I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?






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On Apr 1, 10:44*am, The Midnight Gardener The Midnight Gardener
wrote:
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?

http://midnightgardener.blogspot.com

without knowing specifics, I would probably pull all the old wiring
out save for one conductor, then use that to drag the new wiring
through. If it pulls hard I'd pull the last conductor out pulling a
pull string, then use the pull string to pull the new wire through.

nate

On Apr 1, 7:44*am, The Midnight Gardener The Midnight Gardener
wrote:
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?

http://midnightgardener.blogspot.com


The good news is that the run is only 25 ft. The bad news is
"several 90 degree turns".

I would attach a wire pulling chord (~3/16") to the existing wires &
then pull out the old wires.

Do not just yank out the wires & plan to use a fish tape; take
advantage of the fact that the conduit is already filled.

Attach the new conductors to the wire pulling chord. Squirt some
wiring pulling lube into the conduit & install the conductors.

A 25 ft run is pretty short but wiring pulling is always easier with a
helper who can push while you pull.

A helper is useful to get the wires going into the conduit without
trouble or damage.

cheers
Bob

The Midnight Gardener wrote:
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?
....

Left out most important part besides what others already said -- what
size/number of existing and proposed wires? What type of conduit?

You'll undoubtedly need to lube the new when pulling it, too. How easy
it will be to pull the old will be very much dependent on what is there
and how the run actually goes and what condition it is in underground.
A lot there will depend on how long it's been in place.

--

first of all tie a pull string of sufficient caliber to the old wires and
pull them out.,

then get single strand wires in the gauge you need.

tie them to the string. Use copious amounts of wire lube at the point of
entry before starting AND during the pull.

have two people. one pushing and feeding, and the other one pulling the
string.

It's gonna get tough if you have over 360 degrees of bend. That is the
normal limit for pulling through conduit. BUT with enough lube and
patience, you shouldn't have any problem pulling 3 or 4 conductors up to 8ga
through a 3/4" conduit.

steve


The Midnight Gardener wrote in message
news
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?






http://midnightgardener.blogspot.com

On Apr 1, 10:44 am, The Midnight Gardener The Midnight Gardener
wrote:
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?


It's gonna depend a lot on whether they used sweeps or nineties.

Steve

On Tue, 01 Apr 2008 07:44:53 -0700, The Midnight Gardener The
Midnight Gardener wrote:

I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?


Pulling the wires out one at a time will probably be hard to do.

The most practical way would be to pull out the old wire with a string
attached to the wire. Use the string to pull in a pull rope that
would be reusable.

Pulling out the old wire will give you a chance to measure the length
for the new wire.

Don't forget to use wire soap. It really helps one person is pushing
on the wire while the other is pulling. 1,2,3 pull 1,2,3 pull

There is a limit to how many wires you can put in a 3/4 pipe. I am
guessing that because the existing pipe is in concrete you may find
out what that limit is.

I am not sure what the record is. Let us know.

The Midnight Gardener wrote in message
news
I need to fish some 240v wiring as follows: From the breaker panel
into an existing 3/4 inch conduit that goes vertical umtil it hits the
ground. Once in the ground it nakes several 90 degree turns until it
comes back out of the ground about 25 feet away. A great portion of
the underground run is in conduit that is under concrete. There are
wires in the conduit now but they are the wrong guage for what I am
trying to do. What is the easiest way to remove the old wiring and
then run new wiring without tearing everything up?






http://midnightgardener.blogspot.com
I would try to blow any debris out of the conduit and blow some liquid
wire-lube thru it. Straighten the wires carefully, trim some of the
insulation and perhaps some of the wire strands off. Make a secure
connection (not too big) to a substantial rope or electricians snake and
pull the old wires out. Attach the new stranded wires, lube good, and pull
them back in.

Evaluate the sizes of the conduit, the old wires and the new wires carefully
before you start. Be really sure about the size and strength of your
connections also. If it jams, it will likely be at the connections. Once you
start the pulling you are pretty much commited and if anything jams or comes
loose you could be in real trouble. If at all possible, at least seek the
on-site advice of someone with wire pulling experience to advise you.

Don Young

On Apr 1, 11:55 am, "S. Barker" wrote:
first of all tie a pull string of sufficient caliber to the old wires and
pull them out.,

then get single strand wires in the gauge you need.

What is a "single strand" wire? You mean solid wire, or stranded
wire?

Single strand would seem to mean solid.

I have always found stranded wire easy to pull, but impossible to
push. You?

JK

On Tue, 01 Apr 2008 13:58:35 -0500, Terry
wrote:


The most practical way would be to pull out the old wire with a string
attached to the wire. Use the string to pull in a pull rope that
would be reusable.

If you have to pull out the old wire, and you do, wouldn't it be a
good idea to solder the new wires to the old wire?

That way you wouldn't have to worry abou tthe pull string breaking, or
coming loose from the wire.

Or you could do both if you wanted. Solder the wires and also pull
the pull string through. I assume the string (nylon?) won't be very
thick and will go through easily. If the wires go through on the
first time, you can leave the string in place in case you need to add
an additional wire later.


Pulling out the old wire will give you a chance to measure the length
for the new wire.

He should be able to estimate pretty well, and how hard is it to have
10 or 20 feet extra just in case.

he will have to be certain the old conduit is large enough for the new
larger wiring gauge......

since theres no reason to thiner wiring.....

even worse if he needs to add another conductor, like a real neutral
plus ground..........

Thanks for ll of the good advice everyone. This is going to be one of
my honetdews in the coming weeks. The wires are for a spa that someone
gave my wife. I wish the thing would just go away!






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