What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

On May 23, 4:38*pm, Bryan Scholtes wrote:
What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

There is a substantial earth leakage current nearby causing a voltage
gradient.. It could be in a nieghbours house or i the supply companies
electrical system. There may well be faults in the grounding of your
system.
This is potentially lethal and needs looking at.
Both for electric shock potential and fire starting.

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.


*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. However you did mention the
installation of a house ground wire. Was a new ground rod installed? Are
all of the pipes bonded? How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

On May 23, 11:55*am, "John Grabowski" wrote:
What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. THIS IS POTENTAILLY LIFE-THREATENING!!!

Maybe the HVAC is charged?

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


"Bryan Scholtes" wrote in message
...

What could cause conduit to arc where it touches another
conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house
ground
wire in a home improvement project. A licensed electrician
installed
the breakers and made the box connections. I assume he did
it
correctly.

Here's the problem:

I installed a basement HVAC duct touching an old metal
flexible
conduit. A few weeks later, I noticed arcing between the
conduit and
HVAC duct where they touched. Neither of the two shocked me
when I
touched them, but sure enough - an orange arc was making a
little
noise. Upon examination, the arcing had welded holes in the
HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside
were fine
- one was a bit darkened. Over a few weeks, I expected much
worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen
light
fixture on a different circuit. The box was hot to the
touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER - that box's conduit was touching another conduit,
and sure
enough - a little hole had been welded where they had been
touching.

What could be causing this? I am a little spooked.

On May 23, 3:38*pm, "hr(bob) "
wrote:
On May 23, 11:55*am, "John Grabowski" wrote:



What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan

On May 24, 3:23*am, Evan wrote:
On May 23, 3:38*pm, "hr(bob) "
wrote:





On May 23, 11:55*am, "John Grabowski" wrote:

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching..

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... *

You have a reference where it says that in the code? If so,
there must be a hell of a lot of illegal installs. A typical
example would be a furnace where metal conduit was
used to run power to the furnace and the the conduit
is fastened with metal clamps directly to the furnace
housing along it's run and to the metal connection box.
That in turn means that the entire metal duct system
is connected to the metal conduit. So is the metal
gas pipe connected to the furnace and everything
connected to that piping system.




When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

If wiring were done that way, there would sure be some
strange looking conglomerations out there.





As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

From what I've heard so far, this is his only real problem.





You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan- Hide quoted text -

- Show quoted text -

On May 24, 8:10*am, "
wrote:
On May 24, 3:23*am, Evan wrote:



On May 23, 3:38*pm, "hr(bob) "
wrote:

On May 23, 11:55*am, "John Grabowski" wrote:

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse.. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... *

You have a reference where it says that in the code? *If so,
there must be a hell of a lot of illegal installs. * A typical
example would be a furnace where metal conduit was
used to run power to the furnace and the the conduit
is fastened with metal clamps directly to the furnace
housing along it's run and to the metal connection box.
That in turn means that the entire metal duct system
is connected to the metal conduit. *So is the metal
gas pipe connected to the furnace and everything
connected to that piping system.

When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

If wiring were done that way, there would sure be some
strange looking conglomerations out there.



As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

From what I've heard so far, this is his only real problem.



You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan- Hide quoted text -

- Show quoted text -

As far as the code cite: I don't know chapter and verse,
but the basics of the code not allowing wiring to be in
physical contact with ductwork is that the ducting can
move around as the HVAC system operates and duct
pressure rises and falls and cause mechanical damage
to the wiring over the course of time... All wiring runs MUST
be installed so that they are protected from mechanical
damage... It goes more to that specifically and the general
phrase "all work must be done in a workmanlike manner"
which is something that looms over all electrical installs...

I have forgotten how much clearance must be afforded for
wiring runs near other utility lines but I know for a fact
that there are different rules for clearances depending
on whether you are running the wiring parallel to some
other utility line or perpendicular to another utility line...

I am not a practicing electrician who does wiring in new
homes every day, I do maintenance on existing installs
in commercial buildings and trust me, I know that there
are quite a few code violations out there in otherwise
normal looking buildings because it is sealed up in the
walls or way above a ceiling where an inspector never
looked when signing off on the permits...

