Making a Fireplace Damper Cut-Off Plate

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Made my first video today on the iPhone. Here is how I make my fireplace damper terminations. What I forgot to mention...there is 8" of mineral wool on top of these plates.

For those who are curious...yes, that's me there doing the talking. MY GOD! I'm bald!!




 
Nice job, made many in my time, always seemed to get cut;)
 
Great job!!! And don't worry, GOD is with you my man....
 
Nice Video of damper plate with insulation.

8" of Roxul is R32 ! ! ! That keeps the cold out!

Is that what is in there?
 
Am I assuming correctly that the purpose of this block off plate is so you don't have to run the liner all the way to the top of the chimney? i.e "fireplace damper terminations" Or am I dead wrong and if so why? I had the same set up on my woodstove install prior to the pellet stove so that is sort of why I am asking.
 
Am I assuming correctly that the purpose of this block off plate is so you don't have to run the liner all the way to the top of the chimney? i.e "fireplace damper terminations" Or am I dead wrong and if so why? I had the same set up on my woodstove install prior to the pellet stove so that is sort of why I am asking.
Ah, good question. No, in fact my liner here goes all the way to the top of the chimney...about 31' up there. It was a high one. The purpose for the cut off plate is to seal off the warm air from the house and keep it from rising up into a cold chimney cavity.

Not as Don mentions...to keep out cold drafts, though it does help with that too.

What you are talking about is what we call a damper installation. They are not allowed in MA. They should be banned anyway as they are problematic on for many reasons. Very much a PITA to clean and maintain...especially when they have been neglected for 11 years or so.

Difference being, with a pellet stove, the exhaust motor drags a lot of ash from the stove into the venting and it just piles up high on the other side of the plate. Wood, not so much...though there is some.
 
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Damper installs are still allowed in CT with a 6' stainless flex kit, I do prefer and recommend all the way up sealing off at the top.
 
Hello
The metal damper seals the chimney and keeps the warm room air from rising out. I was talking about the insulation which keeps cold from convecting in thru the metal. :) Also if the insulation is fire proof it will protect the room against a chimney fire !
 
Ah, good question. No, in fact my liner here goes all the way to the top of the chimney...about 31' up there. It was a high one. The purpose for the cut off plate is to seal off the warm air from the house and keep it from rising up into a cold chimney cavity.

Not as Don mentions...to keep out cold drafts, though it does help with that too.

What you are talking about is what we call a damper installation. They are not allowed in MA. They should be banned anyway as they are problematic on for many reasons. Very much a PITA to clean and maintain...especially when they have been neglected for 11 years or so.

Difference being, with a pellet stove, the exhaust motor drags a lot of ash from the stove into the venting and it just piles up high on the other side of the plate. Wood, not so much...though there is some.

Ah, very nice explanation. That helps me a lot thanks. Looks like I will be making one of those bad boys for my insert. What about the OAK which is a different 2" line that goes to the top? Would you cut two holes in the plate?
 
i dunno...what kind of technician bends over and doesn't show some "cleavage"? You're gonna make the rest of us look bad ;lol. Nice snipper work. We use a fancy plasma cutter thingy. HIgher danger level=more danger. And who doesn't like some danger?
 
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Hello

Here is a good video on how to insulate a chimney liner with a spray adhesive. This is what Olympia Chimney was talking about. It works well for chimneys on the end of a house that are cold outside chimneys. The insulation keeps the flue gasses from cooling too quickly and the ash collecting and building up on cold spots on the inside walls that can choke the chimney down quickly in some cases. Nice extra benefit.

http://www.youtube.com/watch?NR=1&v=5OIcxRdb6Rs&feature=endscreen

 
Ah, very nice explanation. That helps me a lot thanks. Looks like I will be making one of those bad boys for my insert. What about the OAK which is a different 2" line that goes to the top? Would you cut two holes in the plate?
Yes, if the outside air is going to be taken from the chimney flue you would make another section. When I do those, I make my plate into 3 sections and take the air up the other side. If you are taking the air line up like that you also need a different type of cap. It's called a collinear cap. I use this one from Olympia. They make them in crown mount and terra-cotta mount. You have to specifiy that you want a 3" adapter for the air supply line, they come 4" and 4" for exhaust and air.
collinear-cap.jpg


http://www.olympiachimney.com/products/cat/CC/ASCC/CCCLTM
 
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Hello
The metal damper seals the chimney and keeps the warm room air from rising out. I was talking about the insulation which keeps cold from convecting in thru the metal. :) Also if the insulation is fire proof it will protect the room against a chimney fire !
You don't really know what you are talking about do you?
 
