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Re: What is max service temperature of GE Silicone II sealant caulking?

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hr(bob) hofmann@att.net

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Nov 7, 2010, 11:16:33 AM11/7/10
to
On Nov 7, 8:17 am, Sum Guy <S...@Guy.com> wrote:
> DanG top-poasted and unnecessarily full-quoted:
>
> > Pure silicone is not good about staying stuck to materials for the
> > long haul.  You would be better served to look into hard cast duct
> > sealant.
>
> I doubt that consumer-grade sealants are pure silicone.  And besides,
> the tub and bath and exterior door and window sealant product seem to
> stick pretty well for the long haul.
>
> Again, all I want to know is the max temperature that GE Silicone II
> (door and window) can be continuously exposed to without breaking down,
> running or coming off.

Have you called GE? Look on their web site or look on the tube of
silicone, there is usually some number to call.

dpb

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Nov 7, 2010, 11:46:42 AM11/7/10
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Sum Guy wrote:
...

> Again, all I want to know is the max temperature that GE Silicone II
> (door and window) can be continuously exposed to without breaking down,
> running or coming off.

As you've been told multiple times, go to the GE web site and look up
the technical product data sheet for the specific material of interest.

If it isn't listed as suitable for the application, I'm sure GE will
have a high temperature product that would be.

You're really not trying here...

--

Sum Guy

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Nov 7, 2010, 12:32:27 PM11/7/10
to
dpb wrote:

> > Again, all I want to know is the max temperature that GE
> > Silicone II (door and window) can be continuously exposed
> > to without breaking down, running or coming off.
>
> As you've been told multiple times, go to the GE web site and
> look up the technical product data sheet for the specific material
> of interest.

I've looked there, and if they've posted those specs - I can't find
them.

> You're really not trying here...

I'm asking on the off chance someone here knows where the spec sheet
(not msds) for GE Silicone II might be found, or who otherwise might
already know the answer about max service temperature, or who might have
used it for a high temperature application (and by high temperature, I
don't mean 1000 f. More like 100 C to 200 C (200f to 400f).

If the fuckers at Home Depot carried a silicone calk labelled as
"high-temp" or if the fuckers at GE actually listed the max service
temperature on their fucking products then this thread wouldn't exist.

Evan

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Nov 7, 2010, 12:50:58 PM11/7/10
to
On Nov 7, 8:28 am, Sum Guy <S...@Guy.com> wrote:
> Evan wrote:
> > > It's not the ductwork that I want to seal.  It's more like the
> > > furnace itself, where the plenum meets the furnace, even some
> > > places inside the furnace cabinet, places that run close to
> > > some very hot surfaces, places where it would be hard to get
> > > a trowel into, places where a nozzle could easily reach and
> > > inject material.
>
> > "Places inside the furnace"  which probably have no business
> > being "sealed up" as they were not sealed at the factory...
>
> It's a 30-year-old furnace.  Lots of slop in how things fit in some
> places.  Rust in other places have opened up some seams.  
>
> > You do realize that even if you use mastic to seal the joints and
> > seams in your duct work that mastic would have to be reapplied
> > every time someone opens up those ducts to do service...
>
> Hey, I'm not the one advocating mastic.  But then again, I don't think
> that ducts need to be opened up very often to do servicing...
>
> > Why do you feel the need to make your furnace unit more difficult
> > to take apart by adding silicone caulking to it in areas where
> > it doesn't need to have it applied...
>
> When there is air blowing through or being sucked through seams, I think
> that's a good indication that it probably shouldn't happen.  Like when
> heated air is escaping through seams where the ductwork is connected to
> the furnace.  These are seams that are really never taken apart as part
> of normal servicing.  And if they ever are taken apart, it's probably to
> replace something pretty substantial (like the entire furnace).  It's
> not like I'm going to silicone seal any service doors or panels
> (hmmm...)
>
> > The goal is to seal the duct work to prevent conditioned air
> > (whether heated or cooled) from leaking out into unconditioned
> > spaces whether that be your basement or attic...
>
> And it's also to seal the ducts and passages that pull return air into
> the furnace, to prevent the furnace fan from creating a negative air
> pressure around the furnace that would lead to air being pulled down
> from the flue and creating a reverse air flow in the burner chamber that
> cause combustion flames to leap out of the combustion area and into the
> area where the thermostat and gas valves are located, and heating and
> melting any wiring in that area.
>
> > Attempting to apply sealant onto parts of the furnace unit where
> > the heated or cooled air are not exposed to is a foolhardy
> > endeavor which will not result in any energy savings whatsoever..
>
> Inside the furnace itself is where you will find places where
> conditioned air can escape and where incoming return air passages are
> not contained against leakage.  
>
> > Using silicone caulking on duct work
>
> Again, it's not the ductwork (distribution runs) that I want to seal
> with caulking.  It's basicically any of the ductwork in the furnace room
> itself, of which there is not really any ductwork as much as the main
> distribution and collection plenums or manifolds, air-filter enclosure,
> where those structures tie into the furnace, and even some places on or
> in the furnace enclosure.  
>
> > seems to be silly since there is another product which is used
> > by competent professionals for the one of the situations you
> > wish to apply the silicone caulking to...
>
> Again, that material might be fine and appropriate to apply during
> initial ductwork fabrication and installation.  It is not the
> appropriate product to use for the situation I'm describing.
>
> >http://www.alpinehomeair.com/viewproduct.cfm?productID=453059205
>
> > Is what you need to find...
>
> Interesting item listed in it's specifications:
>
> http://www.alpinehomeair.com/_viewresource.cfm/ID/1363/p/Thermal%20Ma...
>
> --------------
> Odor: Will not contaminate sweet butter
> --------------
>
> I'll remember that next time I have some sweet butter nearby.
>
> Doesn't really say anywhere if it's hard or flexible when cured.


