If the chimney is sealed at the top, around the liner, is a block off plate still needed for my insert?
No Block Off Plate - Is That OK?
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STOVEGUY11
Feeling the Heat
Assuming everything else is installed correctly, I think you will be OK....unless there happens to be a chimney fire, then things might get a bit touchy. Admittedly, I've burned my stove like that for a couple of years. It's kind of like not havnig a fire extinguisher in the kitchen....it's perfectly fine to not have one...udoesn't affect the taste of your cooking. But then when you need it, suddenly you really, really wish you had one.
its safer to have one... and it keeps heat from leaching up and out... and drafts and all.
just make one... template out of cardboard first, then cut sheet metal.
just make one... template out of cardboard first, then cut sheet metal.
Yeah...I'm thinking that when I have chimney cleaned for the first time, I'll put one in at that point. Thanks, I feel a little bit better about things now and can't wait to do that first break-in first tonight.
I don't have a block off plate for my insert (exterior brick chimney). The dealer said it was not necessary (or maybe he didn't want to take the time and effort to make and install one for me). This has always made me concerned about what difference there would be with or without one.
A SS liner was installed from the stove, running to the top/opening of the chimney, then the chimney cap is affixed to the last terracotta tile protruding from the last course of bricks. The liner comes right to the bottom of the cap, so the inside of the chimney is never exposed to smoke and creosote.
I can see there being a loss of heat from the insert to the area between the liner and the inside of the chimney, but other than that, I'm not sure of any other issue this presents. If anything, it warms the masonry surrounding the liner.
Can anyone shed any light on this? The two of us can't be the only people without block off plates above our inserts.
A SS liner was installed from the stove, running to the top/opening of the chimney, then the chimney cap is affixed to the last terracotta tile protruding from the last course of bricks. The liner comes right to the bottom of the cap, so the inside of the chimney is never exposed to smoke and creosote.
I can see there being a loss of heat from the insert to the area between the liner and the inside of the chimney, but other than that, I'm not sure of any other issue this presents. If anything, it warms the masonry surrounding the liner.
Can anyone shed any light on this? The two of us can't be the only people without block off plates above our inserts.
That's what I'm thinking too - that I'll be losing some heat. But this will be my first season with it, so we'll see how it goes. Still, just for peace of mind, I'll probably install a block off plate when I arrange for the first cleaning.
I'd like to make one myself and put it up there. It's just a PITA getting the 3 piece surround panel that goes over/around the insert back together again. This needs to be removed every time to sweep the liner because there is a 90 degree adaptor that is attached to the flue collar, then on to the liner, so the soot can't just go down into the fire box, it collects in the adaptor. The adaptor has a little access door on it to get out the debris from sweeping. Nifty device, it's adjustable and telescopic, and the door is held closed by two wing nuts, but all of it makes me wish I could clean the unit without so much effort.
They had to add this to make the bend from the flue collar to the liner without crimping the liner. Has anyone else had to have one of these used in their insert install?
They had to add this to make the bend from the flue collar to the liner without crimping the liner. Has anyone else had to have one of these used in their insert install?
fredarm
Minister of Fire
My insert doesn't have a block-off plate either. Just like Chardler's, my dealer said it wasn't necessary. I have an exterior chimney with a full SS liner, and chimney cap. The surround is tight to the brick. My sense (and hope) is that the heat loss will be fairly minimal. My fireplace is small and the insert is a tight fit, so I don't think I'll be retrofitting a block-off plate. Maybe I'll ask the sweep about it when I get it cleaned.
We hear this pretty frequently. And in effect, the installers are often correct, it's not needed. But then again, they're not paying for the wood you burn. Often, what they are really saying is - too much work, or that they aren't very good at working with sheetmetal. Instead they do nothing or just stuff insulation around the liner and call it good. Not!
Personally, I'd rather that my hard work and wood went toward heating the house. A lot of heat can rise off the back of an insert. Without a block-off plate, that may be wasted to the outdoors by letting it warm up the whole stack. How much? This would be a great thing for some folks to use their IR thermometers for! We've seen cases here on Hearth.com where folks complain that their stove can't heat the house. They put in a block-off plate and suddenly the stove is doing what they expected of it. So, for those that don't have block off plates and insulated liners in their external chimneys, measure the exterior brick temp after the insert has been burning all day. Then decide whether you need a block-off plate. Basically it's a question of whether you want to heat outdoors or your house.
Personally, I'd rather that my hard work and wood went toward heating the house. A lot of heat can rise off the back of an insert. Without a block-off plate, that may be wasted to the outdoors by letting it warm up the whole stack. How much? This would be a great thing for some folks to use their IR thermometers for! We've seen cases here on Hearth.com where folks complain that their stove can't heat the house. They put in a block-off plate and suddenly the stove is doing what they expected of it. So, for those that don't have block off plates and insulated liners in their external chimneys, measure the exterior brick temp after the insert has been burning all day. Then decide whether you need a block-off plate. Basically it's a question of whether you want to heat outdoors or your house.
stanleyjohn
Minister of Fire
Im no expert!but one possible plus for having no blockoff plate is that the ss liner will be kept warmer causeing less creosote build-up.
