Ideas wanted on how to thaw a water pipe inside a wall?

Your pipe has to be copper for this to work.

Shut off your main valve coming into the house.

Open a valve (faucet, shower) in the highest place of the system (at least one to prevent build of steam pressure, more if you have them). Find a section of pipe that is away from everything that burns and near the lowest place of the system. Put a torch flame on it. This is assuming that there is water in the pipe. As long as there is water in the pipe, the pipe will get hot but not burn anything. It would have to vaporize the water first and empty it from the pipe. The advantage here is that copper is a very good conductor of heat. As the ice melts, it will drop to the lowest place of the system, thereby maintaining adequate water on the section of pipe that you are heating with a torch. It will take time, and if the zone you are working in is below freezing, then it will take even longer.

The pipe has to be away from the wall (rarely) or you will burn your house. A heat shield can be made from a food can or aluminum cake pan. It wouldn't hurt to put wet rags behind the shield for the same reasons explained above.

Steam (or sputtering water) coming out of the open faucet means you have cleared the line enough for water to pass.

If the pipe burst from the freeze, then you will have a water leak when you turn the main back on. Have someone on standby at the main. Some mains don't shut off very well either. Open a low valve in that case.

We had almost the exact same thing the day before yesterday. Only we could get to the pipes from the landing in the stairway. We already had a hole cut there from having trouble during the summer and "thought" we had to replace a pipe. But, since the hole was there, we thought why cover it with wall again if we need in there. We bought cabinet doors from Lowes and put over the hole. Anyways, we got to ours like that with a blow dryer and it was open in no time. Hope this helps.

when it gets that cold, crack open the fauce nearest to that pipe, just a tiny bit ,so it drips, moving water will not freeze. I would suggest going through the trouble of taking a small piece of sheetrock out to access the pipe, wrap it with insulation and replace sheetrock. If the pipe bursts from freezing, which it is likely to do, you will have alot more work ahead of you than just insulating the pipe. You can also drill a small hole in the wall next to the pipe and squirt foam insulation into the stud bay. You can buy expanding foam insulation at Home Depot or most hardware stores. It is a product by the name of Great Stuff. by the way a stud bay is the area inside the wall between two studs.

There is very little you can do. Last time it happen to me I just turn on the cold and hot water taps. increases the heating of room adjacent, and wait. It started very slowly but in 20 to 30 minutes both hot and cold water started to dripping. Also insted of blowing air to the whole pipe, just try to blow the air dryer into the closet space of tap.

I hope that work. Good luck

You need a plumber with a pipe thawing machine.(like a welder,they clamp it on top and bottom) If it's split you will have to open the wall to repair it.. While you are in there insulate the hell out of it..Stop any and all holes that air can get through...

Small space heater, you might want to cut that hole cause if the pipes blow your gonna have more problems than you want...

SET UR HOUSE ON FIRE