It is quite clear that you are one of the nit-wit engineer type
homeowners that gets hung up on specs and shit that no one
in real life gives a shit about...

The only part of your "furnace" that needs to be air tight in
the manner in which you speak of is the portion where the
plenum enters and the heat exchanger is located...

You NEED NOT seal the rest of the furnace air tight as
only the plenum (where the circulation fan is) and heat
exchanger which are part of the duct work need to be
sealed...

Again, if your furnace is that far gone that air comes out
of it "all over the place" then it has other issues...

If you seal it up so tightly like you are seeking to do,
it will no longer be able to draft air for combustion
and will cease working...

As far as the "the main distribution [trunk] and
collection [return air] plenums or manifolds,
air-filter enclosure, where those structures tie into
the furnace" that is all, umm what do you call it,
DUCT WORK...

Mastic is used by home energy auditors to seal
up leaky seams in existing duct work to improve
air flow (pressure) in the duct work and reduce
the losses of conditioned air escaping the ducts
through other than the intended air registers...

Apparently you have not the first clue of what
you are doing, nor what is actually important
here and seem fixated on performing a totally
unneeded and misguided repair to make your
furnace "look" better...

If you have any further need for the specs on
how whatever GE Silicone II product or whatever
will perform, call GE and ask for it if you can not
locate such information on the internet...

~~ Evan

Evan

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Nov 7, 2010, 12:54:46 PM11/7/10
to
On Nov 7, 8:28 am, Sum Guy <S...@Guy.com> wrote:
> Evan wrote:
> > You do realize that even if you use mastic to seal the joints and
> > seams in your duct work that mastic would have to be reapplied
> > every time someone opens up those ducts to do service...
>
> Hey, I'm not the one advocating mastic.  But then again, I don't think
> that ducts need to be opened up very often to do servicing...


ROFL...

I guess that you don't have a central AC unit anywhere in that duct
work at all... Those need to be opened up at least annually to have
the cooling coil in the plenum duct vacuumed and washed clean...

But hey, you sound like one of those guys who thinks that as long
as you keep changing the filters every so often you are getting all
of the dirty and crap out of your duct work...

Lol...

~~ Evan

Sum Guy

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Nov 7, 2010, 1:17:44 PM11/7/10
to
Evan unnecessarily full-quoted:

> It is quite clear that you are one of the nit-wit engineer type
> homeowners that gets hung up on specs and shit that no one
> in real life gives a shit about...

