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Should metal chimney liners be grounded against lightning strikes?

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andyeverett

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Apr 7, 2011, 7:50:58 PM4/7/11
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I was at a home today which a while back had a lightning strike the
chimney and explode the top of the chimney off. On the drive home I
got to thinking, I have two metal chimney liners, one for a first
floor wood-stove and another for the furnace and only the furnace
liner is indirectly grounded, I guess, via the furnace ground. If TV
antennas need to be grounded should chimney liners be grounded as
well?

Thank you for your thoughts!

HeyBub

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Apr 7, 2011, 9:21:49 PM4/7/11
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Can't hurt.

Put up a lightning rod, which doesn't ground anything, to discourage
lightning in the first place.


bob haller

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Apr 7, 2011, 9:37:53 PM4/7/11
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lightning rods dont discourage lightning they just give it a safe path
to ground minimizing building damage ....

bob haller

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Apr 7, 2011, 9:38:30 PM4/7/11
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I would ground the chimeny liner

Message has been deleted

Bill

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Apr 7, 2011, 11:13:05 PM4/7/11
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<gfre...@aol.com> wrote in message
news:75qsp6p6g1hj7rs52...@4ax.com...
> I would put a lightning rod on top of the chimney and run a wire
> down
> to a rod below.

Yes install a proper lightning rod, proper size ground wire run
outside the building, and to proper ground rod(s). (Or don't do
anything at all.)

harry

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Apr 8, 2011, 3:47:34 AM4/8/11
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Yes if you are on top of a hill especially. You are more likely to be
struck and the ground resistance will be higher. If there are higher
objects nearby (trees or other buildings) you are less likely to be
struck.

The damage is done at the points of highest resistance due to the
heating effect.

The expensive bit is creating a good earth/ground point to attach to.

Hank

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Apr 8, 2011, 5:12:14 AM4/8/11
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If you ground it, don't compromise the integrity of the liner by
drilling a screw hole. Liners are usually stainless steel and hard to
drill through, that's a good thing. Use a clamp. Drilling through the
liner MAY create a small leak where heat can escape causing a fire.

Hank

andyeverett

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Apr 8, 2011, 7:23:49 AM4/8/11
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We are on a slight ridge but there are many tall trees around. I hope
trees make a good path to ground? I was thinking of installing an
external TV antenna which would force me to ground it. I guess the
liners could be tied in as well.

I guess I should talk to our insurer.

Thank you all for your help!

LSMFT

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Apr 8, 2011, 7:55:48 AM4/8/11
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HeyBub wrote:


--
All is as it is.

If you ground a metal liner you will just attract the lightening,
something you don't want. If lightening will blow the bricks off a
chimney which is not a conductor, I don't think lightening cares where
it strikes. If you ground it and it attracts lightening it could still
blow the top of your chimney off. A higher lightening rod may attract it
instead, (may). It's not an exact science.


--
All is as it is.

LSMFT

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Apr 8, 2011, 7:53:36 AM4/8/11
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If you ground a metal liner you will just attract the lightening,

LSMFT

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Apr 8, 2011, 7:54:56 AM4/8/11
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If you ground a metal liner you will just attract the lightening,

Stormin Mormon

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Apr 8, 2011, 8:34:22 AM4/8/11
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I've worked on enough chimney liners. Used to help install
them when I did HVAC. The flue gasses aren't hot enough to
start a fire, through a screw hole. The metal liner cools
the gasses a lot. A screw hole won't lead to a fire.
However, grounding the liner may increase the chances of
lightning strike. Only slightly, the metal liner is clamped
to some appliance which should be grounded already.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


"Hank" <nineb...@aol.com> wrote in message
news:442312a7-d61a-4dd6...@m13g2000yqb.googlegroups.com...

tra...@optonline.net

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Apr 8, 2011, 8:48:19 AM4/8/11
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Following that theory, I guess we should remove grounding from
roof mounted TV antennas and cable dishes too.

bud--

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Apr 8, 2011, 10:06:29 AM4/8/11
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I agree that if you want protection add a lightning rod. The earthing
system for a ground rod has to be tied to the earthing system of the
electrical system. For most of us the probability of being hit is quite low.

Ordinary antennas are not earthed to protect from lightning strikes -
the earthing system is not heavy enough. Hams may expect their much more
extensive antennas to be struck by lightning, which requires a more
extensive earthing system.

Earthing an antenna (or flue) will not attract lightning. As haller
wrote a lightning rod is just a safe point for lightning to strike.

--
bud--

Mark

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Apr 8, 2011, 10:18:48 AM4/8/11
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>
> If you ground a metal liner you will just attract the lightening,
>

This is NOT correct...

Mark

Hank

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Apr 8, 2011, 1:22:58 PM4/8/11
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On Apr 8, 8:34 am, "Stormin Mormon"

<cayoung61**spambloc...@hotmail.com> wrote:
> I've worked on enough chimney liners. Used to help install
> them when I did HVAC.   The flue gasses aren't hot enough to
> start a fire, through a screw hole. The metal liner cools
> the gasses a lot. A  screw hole won't lead to a fire.
> However, grounding the liner may increase the chances of
> lightning strike. Only slightly, the metal liner is clamped
> to some appliance which should be grounded already.
>
> --
> Christopher A. Young

Tell that to my friend who lost his house when the installers put a
screw thru the lining. Also, when a chimney, esp. metal ones, build up
creosote and catch fire, they get really really hot. Ever seen one on
fire? I have seen quite a few since I am a retired firefighter of 28
years. They get red hot and sound like a jet engine.