I agree with the theory that there is an open or misconnected
neutral somewhere in the OP's house which is now using
the HVAC ductwork and the arcing conduit as a return path
which is very dangerous and could cause a fire... I don't
think it is in any way connected to either of the circuits he
had the electrician install the AFCI breakers on because
those breakers would be tripping if the amount of current
going out on the hot didn't match up with what was coming
back on the neutral -- it is what such breakers are designed
to detect and open the circuit to prevent...

~~ Evan

On May 24, 12:17*pm, Evan wrote:
On May 24, 8:10*am, "
wrote:





On May 24, 3:23*am, Evan wrote:

On May 23, 3:38*pm, "hr(bob) "
wrote:

On May 23, 11:55*am, "John Grabowski" wrote:

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... *

You have a reference where it says that in the code? *If so,
there must be a hell of a lot of illegal installs. * A typical
example would be a furnace where metal conduit was
used to run power to the furnace and the the conduit
is fastened with metal clamps directly to the furnace
housing along it's run and to the metal connection box.
That in turn means that the entire metal duct system
is connected to the metal conduit. *So is the metal
gas pipe connected to the furnace and everything
connected to that piping system.

When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

If wiring were done that way, there would sure be some
strange looking conglomerations out there.

As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

From what I've heard so far, this is his only real problem.

You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan- Hide quoted text -

- Show quoted text -

As far as the code cite: *I don't know chapter and verse,
but the basics of the code not allowing wiring to be in
physical contact with ductwork is that the ducting can
move around as the HVAC system operates and duct
pressure rises and falls and cause mechanical damage
to the wiring over the course of time... *All wiring runs MUST
be installed so that they are protected from mechanical
damage... *

Which the metal conduit that he has that you objected to
provides.






It goes more to that specifically and the general
phrase "all work must be done in a workmanlike manner"
which is something that looms over all electrical installs...

Maybe workmanlike means to you that metal conduits or
raceways can't be in contact with any other metal like
an HVAC duct, but it doesn't mean it to me, nor does it
say it anywhere in the code I am aware of. I can show
you new installs of HVAC that passed inspection here
where conduit is touching metal or fastened directly to it.
In fact, NEC allows metal conduit to be used INSIDE
HVAC ducts. So, it's hard to imagine they have a
prohibition against a metal conduit touching metal
like an HVAC duct anywhere along it's run.






I have forgotten how much clearance must be afforded for
wiring runs near other utility lines but I know for a fact
that there are different rules for clearances depending
on whether you are running the wiring parallel to some
other utility line or perpendicular to another utility line...

When you figure it out, let us know.




I am not a practicing electrician who does wiring in new
homes every day, I do maintenance on existing installs
in commercial buildings and trust me, I know that there
are quite a few code violations out there in otherwise
normal looking buildings because it is sealed up in the
walls or way above a ceiling where an inspector never
looked when signing off on the permits...

I suspect some of the things you think are violations are
in fact not, as is the case in point. You;d have the guy
rewiring his conduit runs, when there is no need to do
so. The only problem in evidence is that current is
flowing in the ground path and that is what needs to
be fixed.





I agree with the theory that there is an open or misconnected
neutral somewhere in the OP's house which is now using
the HVAC ductwork and the arcing conduit as a return path
which is very dangerous and could cause a fire... *I don't
think it is in any way connected to either of the circuits he
had the electrician install the AFCI breakers on because
those breakers would be tripping if the amount of current
going out on the hot didn't match up with what was coming
back on the neutral -- it is what such breakers are designed
to detect and open the circuit to prevent...

~~ Evan- Hide quoted text -

- Show quoted text -

OK - so an update -

The same guy came out and looked at the kitchen fixture. He found some
spots where the ancient cloth insulation had been gradually worn away
by a tiny arc. Then, when he moved the box, it shorted and the circuit
tripped.

We rebuilt the box and fixture, and made sure there were no further
problems.

We're waiting-and-seeing and inspecting everything else on that
circuit. But for now, I am hoping it's OK (famous last words).

In a couple weeks, I'll have another 2 circuits put in my box. We'll
have another chance to inspect everything then.