It's usually the case that "specs and shit" are some-what important when
it comes to how things operate, and for how long, and for how well.

> The only part of your "furnace" that needs to be air tight in
> the manner in which you speak of is the portion where the
> plenum enters and the heat exchanger is located...

Any box, duct or chamber that generates or experiences a negative or
positive pressure should be air tight.

> You NEED NOT seal the rest of the furnace air tight as
> only the plenum (where the circulation fan is) and heat
> exchanger which are part of the duct work need to be
> sealed...

bla bla bla.

Any box, duct or chamber that generates or experiences a negative or
positive pressure should be air tight.



> If you seal it up so tightly like you are seeking to do,
> it will no longer be able to draft air for combustion
> and will cease working...

The furnace room is supplied with a dedicated out-door air supply duct.
The return air ducting, plenum and fan chamber should not be able to
draw air from this combustion supply duct, because if it does then it
means a negative pressure is being created in the furnace room by the
furnace fan, and this negative pressure must relieve itself by drawing
air not only from the combustion supply duct but also the combustion
flue or stack. In my case, the flue stack is not a sealed system with
respect to the furnace and the furnace room, so a negative pressure in
the furnace room will lead to air being drawn down from the flue (and
the combustion air supply duct) into the furnace room and into the leaks
on the return-air side of the fan. Naturally, any reverse air flow in
the flue is not a good thing.



> Apparently you have not the first clue of what you are doing,

We all agree that sealing holes where air is leaking into or leaking
out-of makes the system more efficient, and even more safe to operate.

I just want to use a silicone-based caulk, and you and a few others are
going ape-shit over this mastic, even though I've said that the mastic
is too cumbersome to apply in small or tight spaces, and I don't know if
it dries hard or flexible (I would want flexible).

> nor what is actually important here and seem fixated on performing
> a totally unneeded and misguided repair to make your furnace "look"
> better...

I never said this was about appearance.

Message has been deleted

Twayne

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Nov 7, 2010, 5:59:29 PM11/7/10
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In news:4CD5D27E...@Guy.com,
Sum Guy <S...@Guy.com> typed:
> I'm looking for some high-temperature sealant / caulking to
> use on my furnace (instead of using duct tape or aluminized
> tape). This is for seams in the usual places where air
> tends to leak out of the duct work and where the furnace
> connects to the ducts. This is not for the flue.
>
> I expect the max temperature to be around 200C, and mostly
> between 50C and 100C.
>
> I was searching the net for specs on GE's various sealant
> products, but can't find very much about max service
> temperature.
>
> Here's an example of what I can buy at home depot (Canada):
>
> http://tinyurl.com/2baqhwj
>
> This might be different than what's available in the USA
> (perhaps only the label is different, or maybe the
> formulation is different - I don't know).
>
> Home Depot in Canada doesn't sell a caulking / sealant
> product that's specifically labeled as "high temperature",
> or furnace, stove or HVAC duct use.
>
> What I did find at HD is 3 different 3M caulk products,
> labelled variously as "Fire Barrier" Sealant IC 15WB (and
> two others that had a similar application). These are
> designed or marketed as sealants that are applied in
> drywall seams and around pipes and wires as they pass
> through walls (drywall, brick, cement, etc) and I guess
> they're meant to contain fire or smoke for maybe an hour or
> two. I did find on-line cheps for one of them - and it had
> a paltry max service temperature of 48C.
>
> I imagine that a job-shop HVAC supplier would probably have
> high-temp caulking, but I'm just curious if something like
> the GE Silicone II would do just as well (200C really
> isin't high-temp).

Read the product labels and don't forget about expansion/contraction of the
metalwork. Personally I'd use the heat-resistant tape made for just such
things.