If you put screws thru the liner, you did it wrong.

Hank

tra...@optonline.net

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Apr 8, 2011, 2:19:28 PM4/8/11
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I'd say it all depends on what kind of chimney liner it is and what
it's used
for. A chimney liner for a fireplace is a very different application
than one
for a gas water heater. And a chimney liner relies on the existing
chimney
for thermal protection, does it not? I don't see how a sheetmetal
screw
through the end of a gas water heater chimney liner is going
to result in something bad happening. Put a screw through a class A
steel chimney for a fireplace and it could be very different.

Hank

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Apr 8, 2011, 3:11:15 PM4/8/11
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On Apr 8, 2:19 pm, "trad...@optonline.net" <trad...@optonline.net>
wrote:
> steel chimney for a fireplace and it could be very different.-

I was talking about a WOODBURNING fireplace chimney that is not
inside a masonry chimney. Most of the new houses today have metal
chimneys inside a wood structure. The metal chimney is supported by
straps. A have seen installers put screws in the chimney and make
their own straps when the attached standard strapping isn't in the
same place as the wooden frame work. Even masonry chimneys build up
creosote and catch fire. And if there is a crack in the masonry, it
can cause structual damage.

Hank

hr(bob) hofmann@att.net

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Apr 8, 2011, 3:36:31 PM4/8/11
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> All is as it is.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

Lightening is what Michael Jackson did to his face. Lightning is what
happens when clouds build up dissimilar charges and there is a giant
spark between the clouds or between the coulds and the earth.

Stormin Mormon

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Apr 8, 2011, 3:53:28 PM4/8/11
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The liners I installed, three is no way the flue gasses get
hot enough to start a fire. Actually, the water heaters use
single wall 26 gage galvanized duct before we put the liners
in. Not gonna start any fires.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


"Hank" <nineb...@aol.com> wrote in message

news:0a09391d-06ac-4fa2...@u12g2000vbf.googlegroups.com...

Stormin Mormon

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Apr 8, 2011, 3:54:59 PM4/8/11
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I have helped install a lot of liners for NATURAL GAS
BURNING water heaters, and other appliances. I've never seen
CREOSOTE in such a chimney. Neither have I seen flue gasses
hot enough to START A FIRE.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


"Hank" <nineb...@aol.com> wrote in message

news:32d47891-1655-47c5...@l30g2000vbn.googlegroups.com...

Tony Hwang

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Apr 8, 2011, 4:49:27 PM4/8/11
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Hi,
If you worry about it, how about eaves trough?
Too many things to ground around the house.
We are always exposed to lightning, if got hit direct,
nothing much will withstand no matter what.

LSMFT

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Apr 8, 2011, 6:08:47 PM4/8/11
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And it could enlighten you.

Smitty Two

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Apr 8, 2011, 6:58:45 PM4/8/11
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In article
<18e1f7c2-dd2d-4dbd...@e21g2000yqe.googlegroups.com>,
"hr(bob) hof...@att.net" <hrho...@att.net> wrote:

> Lightening is what Michael Jackson did to his face. Lightning is what
> happens when clouds build up dissimilar charges and there is a giant
> spark between the clouds or between the coulds and the earth.

Coulds* are things that might transpire. Clouds are things that float in
the sky.

(*nounthrapomorphism applied)

hr(bob) hofmann@att.net

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Apr 8, 2011, 10:34:04 PM4/8/11
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On Apr 8, 5:58 pm, Smitty Two <prestwh...@earthlink.net> wrote:
> In article
> <18e1f7c2-dd2d-4dbd-b183-9f34eca0d...@e21g2000yqe.googlegroups.com>,

>  "hr(bob) hofm...@att.net" <hrhofm...@att.net> wrote:
>
> > Lightening is what Michael Jackson did to his face.  Lightning is what
> > happens when clouds build up dissimilar charges and there is a giant
> > spark between the clouds or between the coulds and the earth.
>
> Coulds* are things that might transpire. Clouds are things that float in
> the sky.
>
> (*nounthrapomorphism applied)

I never could spell any word correctly more than 2 times.

Tekkie®

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Apr 21, 2011, 2:45:47 PM4/21/11
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andyeverett posted for all of us...

>
> I was at a home today which a while back had a lightning strike the
> chimney and explode the top of the chimney off. On the drive home I
> got to thinking, I have two metal chimney liners, one for a first
> floor wood-stove and another for the furnace and only the furnace
> liner is indirectly grounded, I guess, via the furnace ground. If TV
> antennas need to be grounded should chimney liners be grounded as
> well?
>
> Thank you for your thoughts!

Don't know about the chimney liners but being a fireman went to a few chimneys
blasted apart, in fact one down the street from me. So nature always wins...

I would place a properly installed lightning rod and make certain the whole
house electrical system is up to snuff.

--
Tekkie

Unknown

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Jun 17, 2021, 9:33:30 AM6/17/21
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bud--

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Jun 17, 2021, 11:42:12 AM6/17/21
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On 6/17/2021 7:33 AM, R. Golden wrote:
> Common misconception.
>

Unfortunately 9 1/2 years ago the OP was on a ladder to ground the
liner, and fell off. A timely response from you, like 9 3/4 years ago,
may have saved his life.

Do people who use the homemoaners hub actually have to fail an
intelligence test, as has been reported on the internet?

hub...@ccanoemail.ca

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Jun 17, 2021, 12:01:18 PM6/17/21
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... if you catch them smoking .. :-)
Joihn T.

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