Am I being too hopeful?

OK - so an update -

The same guy came out and looked at the kitchen fixture. He found some
spots where the ancient cloth insulation had been gradually worn away
by a tiny arc. Then, when he moved the box, it shorted and the circuit
tripped.

We rebuilt the box and fixture, and made sure there were no further
problems.

We're waiting-and-seeing and inspecting everything else on that
circuit. But for now, I am hoping it's OK (famous last words).

In a couple weeks, I'll have another 2 circuits put in my box. We'll
have another chance to inspect everything then.

Am I being too hopeful?


*Ancient cloth insulation tells me that this is an old house. Anything is
possible as a result of age, remodeling, repairs and the people that did
them. Just keep an eye out.

Time to consider rewiring the entire house. Cloth
insullation not been made for many decades, that stuff has
to be ancient. Will be more problems.

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


"John Grabowski" wrote in message
...
OK - so an update -

The same guy came out and looked at the kitchen fixture.
He found some
spots where the ancient cloth insulation had been
gradually worn away
by a tiny arc. Then, when he moved the box, it shorted and
the circuit
tripped.

We rebuilt the box and fixture, and made sure there were
no further
problems.

We're waiting-and-seeing and inspecting everything else on
that
circuit. But for now, I am hoping it's OK (famous last
words).

In a couple weeks, I'll have another 2 circuits put in my
box. We'll
have another chance to inspect everything then.

Am I being too hopeful?


*Ancient cloth insulation tells me that this is an old
house. Anything is
possible as a result of age, remodeling, repairs and the
people that did
them. Just keep an eye out.

In article ,
"Stormin Mormon" wrote:

Time to consider rewiring the entire house. Cloth
insullation not been made for many decades, that stuff has
to be ancient. Will be more problems.

My brother lives in the house in which I grew up, built in 1916. Still
has the original fusebox in the basement, pushbutton light switches
throughout, and none of that silly ground plug or GFCI nonsense. Plenty
of 100 yr. old houses that don't have electrical problems.

On May 25, 11:44*am, "
wrote:
On May 24, 12:17*pm, Evan wrote:



On May 24, 8:10*am, "
wrote:

On May 24, 3:23*am, Evan wrote:

On May 23, 3:38*pm, "hr(bob) "
wrote:

On May 23, 11:55*am, "John Grabowski" wrote:

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... *

You have a reference where it says that in the code? *If so,
there must be a hell of a lot of illegal installs. * A typical
example would be a furnace where metal conduit was
used to run power to the furnace and the the conduit
is fastened with metal clamps directly to the furnace
housing along it's run and to the metal connection box.
That in turn means that the entire metal duct system
is connected to the metal conduit. *So is the metal
gas pipe connected to the furnace and everything
connected to that piping system.

When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

If wiring were done that way, there would sure be some
strange looking conglomerations out there.

As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

From what I've heard so far, this is his only real problem.

You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan- Hide quoted text -

- Show quoted text -

As far as the code cite: *I don't know chapter and verse,
but the basics of the code not allowing wiring to be in
physical contact with ductwork is that the ducting can
move around as the HVAC system operates and duct
pressure rises and falls and cause mechanical damage
to the wiring over the course of time... *All wiring runs MUST
be installed so that they are protected from mechanical
damage... *

Which the metal conduit that he has that you objected to
provides.

It goes more to that specifically and the general
phrase "all work must be done in a workmanlike manner"
which is something that looms over all electrical installs...

Maybe workmanlike means to you that metal conduits or
raceways can't be in contact with any other metal like
an HVAC duct, but it doesn't mean it to me, nor does it
say it anywhere in the code I am aware of. * *I can show
you new installs of HVAC that passed inspection here
where conduit is touching metal or fastened directly to it.
In fact, NEC allows metal conduit to be used INSIDE
HVAC ducts. *So, it's hard to imagine they have a
prohibition against a metal conduit touching metal
like an HVAC duct anywhere along it's run.



I have forgotten how much clearance must be afforded for
wiring runs near other utility lines but I know for a fact
that there are different rules for clearances depending
on whether you are running the wiring parallel to some
other utility line or perpendicular to another utility line...