HTH,

Twayne`


zek

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Nov 8, 2010, 10:01:55 AM11/8/10
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On Nov 6, 6:24 pm, Joe <jbob...@aol.com> wrote:
> Years ago GE made a silicone sealant with red iron oxide filler that
> was rated for high temperature service. IIRC, there are still versions
> of this material available in auto parts stores and perhaps industrial
> supply houses. Silicone II in my experience is not a very good product
> compared to the the original types.
>
> Joe

400 F is normal and Hi temp 500 F

chaniarts

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Nov 8, 2010, 10:31:19 AM11/8/10
to
Sum Guy wrote:
> DanG top-poasted and unnecessarily full-quoted:
>
>> Pure silicone is not good about staying stuck to materials for the
>> long haul. You would be better served to look into hard cast duct
>> sealant.
>
> I doubt that consumer-grade sealants are pure silicone. And besides,
> the tub and bath and exterior door and window sealant product seem to
> stick pretty well for the long haul.
>
> Again, all I want to know is the max temperature that GE Silicone II
> (door and window) can be continuously exposed to without breaking
> down, running or coming off.

what did GE say when you called the 800 number that's on every tube?


Bob F

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Nov 13, 2010, 12:54:03 PM11/13/10
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Jim Yanik wrote:
> Sum Guy <S...@Guy.com> wrote in news:4CD5D27E...@Guy.com:
> go to any auto parts store and buy the High-temp gasket stuff made by
> Permatex. It will tell you on the package it's max temp ratings.

Or buy high-temp silicone at a woodstove store. My local plumbing store even
carries it. Works fine on wood stove exhaust pipe.


Sum Guy

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Nov 6, 2010, 6:11:10 PM11/6/10
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Frank

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Nov 6, 2010, 6:28:22 PM11/6/10
to

I used a clear silicone, think it was the type I, to seal around glass
doors on fire place. Holds up well.

Sum Guy

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Nov 6, 2010, 6:35:48 PM11/6/10
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"A. Baum" wrote:

> Well considering your hight temp cut off is around 90c I would
> work with that figure.

There are seams that run close to where the flue exits the furnace that
will quite likely exceed 100C for extended periods.

Jim Yanik

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Nov 6, 2010, 6:46:54 PM11/6/10
to
Sum Guy <S...@Guy.com> wrote in news:4CD5D27E...@Guy.com:

> I'm looking for some high-temperature sealant / caulking to use on my

go to any auto parts store and buy the High-temp gasket stuff made by

Permatex. It will tell you on the package it's max temp ratings.

--
Jim Yanik
jyanik
at
localnet
dot com

Sjouke Burry

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Nov 6, 2010, 6:58:59 PM11/6/10
to
I have seen 400-500 degree celcius mentioned for
silicon and you can sort of verify that with a
soldering iron.
That should not make it melt down.
At higher temps it turns into a white powder, without
melting, and starts smouldering..

Joe

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Nov 6, 2010, 7:24:55 PM11/6/10
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On Nov 6, 5:11 pm, Sum Guy <S...@Guy.com> wrote:

Years ago GE made a silicone sealant with red iron oxide filler that

The Daring Dufas

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Nov 6, 2010, 7:45:54 PM11/6/10
to

Industrial and commercial cooking equipment supply houses sell high temp
silicone sealant. What I have used is red in color it will handle up to
500�F. Look at Dow Corning 736.

http://www.dowcorning.com/content/publishedlit/80-3258.pdf

TDD

ransley

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Nov 6, 2010, 8:04:16 PM11/6/10
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On Nov 6, 5:11 pm, Sum Guy <S...@Guy.com> wrote:
> caulking , but I'm just curious if something like the GE Silicone II

> would do just as well (200C really isin't high-temp).

Buy the Duct oastic sealer made for that job, its in gallon tubs and
costs 1/5th to 1/3rd what silicone costs. The work is done every day
by pros and they dont use expensive silicone. This stuff you just use
a putty knife and it goes fast.

Sum Guy

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Nov 6, 2010, 8:15:34 PM11/6/10
to
ransley wrote:

> Buy the Duct oastic sealer made for that job, its in gallon tubs
> and costs 1/5th to 1/3rd what silicone costs.

Is it available in Canada?

Is it sold at retail, over the counter, at a place that's open past 5 pm
weekdays or open saturday?

Is it sold at only one place in my city, clear across town in industrial
east end?

Or did you factor in any of that criteria?

Sum Guy

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Nov 6, 2010, 8:19:29 PM11/6/10
to
I'd still just like to know how the home-owner-grade silicone caulking
sold at the big-box stores would stand up to extended exposure to high
temperatures.

