While working near the dock I heard of the practice of thawing frozen water pipes using a welding unit. I was told all they did is crank it up and attach boths leads. How is this accomplished (safely).
The electric current through the pipe heats by I^2R and then melts the ice. I would not do that myself for a couple of reasons: (1) it's hard to control how fast this happens and suddenly you get steam and BOOM -you've busted a pipe; (2) it's hard to know what part of the pipe is how hot and you may wind up with a fire.
My recommendation is to eliminate the condition that froze them in the first place, then warm the room to 20C and wait.
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"Well, I've wrestled with reality for 35 years, Doctor, and I'm happy to state I finally won out over it." Elwood P. Dowd
If you have a welder that has output settings makes it easier. The trick is to space the leads far enough apart so that the pipe gets warm not hot. And to know what setting for the distance they are apart. Dump enough current down any conductor it will get hot thats why there different amp capacities on conductor size. Pipe just became you conductor. Just don't know how much until you fry it.
Have old hot melt dispenser that the used a welder to heat the hydraulic hose by running current down the braided wire.
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Cold Weather
Re: Cold weather