If it was an interior chimney, that would be ok, but an exterior chimney wants to give that heat away. The colder it gets, the more you want that heat. But the more your chimney wants to give it away. Your chimney is very generous with your money.Chardler said:
RedRanger
New Member
Jags said:
Here is a good reason. When I went to bed last night the rec-room 15x26 was 88F. I really don`t want it any hotter than that. Exterior chimney,full liner and chimney cap, no block off plate. "And no, I wasn`t running the bear wide open last evening"..
Oh, and the temp outside was 37F.
buckeye
New Member
- Apr 4, 2007
- 83
My installer too said that I didn't need a block off plate. After reading everyones comments, I am going to make one. The worst part is that I have a Hearthstone Heritage and that is a heavy stove to pull out and get into the chimney. Also, is there a disconnect where the ss liner hooks to the stove? Will that have screws I assume? will it be cemented as well? There should be enough ss liner to pull the stove out right?
I dont have one either and I live in shorts and a T shirt all winter. That being said I plan on making one someday. i just have to figure out how to get the surround off.
iceman
Minister of Fire
i hope that you guys without the block off plates at least have the liner insulated (unless its interior)
then you should stuff the bottom (damper opening) with kaowool or something
then you should stuff the bottom (damper opening) with kaowool or something
sonnyinbc said:Jags said:
Here is a good reason. When I went to bed last night the rec-room 15x26 was 88F. I really don`t want it any hotter than that. Exterior chimney,full liner and chimney cap, no block off plate. "And no, I wasn`t running the bear wide open last evening"..
Oh, and the temp outside was 37F.
Is your chimney facing southeast sonny? That might explain the warming trend today. ;-)
I think the key word is need. I've talked with two sweeps and two installers in the past few months - none wanted to do blockoffs. I think because it's optional as far as code goes, and is a custom job for each install, there is little interest. My impression is that guys give a quote for a liner install and are looking to get it done asap, one shot. If they're trying to put in the stove/insert and also have a block off ready at the same time, and things are a bit off with whatever offset the liner and insert has, you could be talking about a return trip to the job site. Heaven forbid.buckeye said:
I would think a good installer could turn a nice profit by proposing block-offs: give your basic, competitive estimate and then, on top of that, give the pros and cons (=cost) of doing a block off plate. Inform the customer, let him decide, and make some money.
MrGriz
New Member
While it's not absolutely necessary to the operation of your insert (stove), I think it's a good idea.
Aside from the heat loss that has been mentioned, a block off plate also prevents flue gasses from backing up and entering the living space. Granted, if the liner doesn't fail that shouldn't be an issue. Just like if the house doesn't start on fire you shouldn't need that extinguisher and the smoke detectors.
Aside from the heat loss that has been mentioned, a block off plate also prevents flue gasses from backing up and entering the living space. Granted, if the liner doesn't fail that shouldn't be an issue. Just like if the house doesn't start on fire you shouldn't need that extinguisher and the smoke detectors.
woodzilla
New Member
iceman said:
Right on iceman. 50 bucks off of eBay and you have an instant soft block off plate. With enough left to insulate around insert or seal surround panels. Or share with fellow wood burner. Works great!
iceman
Minister of Fire
woodzilla said:
thank you ... thank you..
but remeber ICE DOES have a block off plate...
https://www.hearth.com/econtent/index.php/forums/viewthread/11697/
Jerry_NJ
Minister of Fire
My new Quad insert doesn't have a block off plate, but I can say neither did my old "slammer" ... and it heated the house well. I expect the new insert with a SS liner and cap at the top to do a lot better. This I will have to learn by experience.
Still, the block off plate seems worth considering, but as "handy" as I am I don't even have a set of tin-snips. What's needed to make a block off plate out of sheet metal, and where do you buy the sheet metal? Then, woodzilla, what are you talking about "off eBay"? Is there some kink of insulation one can just stuff in around the liner "neck" where it passes into the chimney (the smoke shelf area)?
Still, the block off plate seems worth considering, but as "handy" as I am I don't even have a set of tin-snips. What's needed to make a block off plate out of sheet metal, and where do you buy the sheet metal? Then, woodzilla, what are you talking about "off eBay"? Is there some kink of insulation one can just stuff in around the liner "neck" where it passes into the chimney (the smoke shelf area)?
stanleyjohn
Minister of Fire
Jerry_NJ said:
Jerry! When my insert was installed they stuffed the sides with fireproof fiberglass insulation.Some say there may be a smell from it or it may fall out but so far it has worked great for me.I hope your doggie is doing better! Stan
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