When you figure it out, let us know.



I am not a practicing electrician who does wiring in new
homes every day, I do maintenance on existing installs
in commercial buildings and trust me, I know that there
are quite a few code violations out there in otherwise
normal looking buildings because it is sealed up in the
walls or way above a ceiling where an inspector never
looked when signing off on the permits...

I suspect some of the things you think are violations are
in fact not, as is the case in point. *You;d have the guy
rewiring his conduit runs, when there is no need to do
so. *The only problem in evidence is that current is
flowing in the ground path and that is what needs to
be fixed.



I agree with the theory that there is an open or misconnected
neutral somewhere in the OP's house which is now using
the HVAC ductwork and the arcing conduit as a return path
which is very dangerous and could cause a fire... *I don't
think it is in any way connected to either of the circuits he
had the electrician install the AFCI breakers on because
those breakers would be tripping if the amount of current
going out on the hot didn't match up with what was coming
back on the neutral -- it is what such breakers are designed
to detect and open the circuit to prevent...

~~ Evan- Hide quoted text -

- Show quoted text -

There is *NO* code approved way to "repair" cloth insulated
wires which have degraded to the point at which they are
throwing arcs that involves anything less than pulling new
conductors... Wrapping conductors with old degraded
insulation in black electrical tape only resolves the symptom
of the actual problem where it is most accessible, it does
nothing at all to solve the problem and eliminate the KNOWN
risk of fire that exists from old conductors which were
observed arcing...

The OP was lucky that his wiring was arcing in a place he
could see and hear it rather than deep inside the conduit
where he would never have known about it or observed it
until after the fire started...

He would have to pull new modern conductors in the old
conduit runs to eliminate the problem he is experiencing...

To address the issues you brought up in your response,
conduit is the one wiring method where you need extreme
force acting upon it to damage it, especially with rigid
threaded conduit... However, with MC or AC flex cable
installing it so that it is in contact with a large metal
duct, where the duct can move and vibrate against the
wire, that is setting yourself up for a wiring failure in the
future from an abraded cable -- the tighter the wire is
pulled to/against the duct or any hard corner which is
capable of and likely to vibrate WILL cause mechanical
damage...

Since the OP looked at several connections and
found rotted cloth wire insulation that had degraded
it is very likely that the insulation has deteriorated
the same way in areas that are concealed and hidden
within the cable and therefore unable to be visually
inspected to assess the safety of the rest of the
installation -- there MUST be more damage as there is
a leak of current out of the circuit that is using the
metal duct as a pathway back to earth...

~~ Evan

On May 28, 10:36*am, Smitty Two wrote:
In article ,
*"Stormin Mormon" wrote:

Time to consider rewiring the entire house. Cloth
insullation not been made for many decades, that stuff has
to be ancient. Will be more problems.

My brother lives in the house in which I grew up, built in 1916. Still
has the original fusebox in the basement, pushbutton light switches
throughout, and none of that silly ground plug or GFCI nonsense. Plenty
of 100 yr. old houses that don't have electrical problems.

Ah, but for whatever reason *this* OP's old house with the old
cloth covered wires has experienced something which is
indicating that it is getting close to the time to remove ALL of the
old wiring and replace it with conductors whose insulation is
not compromised and unsafe... Whether this degradation was
the result of the *lottery winning* history of weather which
dried out the insulation over time, due to past overloading of
the circuits or poor workmanship in the original installation
is as yet unknown and may never be known...

However in this situation the most prudent thing for the homeowner
to do is replace all the original cloth covered wires in his conduits
with new conductors...

~~ Evan

On May 28, 1:11*pm, Evan wrote:
On May 28, 10:36*am, Smitty Two wrote:

In article ,
*"Stormin Mormon" wrote:

Time to consider rewiring the entire house. Cloth
insullation not been made for many decades, that stuff has
to be ancient. Will be more problems.

My brother lives in the house in which I grew up, built in 1916. Still
has the original fusebox in the basement, pushbutton light switches
throughout, and none of that silly ground plug or GFCI nonsense. Plenty
of 100 yr. old houses that don't have electrical problems.

