Just had two chimney liners installed for both the 1st floor wood stove
and the basement oil furnace. We have a grounded TV antenna which is two
feet from the liners. Does it make sense to ground the liners to the
same ground system as the TV antenna.
Thank you for any help in this matter.
This is an new question to me.
The NEC basically says that all metal piping systems should be grounded.
Water, and gas are bonded by an conductor. A/c ducting is screwed to the
unit so there is a bond there. The oil furnace is grounded cause of the
motor connection you would think.
Wood stove is well not powered so it is non grounded. Comes the question
What are you trying to do? If your thinking that grounding the liners is
lightning protection your sadly mistaken. If lightning is an issue then you
really should look into a couple of finials and some cable. Grounding the tv
antenna is only an sacrificial ground. If it gets hit by lightning,
everything connected to it by either the coax or by power is probably going
to be fried.
I would ask your local building official to be sure.
A most serious protection system earths any conductive
metal, within 2 meters of the downlead. That earthing must be
to same earth ground as that downlead. IOW adjacent metal
remains electrically isolated from the lightning conductor
until they both meet at the same earth ground.
That is the concept in its purest form. You may not need
such extreme measures. Yes, earthing the chimney liner to
earth ground would be a better idea. But then a simpler and
more effective solution may be to enhance - expand - the
antenna's earth ground. How likely is a direct lightning
strike going to strike the chimney liner? The better that
antenna earth ground, then the more protected that chimney
liner. Quality of that earth ground and using a earthing wire
of 6 AWG or larger would earth most direct lightning strikes
What earth is the building located - both on the surface and
10+ feet beneath? If constructed in sand, then the antenna's
earthing system must be substantial. Furthermore, that
earthing is best installed with a buried connecting wire from
antenna earth ground to the building's single point earth
ground. That buried conductor both improves the antenna as a
lightning rod AND enhances the entire building's earth ground
Posted here is dependent on many details such as how the
building is constructed, underlying geology, and history of
direct strikes to neighborhood buildings. Provided are basic
concepts of a good protection system. It is rare for
lightning to find earth ground via a chimney liner. Almost
impossible if the adjacent antenna is well earthed - acting as
a Franklin lightning rod.
andy everett wrote:
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.