Do Dealers/installers normally put in block off plates?

[daveswoodhauler]

Ok folks, so my Lopi Answer Insert was removed today to go back to the dealer for some welding and repairs.
Anyway, when I came home the stove was gone, and when I looked up the chimney to check out the liner, it looked really clean...so thats good.
One thing I was surprised to see was that there was no block off plate installed.
So, I guess this was a newbie mistake not making sure that the installer put one in when they installed the Insert.
Is this something that should have been put in? Or was I to ask for one to be put in specifically from the dealer? (I can take a ribbing from the experts here)
Basically, it seem to be a safety issue, as well as efficiency...as without the plate you will have more warm air going up the chimney i.e. heat loss.

Anyway, since the insert is out, and I have the time, I can probably construct one....just don't know where to start.
Thanks.

 

[daveswoodhauler]

Yup, that what I was thinking...already got the cardboard out.
Just not sure what to make it out of....i.e. what type of steel. (I really don't have a clue when it comes to metal)

 

[BrotherBart]

I don't know that 1 in 1000 installers install block-off plates with inserts. And I am the bad buy around here that agrees with them but that is another story.

In the duct work section of Lowe's thay have a piece of galvanized sheet metal for seven or eight bucks that is perfect for the job.

 

[Wood Heat Stoves]

i dont think it matters & i'd use aluminum for its reflective & anti corrosion properties= guessing

any component that cant be visually inspected should be stainless like the liner!!

24ga ss sheetmetal is what we use.

i know of no code or stove maker "requiring" a plate.......but they cant hurt to help create dead air space.

 

[Michael6268]

Weve gone round and round on this many many times but the truth of the matter is, if you have a properly installed/sealed off top plate with a liner, there is no need for a damper block off plate. As far as heat loss, it would be minimal because it would have no where to go. (i suppose one could say the cool masonry up in the chimney might absorb some of the heated air) Furthermore, the heated air actually helps warm your liner thus aiding in the draft.

 

[Wood Heat Stoves]

i dont think it matters & i'd use aluminum for its reflective & anti corrosion properties= guessing

any component that cant be visually inspected should be stainless like the liner!!

24ga ss sheetmetal is what we use.

i know of no code or stove maker "requiring" a plate.......but they cant hurt to help create dead air space.

aluminum melts @ 1200*f i think so why not?

and a chimney fire is what temp??!!2100 ish
aluminum is ok for gas appliances, not wood

use stainless

 

[BrotherBart]

Yeah and steel melts at 2,300 but I don't know of any stainless steel stoves out there, or stainless steel shrouds on inserts either which are a hell of a lot closer to the fire than a block off plate. A galvanized block-off plate is just fine. It isn't in contact with the stove and the direct contact with the liner is less than a few bazzillionths of an inch thick.

Selling your customer a stainless steel block-off plate should be a misdemeanor.

 

[Wood Heat Stoves]

^^^^^^^^^^^^^^^^^^^^^^^
good quality liner kits like homesaver come with/ have the option of stainless steel block off plate. imo there is a reason, but i agree galvanized is probably fine>the only issue if it does get over 1200 it off gasses some really bad stuff(carcinogenic)

selling your customers on the proper products based on solid industry knowledge isn't a crime man, its the right thing to do. give them an option for sub-par materials, but have the proper info to offer too!

true, no stainless woodstoves, but when do you have a chimney fire in your stove? stove temps will Never get as hot as a chimney fire.

 

[Wood Heat Stoves]

Yeah and steel melts at 2,300 but I don't know of any stainless steel stoves out there, or stainless steel shrouds on inserts either which are a hell of a lot closer to the fire than a block off plate. A galvanized block-off plate is just fine. It isn't in contact with the stove and the direct contact with the liner is less than a few bazzillionths of an inch thick.

Selling your customer a stainless steel block-off plate should be a misdemeanor.

4 sq ft Stainless steel sheet metal $6.95 $27.80

here is what i charge, criminal?

 

[Todd]

All the shops around here say it's not needed but some will fill that gap with kaowool/rockwool insulation.

 

[BrotherBart]

...but when do you have a chimney fire in your stove? stove temps will Never get as hot as a chimney fire.

And neither will a block off plate. That be the point. In fact single wall mild steel connector pipe hasn't melted in any chimney fires I have ever heard of. Gets a little noisy, but doesn't melt. And it has the actual chimney fire burning inside of it.

Mild steel block off plates are tested and accepted with every manufacturer's direct connections. No reason not to use them with full liners.

 

[Wood Heat Stoves]

...but when do you have a chimney fire in your stove? stove temps will Never get as hot as a chimney fire.

And neither will a block off plate. That be the point. In fact single wall mild steel connector pipe hasn't melted in any chimney fires I have ever heard of. Gets a little noisy, but doesn't melt. And it has the actual chimney fire burning inside of it.

Mild steel block off plates are tested and accepted with every manufacturer's direct connections. No reason not to use them with full liners.

carbon steel is a better option for materials directly in contact with single wall liner than galvanized. i just dont see the piont in saving 10-15$ on an installation that will/should outlast the home.

cera blanket sure is easier! as someone who has installed liners for 10+ years, any short cut that works is ok with me, but plates are better imo

 

[Highbeam]

I propose that you can't possibly lose heat to the chimney space so long as the proper top block off plate is installed. Really now, within that chimney lies the flex liner that is cooking along at several hundred degrees heating the airspace between the liner and the chimney tiles. The air in that space will be much hotter (less dense) than the air in your home so the more dense home air will not be able to displace the hot air.

I would be more conerned with the stink or mess during the summer.

I certainly can't think of a safety issue with it.

Oh and if a lame installer only puts liner in to the damper plate, say 4 feet, then I would insist on the damper block off plate.

 

[Michael6268]

.[/quote] warm air up the chimli carries humidity which will condense on cold surfaces & if it freezes...? i know that ice expands via such ass frostheave[/quote]
Really makes no sense. Even with a block off plate you are still going to have warm air up there. (actually more due to fact that it is now trapped in there between the bottom and top block off plates)

 

[jtp10181]

Original questions was... "Do Dealers/installers normally put in block off plates?"

Where I work... No
Out of my 5 years being there I have had 2 customers inquire about them.

Are they required by code? Not locally, and not by any national code I know of. All codes I have seen state the flue must be sealed either top or bottom. We seal at the top with the top plate supplied with the liner.

If a customer asked would we install one? First of all the previewer would probably talk them out of it... why... I don't know, that's just what he does with extra things like that most people think are useless. If they still insisted we would put one in for an additional charge.