According to this:

http://www.grainger.com/Grainger/GE-Waterproof-Sealant-4UH03?Pid=search

Grainger is listing the temp range of that product as being -65f to
400f. It appears to be the same product as this:

http://tinyurl.com/2baqhwj

But I would love to track down an actual GE technical spec sheet for it.

ransley

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Nov 6, 2010, 9:52:22 PM11/6/10
to

Why should I factor in anything, im trying you give you help, a proven
method, but your just being an ass. Anyway, Here I can get it retail,
over the counter, at a place open till 8 on even sunday, and its not
to far from me, sure you have it in Canada, so have fun looking, jerk.

Hot Soup

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Nov 7, 2010, 12:56:48 AM11/7/10
to
Sum Guy <S...@Guy.com> wrote:

>I'd still just like to know how the home-owner-grade silicone caulking
>sold at the big-box stores would stand up to extended exposure to high
>temperatures.

Like ransley said, mastic is what you need. It's sold at Home
Depot/Lowes/etc in the States...dunno about Canada. Look in the aisle
with the ductwork pieces.

Silicone will work if you like paying more for less. Your call.

Supply temps for a forced air furnace aren't 'high temp' - maybe 120F.
That's well within the range of silicones.

Sum Guy

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Nov 7, 2010, 1:09:40 AM11/7/10
to
Hot Soup wrote:

> > I'd still just like to know how the home-owner-grade silicone
> > caulking sold at the big-box stores would stand up to extended
> > exposure to high temperatures.
>
> Like ransley said, mastic is what you need.

It's not the ductwork that I want to seal. It's more like the furnace


itself, where the plenum meets the furnace, even some places inside the
furnace cabinet, places that run close to some very hot surfaces, places
where it would be hard to get a trowel into, places where a nozzle could
easily reach and inject material.

> Silicone will work if you like paying more for less. Your call.

One tube of silicone for maybe $6 - $8 vs I-don't-know for a pail of
mastic. It's not the $$$ that's the issue here.

Evan

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Nov 7, 2010, 4:11:01 AM11/7/10
to

"Places inside the furnace" which probably have no business being
"sealed up" as they were not sealed at the factory...

You do realize that even if you use mastic to seal the joints and


seams
in your duct work that mastic would have to be reapplied every time
someone opens up those ducts to do service...

Why do you feel the need to make your furnace unit more difficult to


take apart by adding silicone caulking to it in areas where it doesn't
need to have it applied...

The goal is to seal the duct work to prevent conditioned air (whether


heated or cooled) from leaking out into unconditioned spaces whether

that be your basement or attic... Attempting to apply sealant onto


parts of the furnace unit where the heated or cooled air are not
exposed to is a foolhardy endeavor which will not result in any

energy savings whatsoever...

As to your questions in your first posting:

NO, the "fire barrier" sealant is not that kind of caulking... It
fills gaps
where wires, pipes, etc. penetrate a wall and will expand to seal
tightly
around those penetrations when it gets heated by a fire and such
sealants are considered "intumescent" and used in passive fire
protection in the manner described...

Using silicone caulking on duct work seems to be silly since there is


another product which is used by competent professionals for the
one of the situations you wish to apply the silicone caulking to...

http://www.alpinehomeair.com/viewproduct.cfm?productID=453059205

Is what you need to find... I am sure that you should be able to
find a source for that mastic in Canada -- it may have simply
been a matter of NOT KNOWING WHAT YOU WERE LOOKING FOR...

~~ Evan

ransley

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Nov 7, 2010, 7:12:34 AM11/7/10
to
> ~~ Evan- Hide quoted text -
>
> - Show quoted text -

You told him Mastic, thats a mistake, now he will want you find a
store that has it, to pick him up, drive him to a store that has it,
buy him a burger, drive him home and show him how to use it, all for
free. But this guy should be paying for your advice now

Sum Guy

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Nov 7, 2010, 8:28:57 AM11/7/10
to
Evan wrote:

> > It's not the ductwork that I want to seal. It's more like the
> > furnace itself, where the plenum meets the furnace, even some
> > places inside the furnace cabinet, places that run close to
> > some very hot surfaces, places where it would be hard to get
> > a trowel into, places where a nozzle could easily reach and
> > inject material.
>

> "Places inside the furnace" which probably have no business
> being "sealed up" as they were not sealed at the factory...