Ah, but for whatever reason *this* OP's old house with the old
cloth covered wires has experienced something which is
indicating that it is getting close to the time to remove ALL of the
old wiring and replace it with conductors whose insulation is
not compromised and unsafe... *Whether this degradation was
the result of the *lottery winning* history of weather which
dried out the insulation over time, due to past overloading of
the circuits or poor workmanship in the original installation
is as yet unknown and may never be known...

However in this situation the most prudent thing for the homeowner
to do is replace all the original cloth covered wires in his conduits
with new conductors...

~~ Evan

I seriously doubt his ancient cloth covered wire, if indeed that
is what he has, was run inside conduit.

On May 28, 1:05*pm, Evan wrote:
On May 25, 11:44*am, "
wrote:





On May 24, 12:17*pm, Evan wrote:

On May 24, 8:10*am, "
wrote:

On May 24, 3:23*am, Evan wrote:

On May 23, 3:38*pm, "hr(bob) "
wrote:

On May 23, 11:55*am, "John Grabowski" wrote:

What could cause conduit to arc where it touches another conduit? How
can this happen without the conduit being charged with 110V?

A few months back, I added two AFCI breakers and a new house ground
wire in a home improvement project. A licensed electrician installed
the breakers and made the box connections. I assume he did it
correctly.

Here’s the problem:

I installed a basement HVAC duct touching an old metal flexible
conduit. A few weeks later, I noticed arcing between the conduit and
HVAC duct where they touched. Neither of the two shocked me when I
touched them, but sure enough – an orange arc was making a little
noise. Upon examination, the arcing had welded holes in the HVAC duct
and the conduit.

I snipped & dissected the conduit. The wire sheathing inside were fine
– one was a bit darkened. Over a few weeks, I expected much worse. Oh
well, problem solved. Maybe it was HVAC static discharge.

But then yesterday, I heard the same noise inside a kitchen light
fixture on a different circuit. The box was hot to the touch. Upon
dissection, however, nothing in the box was damaged.

HOWEVER – that box’s conduit was touching another conduit, and sure
enough – a little hole had been welded where they had been touching.

What could be causing this? I am a little spooked.

*My first thoughts are that a neutral wire is touching something or is
broken and the conduit or duct is being used as the return. *My other
thought was that maybe there are some grounding (Or lack of) issues and the
conduit or duct is some how energized. *However you did mention the
installation of a house ground wire. *Was a new ground rod installed? *Are
all of the pipes bonded? *How old is this house?

When this is happening, put an ammeter on each of the ground wires in the
circuit breaker panel to see if any are carrying a load. *Then check the
loads on the neutrals and compare the readings to the respective hot leg for
each. *You could also try putting the ammeter around the metal conduit and
see if you get a reading.

You could also use a voltmeter and check the volts by touching one lead to
the metal conduit and the other to a water pipe (Assuming the water pipe is
grounded properly).

If you paid the electrician, was he licensed?? If so, I would call him
up asap and tell him there is a problem relating to the recent work
and demand (politely that )he come out and at least look at it. *If he
finds a problem unrelated to his work, then you have to pay $ to get
it fixed. *If it is related to his work, he should fix it, if he
resists suggest that you might be in touch with whomever licenses
electricians where you live. *THIS IS POTENTAILLY LIFE-THREATENING!!!

Umm Bob, it is quite possible, even likely that the arcs the
OP is posting about are happening on circuits other than
the ones the licensed electrician worked on...

@OP:

The arcing between the HVAC duct and the flexible metal
conduit is one of the reasons why code compliant electrical
runs should not be in contact with other metallic objects like
HVAC ducting or copper plumbing lines or black iron gas
lines... *

You have a reference where it says that in the code? *If so,
there must be a hell of a lot of illegal installs. * A typical
example would be a furnace where metal conduit was
used to run power to the furnace and the the conduit
is fastened with metal clamps directly to the furnace
housing along it's run and to the metal connection box.
That in turn means that the entire metal duct system
is connected to the metal conduit. *So is the metal
gas pipe connected to the furnace and everything
connected to that piping system.

