thanks.

 

[Delta-T]

the wall thimble used by Harman uses just one hole to do both. The part of the thimble that penetrates the wall is square instead of round and the extra space around the pipe is used for the intake. The piece of the thimble on the insde has a small box on it and a separate flange for the intake pipe. The outside has a small grill built into it to act as a screen. It looks snappy. I'm not sure how applicable it is for non-Harman units (simply beause the size of the intake flange) but it does keep things looking a little neater than 2 holes in the wall.

 

[geek]

the wall thimble used by Harman uses just one hole to do both. The part of the thimble that penetrates the wall is square instead of round and the extra space around the pipe is used for the intake. The piece of the thimble on the insde has a small box on it and a separate flange for the intake pipe. The outside has a small grill built into it to act as a screen. It looks snappy. I'm not sure how applicable it is for non-Harman units (simply beause the size of the intake flange) but it does keep things looking a little neater than 2 holes in the wall.

would like to see a picture on the web somewhere if you can point me to so I can check it out as an option.

.

 

[pelletizer]

I made my own out of a standard thimble kit check it out,
I have apost on here somewere how to do it,

 

[smoke show]

good idea, if it meets code. wth why not?