It's a 30-year-old furnace. Lots of slop in how things fit in some


places. Rust in other places have opened up some seams.

> You do realize that even if you use mastic to seal the joints and


> seams in your duct work that mastic would have to be reapplied
> every time someone opens up those ducts to do service...

Hey, I'm not the one advocating mastic. But then again, I don't think


that ducts need to be opened up very often to do servicing...

> Why do you feel the need to make your furnace unit more difficult
> to take apart by adding silicone caulking to it in areas where
> it doesn't need to have it applied...

When there is air blowing through or being sucked through seams, I think


that's a good indication that it probably shouldn't happen. Like when
heated air is escaping through seams where the ductwork is connected to
the furnace. These are seams that are really never taken apart as part
of normal servicing. And if they ever are taken apart, it's probably to
replace something pretty substantial (like the entire furnace). It's
not like I'm going to silicone seal any service doors or panels
(hmmm...)

> The goal is to seal the duct work to prevent conditioned air


> (whether heated or cooled) from leaking out into unconditioned
> spaces whether that be your basement or attic...

And it's also to seal the ducts and passages that pull return air into


the furnace, to prevent the furnace fan from creating a negative air
pressure around the furnace that would lead to air being pulled down
from the flue and creating a reverse air flow in the burner chamber that
cause combustion flames to leap out of the combustion area and into the
area where the thermostat and gas valves are located, and heating and
melting any wiring in that area.

> Attempting to apply sealant onto parts of the furnace unit where


> the heated or cooled air are not exposed to is a foolhardy

> endeavor which will not result in any energy savings whatsoever..

Inside the furnace itself is where you will find places where
conditioned air can escape and where incoming return air passages are
not contained against leakage.

> Using silicone caulking on duct work

Again, it's not the ductwork (distribution runs) that I want to seal


with caulking. It's basicically any of the ductwork in the furnace room
itself, of which there is not really any ductwork as much as the main
distribution and collection plenums or manifolds, air-filter enclosure,
where those structures tie into the furnace, and even some places on or
in the furnace enclosure.

> seems to be silly since there is another product which is used


> by competent professionals for the one of the situations you
> wish to apply the silicone caulking to...

Again, that material might be fine and appropriate to apply during


initial ductwork fabrication and installation. It is not the
appropriate product to use for the situation I'm describing.

> http://www.alpinehomeair.com/viewproduct.cfm?productID=453059205


>
> Is what you need to find...

Interesting item listed in it's specifications:

http://www.alpinehomeair.com/_viewresource.cfm/ID/1363/p/Thermal%20Mastic%20Compound%20Product%20Data

Sum Guy

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Nov 7, 2010, 8:31:18 AM11/7/10
to
ransley unnecessarily full-quoted:


> You told him Mastic, thats a mistake, now he will want you find a
> store that has it,

No, because I don't want to use mastic.

I just want to know what the max service temperature that GE Silicone II
can be exposed to.

But nobody can answer that question, so they go off on tangents about
this mastic shit.

DanG

unread,
Nov 7, 2010, 8:59:11 AM11/7/10
to
Pure silicone is not good about staying stuck to materials for the
long haul. You would be better served to look into hard cast duct
sealant. It is normally applied with a paint brush, roller, or
putty knife. It is also offered in caulk tubes. Here is an
example:

