My neighbors water main froze last week somewhere between the house and street. (200 feet) To thaw the pipe a contractor connected the leads from his welder to the shutoff at the street and the main coming into the house. New one to me. Any thoughts?

Years ago, worked for an apartment complex. Had pipes freeze all over the place one unusually cold couple of weeks. We used the welder too.

Hooked up with long cables and turned it on for maybe 2 seconds at a time. A little trickle would start and we'd pack everything away and let the flowing water do the rest.

Be careful since the house next door could catch fire. This was the subject of lengthy discussions some time ago where that was a reason for a code change.

I don't have the dates, but the proposal from Artie Barker former Idaho Cheif Electrical Inspector had his proposal accepted. I think it had to do with the bonding jumper around the water meter.

Glen -- can you researrch the 81 through the 87 TCR's or TCD's please.

E-Scott,
that's all the plumbers are doing in this deep freeze , they make a device that does essentially what the welders are doing.

, i have not investigated the 'bona-fide' device as yet,but believe high freq & skin effect is key & would venture sensitive electronics to be vunderable

The London Underground (two-thirds of which is actually open and at grade level) uses a similar principle of passing high-current low-voltage juice through the tracks to clear ice before trains start in the morning.

Have done that many times, isolate a conduit, hook welder leads at each end. Hook a air compressor on one end and stand back. When she blows you know you can pull out the bad and in with the new.
I have also used tubing and steam. Force the tubing up the conduit with steam coming out and you can break up a small iced in area.Blow it out and pull in new wires

Joe,

I have heard that before that electric fires have been started with welders and frozen pipes. There was an article in one of the magazines about it. Not sure if it was IAEI,EC&M, CEE, or EC. It is very common here in northern NJ to thaw pipes that way, the plumbers do it all the time. Can someone get a shock with this method?

How deep are the water services there?

had that done at my house about 5 years ago.i just called a welded to the house he hookup one end to the fireplug on the corner about 35 ft and the other end to my copper water pipe in my basement.now he did remove my water meter an put it back after.cost me 125.00 bucks,in fact he did 4 houses on my block that day.

that's the first time that i herd it can start a fire.anymore info on that.

ga.sparky56...about 3-4 ft down.some deeper

Our city passed an ordinance prohibiting the use of welding equipment to thaw frozen underground pipes after a fire was caused by this method. To make matters worse the fire was not in the house with the frozen water line. The plumber hooked up the welding leads to a fire hydrant and to the water line in the house. There was a nonmetallic under ground fitting in this water line. The current went from the water line to the service neutral (via the grounding electrode conductor) into the second house via the grounded conductor and to the water line in the second house and then to the fire hydrant. The water pipe grounding electrode conductor in the second house was run directly on a floor joist and the excessive current produced enough heat to ignite this joist. Fortunately this fire was discovered early and there was only a small amount of damage.
Don

Wow! 4 ft. deep or deeper? I'm glad I live in the south this time of year.

yeah ga.sparky56 here in north east wisconsin the main water line are buried 2 1/2 meters deep some case more but for run to the buldings the water dept call drop (the same terms what we electrican use) and they useally about over 1 1/2 meter deep and go in basement or stub up underneth of moble home park but for the rule for useing welder alot area are strict about it now most area say no way with le welder because most pipes are gone to plastic now that the princale reason they banned the welder pratics but some still do that and if not carefull it can blow the pipe i seeit happend with frozen vapour (steam) pipe !!!!!
merci marc

Sounds like to me,this method is not only a fire hazard but also boil water faster than a Ford flathead.

Have had it done at my folk's house several times by the municipal water dept when I was little. There was a curb box meter that they used for one connection and the other went to the incoming pipe in the basement. It can present a distinct fire problem depending on where the leads are connected and how the electrical system grounding and bonding is performed. The current doesn't care what pipe is frozen...just looking for a return path or paths! Somewhere I have an article about a fire caused by this process. If anyone want's to email me a FAX number I'll try to dig it out.

Joe,

I assume I'm the Glen.

Have not looked in any TCR's or TCD's yet.

The thawing may be in article 250 but don't know how a proposal would be appropriate.

Did researh the EC&M and the IAEI NEWS.