Hello

Here is a good video on how to insulate a chimney liner with a spray adhesive. This is what Olympia Chimney was talking about. It works well for chimneys on the end of a house that are cold outside chimneys. The insulation keeps the flue gasses from cooling to quickly and the ash collecting on the inside walls. Nice extra benefit.

http://www.youtube.com/watch?NR=1&v=5OIcxRdb6Rs&feature=endscreen


I understand...but once again you are displaying a wood stove liner and not a pellet liner. You are displaying what is needed for a natural drafting wood stove liner. THIS IS THE PELLET FORUM DUDE!
 
I understand...but once again you are displaying a wood stove liner and not a pellet liner. You are displaying what is needed for a natural drafting wood stove liner. THIS IS THE PELLET FORUM DUDE!

Olympia liners work for wood and wood pellet stoves, boilers etc. Chimneys are different, center chimney, outside chimney. Olympia talks about the right liner for the type of chimney not the appliance!
 
You don't really know what you are talking about do you?

The metal damper and caulking seals the chimney and keeps the warm room air from rising out. I was talking about the insulation added above the damper which keeps cold from convecting in thru the metal. :) Also if the insulation is fire proof it will protect the room against a chimney fire !

I am not saying anything was done wrong, just helping to provide more info so the best choices can always be made.

Then if this is not the case, you explain it better?
 
Olympia liners work for wood and wood pellet stoves, boilers etc. Chimneys are different, center chimney, outside chimney. Olympia talks about the right liner for the type of chimney not the appliance! You are stuck on just pellet stoves!
I am stuck on pellet stoves because this is the pellet forum;) and the name of my company is pellet stove service.!!!
The metal damper and caulking seals the chimney and keeps the warm room air from rising out. I was talking about the insulation which keeps cold from convecting in thru the metal. :) Also if the insulation is fire proof it will protect the room against a chimney fire

The purpose for the damper plate:
  1. To keep warm air from rising up in to the chimney. Warm air contains moisture. The moisture will condense in to chimney and be absorbed by the masonry. When temps fall below freezing the water in the masonry will expand and over time the chimney will start to fall apart.
  2. If you have a multi-flue chimney, such as the case with this install, if the OTHER chimney flue ever had a fire....the flue we are in could supply air to that fire.
  3. I suppose insulating the chimney damper can keep out cold drafts...but there is presumably a stove in the opening which is on and thus cold air isn't going to be felt. The flue is also capped at the top so we aren't talking about air rushing down the flue.
Insulating the liner...with pellet liners it is not required and would not really contribute to the drafting. Wood stoves or should I say, NATURAL drafting appliances...and there are pellet stoves that utilize natural draft, would and do benefit from insulated liners. I'm not the be all end all when it comes to this type of work but you are confusing people by showing the installation of a 6" wood stove liner. FYI I didn't see those guys install a damper plate on that Jotul.
 
Hello

From the Pro liner venting catalog:

Why and When to insulate the chimney liner:

click to enlarge:

c:\pellettesting\venting\LinerInsulation

 

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Hello

From the Pro liner venting catalog:

Why and When to insulate the chimney liner:

click to enlarge:

c:\pellettesting\venting\LinerInsulation
We could go back and forth forever. If you want to wrap your pellet liners, there isn't really a downside. Knock yourself out. Is it really needed? No. Will it hurt? No. Will there be any problems if you don't? No.

If you do not agree, find some liners not insulated and show us evidence. I'm willing to bet I have installed more inserts alone than stoves you have looked at seen or worked on. I go back to these inserts year after year after year and there is NO evidence of creosote whatsoever anywhere in the liner. We are talking hundreds of inserts a year man....if there was going to be a problem I would have seen it by now.

But then again you may be just the man for the job. Like I said, knock yourself out.
 
I agree. The chimney suppliers are always trying to sell more stuff.
 
I will toss it out there though..there are situations where insulating the liner is needed.

If I am installing a liner on an outside facing chimney that is higher than 45 feet...I will insulate.
If I am installing in a chimney that does not have a clay lining in the flue...I will insulate.
If I am installing in a chimney with an off-set...I will insulate.
If I am installing in a chimney where the clay flue tile is damaged or missing in sections...I will insulate.

The first is a performance issue, the rest are safety issues.

Maybe 1 in a hundred installations fall in to these categories.

DONE with this thread unless there is something new to add:)
 
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