www.hardcast.com/products/PDFS/broch/HCS_02_05.pdf--
~~~~~~~~~~~~~~~~~~~~
DanG
Keep the whole world singing . . .


"Sum Guy" <S...@Guy.com> wrote in message
news:4CD5D27E...@Guy.com...

Sum Guy

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Nov 7, 2010, 9:17:32 AM11/7/10
to
DanG top-poasted and unnecessarily full-quoted:

> Pure silicone is not good about staying stuck to materials for the
> long haul. You would be better served to look into hard cast duct
> sealant.

I doubt that consumer-grade sealants are pure silicone. And besides,

Smitty Two

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Nov 7, 2010, 11:14:39 AM11/7/10
to

You can answer it. Don't be so helpless. This is a DIY group, after all.
Stick a couple of pieces of 30 year old, rusty furnace-type metal
together with some GE Silicone II and expose it to some heat in your
oven.

Start at 200F for 3 hours, then crank it up in whatever increments you
feel like, leaving it for 3 hours each time. Use a couple of pairs of
pliers to test the integrity of the bond. Watch for fires, melting,
explosions, or any signs that the GE Silicone II might be morphing into
radioactive waste or alien life.

Publish an article detailing the results of your research on eHow, so
future generations will know to what temperature GE Silicone II can
safely be exposed. I'm going to be waiting, because I want to use it to
seal the leaks in my car's exhaust system.

Jack Reed

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Jul 4, 2017, 6:44:04 PM7/4/17
to
replying to Sum Guy, Jack Reed wrote:
392 degrees Fahrenheit isn't really high-temp?

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Tiago50

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Oct 1, 2017, 10:14:05 PM10/1/17
to
replying to Jack Reed, Tiago50 wrote:
I know this is an old thread, but here is the data from the MSDS:
This product contains methylpolysiloxanes whic
h can generate formaldehyde at approximately 300
degrees Fahrenheit (150'C) and above, in atmosphe
res which contain oxygen. Formaldehyde is a
skin and respiratory sensitizer, eye and throat irrit
ant, acute toxicant, and potential cancer hazard. A
MSDS for formaldehyde is available from Mo
mentive., Methanol released during curing.

You might want to look at using another type of sealant.

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Evan needs a daddy

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Oct 4, 2018, 9:14:03 PM10/4/18
to
replying to Evan, Evan needs a daddy wrote:
Dude, You are a dick! Just admit you don't know the answer and politely bow
out of the conversation. Talking about shit you may have heard one of your
mom's sugar daddies talking about in passing isn't earning you any points with
the folks who actually know what they are talking about. Just because you
aren't mentally capable doesn't mean others are similarly deficient. Some of
us actually made it through highschool and *gasp* into college where we
*double gasp* learned stuff - ya know - like En-gen-eer-ing...

The max operating temp for GE II is 400F.

Stay out of the way and let the big boys work!

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Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Why do we still have to be so unkind to a curious, learner ? Thanks for your advice, but does it have to be insulting ? Is this the way you speak to people in person, like your customers, etc ? If you know more, please share, but not with all the judgement, etc.
Anyone ever used Black Fire Cement ? used to seal wood stoves,etc high temp ? G

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Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Wow, thank you. See, no-one predicted that answer. Formaldehyde is some nasty s----(stuff). Glad for your input.

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Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Idea solution : I'm reading that you need the tube for ease and ability of application.
Is there a way to place the mastic into a calling tube and squirt it on/in ? Does the mastic have the right viscosity to be squeezed out of a calling tip ? If so, this mastic wud work for both use cases. Does mastic hold up to furnace temps ? 350 - 750 deg F -G

Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Have you tried contacting the manufacturer ?
My sister asked me to find out (internet search) how long her battery is supposed to last (hours/days) for her model cell phone. I told her the real information answer, for her use case, will be so specific to her, that she needs to just try a different (newer) phone and use it as she normally would, to find out how long a typical battery should last. And I offered her my phone. Which means a better answer is to find out under your own specific conditions.
I think if anyone has a good answer for the GE silicone temperature limit question, they wud have written it. Since they/we don't, they/we recommended known options. It may be time to do your own testing/experimenting and find out for all of us, if ithe GE silicone works at ___ temp, and for how long does it stick. This will help forward knowledge, if you choose to share it, for all humankind. G
PS Have you tried to find a product called "_/*_Black Fire Cement_*/_ " ? Its used for sealing wood stoves, etc. (high temp). Pls let us know what works.

Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Please behave like an adult now. Language. We are all learning from every comment. I have an application where I'd like to make an easy mold of something, so I can reproduce it by pouring molten lead or solder into the mold (mold made of something that begins as plastic (soft) and hardens to a rubbery consistency, but can take high heat of molten solder or lead. All of these products look like they might be good candidates and work (or not). I believe solder melting point is 360-370 deg F (180-190C) but can be as high as near 600 deg F, depends on the alloy/blend.
So Mr Ransley, if you would be so kind as to please let me know the exact name of the product to which you are referring, as it looks like a typo in your comment. Did you mean to say "HVAC duct seal mastic ?" Does it have a number in the name or any other descriptor ? Please help + be more specific and please take a deep breath, + please do not resort to cavemanish name-calling, when you are frustrated. Oops, now I may have just done the same. Thank you, Greg PS I've noticed, people from Canada are really compassionate, polite, and kind-natured, like the better part of ourselves . And this was all meant with humility + respect to everyone.

Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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Why is it so hard for people to be nice to each other ? How was that last comment helpful ? Why not give him an actual product name that you recommend ? I worked alongside an HVAC friend for 10 yrs "apprenticing," and the guys in the business used a mastic product called CCWI (I forget the number- 181 ?) pros, please help. I think there are different viscosities with different numbers like # 6 or 7. Its worth doing a little research b4 ordering online or purchasing. Also, not sure if they were designed (don't think so) for inside furnace temps. And then you have the high temp aluminum tape, which you originally said you'd rather not use, as it has a lifetime (and death) of its stickiness (I agree). Mastic is longer lasting.
Have you thought about creating a trap door in your ductwork, with an angel grinder, for easier access, for inspecting, sealing and cleaning ? But then you have to make a door which is bigger than the opening and seal around that too . This is quite an interesting exchange of ideas. Thank you all. G

Idea Factory

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Dec 31, 2021, 11:45:05 AM12/31/21
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BTW, many of us in the States, have no idea that a furnace boiler, which has a blower to focus or fan the oil flame, actually blows hot air and combustion gases, which are more toxic than car exhaust, since no catalytic converter, thru the combustion chamber, and over the manifolds/baffles/ heat exchanger, *out* of the chimney (out of the house) and therefore, creates a vacuum(negative pressure) in the house. Air must replace it, best case: comes from outside, generally cold air, thru leaks or at best a separate in duct, which does not seem very efficient, since we do not generally use heat exchangers (for "in" air) here in residential HVAC. Worst case, pulls back chimney exhaust gases (including Carbon Monoxide) as you correctly should be concerned . I know in new res construction, in Canada, heat exchangers are used, with separate "in" air ductwork, and in Germany. Seems we in US are still in the Stone Age. The last oil furnace/boiler guy who came to service ours last month, said the boiler does not have a blower, when I asked him. So he's either ignorant or he's fudging to shut the homeowner's questions down. If you have a separate fossil fuel fired water heater, with a separate duct for exhaust gases, and the furnace is creating a vacuum, guess what happens to the H2O heater exhaust gases ? They come right back in .
Pros out there, please correct me if I'm wrong, - I'm just a kid and only did an apprenticeship with an old man in HVAC. I'm not a pro.
There are mastics which dry rubbery. But please try the silicone,(perform the experiment) be the scientist, and let us all know what the temp is (drill a test hole/port) if it works. If it sticks, if it stays rubbery, how long it lasts. You can forward knowledge for all of us humans, even those who think they already know everything. I can tell all of us are burning with curiosity, insults aside. I know I am. I wonder if they treat their neighbors the way they behave online. Online writing Seems to bring out the "best" in all of us. Black Fire Cement ?

Idea Factory

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Dec 31, 2021, 11:45:06 AM12/31/21
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Hey Big Boy, Why do you find it necessary to name-call and insult ? That is bullying. You do realize you "spelt Engineering" incorrectly. How did your comment forward (the knowledge) of the discussion ? Shutting down an inquisitive pupil ? Hope you don't work in a position that you have to explain things or teach or work with things that live and breathe or interact with children like this. You don't have to have an engineering degree to understand physics and concepts of materials science and thermodynamics. We all can learn just about anything, if so motivated. Just like you did - you didn't know something about something , until you did. We all can be many things. Try not to beat the curiosity out of people, who want to learn.

I was wondering about muffler and tailpipe sealer - but that is probably not rubbery after cure _ G

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