Their was a comment started in the August 1971 issue, which I can't find that issue now.

The November 1971 issue, on page 170, did have several readers address August issue of the use of welding machines to thaw frozen water lines. They all thought that where this is done, all grounded and grounding conductors must be removed from the dwelling wiring system and also any dwelling near by. One said a fire started in a neighbor's home and ruined some of the NM wiring of the homes .

In the the Oct 1972 issue, on page 106, 4 homes had fires in the Quebec area when using welders to thaw water pipes.

The November 1991 issue, page 64, melted the green wire out of the dishwasher cord and damaged the cord for the garbage disposal.

The April 1992 issue, page 63 to 66, had more than a page and one-half on this subject.

The July/August 1998 issue, pages 59 to 63, of the IAEI NEWS had 5 full pages of thawing a sub-divisions' water system had damaged a home.

******

Apparently, the risk of damaging the electrical systems of any nearby service connected loads is enormous, because of the network of metal underground water lines and the common grounding conductor of the utility.

Some damage may not become obvious for months.

Joe, I will try to look in the 250 articles of the TCR's and TCD's later on.

Glenn

Back during the blizzard of '78 my brother, who owns a welding fab/repair shop, and I wore out a Miller Roughneck portable welder thawing water lines on farms. The pipes don't actually get hot to the touch.
The dumb thing was, when it started warming up for a few days folks would stop letting their water trickle and when the frost line came back up they'd freeze all over again! Thawed the same lines 2 or 3 times that winter. We always made sure they unplugged all appliances before we started.

They were doing it in the 1994 freeze (i think it was), it lasted until April, or
at least the line to one of our barns was,
we fed the barn using above ground hose
connected fed from the house, to a laundry
hose connected to the hose bib in the barn.
We never did it ourselves, as almost all of our undergroud plumbing is plastic.

I have herd of the steam pipe method too, connect a long piece of 1/8" or so

Bump! Anyone having this same problem now?

Oddly enough, I stayed home yesterday to deal with frozen water pipes.

I am perplexed at these 'frozen water main' claims. I had three ice jams, and each was where the house branch line exited the ground (pipes are buried in the crawl space) and entered the crawl space.
la
You troubles don't happen when the pipes freeze; the problems happen when thawing water has no place to go, and the pipes burst.

Therefore, I consider the 'welder' approach to be a good way to burst a pipe, especially if there are any elbows in the run.

Instead, I chose to apply GENTLE heat to the 'downstream' side of the ice, after opening the line. For heat I placed one of those oil-filled electric radiator-type heaters near the pipe, and used a small fan to blow heat toward the pipe.

Slow? You bet- but I managed to clear all three jams without any broken pipes.

Prevention, of course, is better than repairs. My (first ever) freezing pipe problems were caused, in part, by the fact that my home is undergoing some major remodeling, and not as much heat has been leaking into the crawl space as a result. Ironically, the issues will be permanently addressed this Summer, when I have a complete re-plumb scheduled.

In the mean time, I have sealed the crawl space much better, and have rigged up some low-quality heat trace lines.

Although not personal, the Fire Dept responded to 10+ burst fire sprinkler issues.

I had to respond to a 5 story hotel; blown pipe on 5th floor...water all the way down to grade. Panels in first floor electric room in path. Another was in a condo bldg., three floors, six units affected. One at mall, sprinkler line in entry foyer area, nice mess, water in lower level gym.

More on the list for tommorrow.

The old hair dryer truck worked for me when it got cold back in my Michigan day. I did thaw out a frozen drain pipe in Fairbanks a few winters ago by cobbling a. Few brass fitting to connect to the sink faucet aireator and a long piece of 1/4" plastic tubing. I shoved it down past the trap till it didn't go no more and turned on the hot water. If the sink back filled, we scooped it out and went back at it. Eventually we had it open enough where the flowing hot water took care of the rest

Two hospitals in Hamilton Ont. where partially shut down do to burst sprinkler pipes. It has not been reported if it was do to freezing or not though.

Hadn't seen this thread before, but it reminds me of several years ago having the bright idea to use a welder to thaw the pipe between my house and garage. I instantly burned out the earth cable of the supply to the garage. Subsequently stuck to blowtorch or hair dryer for frozen pipes!