When connections in the circuit open or were not
correctly installed to begin with those other metal utility
pipes or ducts can become the return side of the circuit
and cause arcing/fires/electric shocks...

I would install a proper run of flexible metal conduit which
does not physically come in contact with your HVAC
trunk line possibly even using a non-metallic sheathed
type of wire or raintight (vinyl coated flex) flexible conduit
for the run from point to point where it passes by your
HVAC duct if you can not reroute the run so it doesn't
physically touch the metal ductwork...

If wiring were done that way, there would sure be some
strange looking conglomerations out there.

As far as the other problems you mentioned in the boxes
with the conduit, you definitely need a qualified electrician
to come out to your house and completely trace all of the
circuits which are displaying this arcing behavior to find out
where the wiring is damaged or where the incorrect
connection is located so that it can be properly repaired
so as not to arc anymore and not be a shock/explosion
or fire hazard any longer...

From what I've heard so far, this is his only real problem.

You might be looking at pulling new wires to fix some
mystery problem somewhere but doing that is cheap
compared to having to deal with some sort of electrical
fire...

~~ Evan- Hide quoted text -

- Show quoted text -

As far as the code cite: *I don't know chapter and verse,
but the basics of the code not allowing wiring to be in
physical contact with ductwork is that the ducting can
move around as the HVAC system operates and duct
pressure rises and falls and cause mechanical damage
to the wiring over the course of time... *All wiring runs MUST
be installed so that they are protected from mechanical
damage... *

Which the metal conduit that he has that you objected to
provides.

It goes more to that specifically and the general
phrase "all work must be done in a workmanlike manner"
which is something that looms over all electrical installs...

Maybe workmanlike means to you that metal conduits or
raceways can't be in contact with any other metal like
an HVAC duct, but it doesn't mean it to me, nor does it
say it anywhere in the code I am aware of. * *I can show
you new installs of HVAC that passed inspection here
where conduit is touching metal or fastened directly to it.
In fact, NEC allows metal conduit to be used INSIDE
HVAC ducts. *So, it's hard to imagine they have a
prohibition against a metal conduit touching metal
like an HVAC duct anywhere along it's run.

I have forgotten how much clearance must be afforded for
wiring runs near other utility lines but I know for a fact
that there are different rules for clearances depending
on whether you are running the wiring parallel to some
other utility line or perpendicular to another utility line...

When you figure it out, let us know.

I am not a practicing electrician who does wiring in new
homes every day, I do maintenance on existing installs
in commercial buildings and trust me, I know that there
are quite a few code violations out there in otherwise
normal looking buildings because it is sealed up in the
walls or way above a ceiling where an inspector never
looked when signing off on the permits...

I suspect some of the things you think are violations are
in fact not, as is the case in point. *You;d have the guy
rewiring his conduit runs, when there is no need to do
so. *The only problem in evidence is that current is
flowing in the ground path and that is what needs to
be fixed.

I agree with the theory that there is an open or misconnected
neutral somewhere in the OP's house which is now using
the HVAC ductwork and the arcing conduit as a return path
which is very dangerous and could cause a fire... *I don't
think it is in any way connected to either of the circuits he
had the electrician install the AFCI breakers on because
those breakers would be tripping if the amount of current
going out on the hot didn't match up with what was coming
back on the neutral -- it is what such breakers are designed
to detect and open the circuit to prevent...

~~ Evan- Hide quoted text -

- Show quoted text -

There is *NO* code approved way to "repair" cloth insulated
wires which have degraded to the point at which they are
throwing arcs that involves anything less than pulling new
conductors...

I never suggested there was. And IU don't see that having
anything to do with my comments. But now that you've brought
it up, let me point out this. He only indicated that there was
some cloth covered wire inside a box connected to a
fixture. For all we know, it could be the FIXTURE wires
that are the problem. And that could be solved without
rewiring the house.





*Wrapping conductors with old degraded
insulation in black electrical tape only resolves the symptom
of the actual problem where it is most accessible, it does
nothing at all to solve the problem and eliminate the KNOWN
risk of fire that exists from old conductors which were
observed arcing...

Whom are you replying to? I never suggested wrapping
anything in electrical tape.