Couple of questions for you. There is nothing in your page about your qualifications. Are you a licenced tech ? If not,and you are working in a public building, a very serious liability issue if anything happends. Your kids kids will die of old age before the law suet is payed off. Compression fittings in hot water heating is an absolute NO - NO. As in emergency heat to keep things from freezing they might cut you some slack but you had better get a qualified tech in A.S.A.P. to make the repairs permament. Without seeing your pipe it could be stainless steel ( i dought it )aluminum, galvanize, or tin plated copper. If it won't take solder it could be steel.You need a special flux. Actually on second thought i'd dought it is aluminum. It would have melted before your silver solder would have. Good luck and hope to hell nothing happends before you get a permenant fix.

"In the end, I would make the decision based on the estimated risk the pipe becoming energized." Chris, There is legitimate discussion about the need to bond the hot water to the cold at the water heater since until recently it was connected by other means and it isn't specifically called for in the NEC. Your statement that "They probably already are bonded through a shower valve in the house" leaves open the possibility that they aren't - which is the whole point here. Bonding is not the same thing as using the piping for a grounding electrode. The NEC is very clear that all piping must be bonded to the electrical system. It's not an option to decide if you want to bond the piping to the electrical system. Most certainly you don't get make a decision that "you don't think it will become energized, therefore you aren't going to bond it" as suggested by your last sentence. Think of the implications if an un-bonded water pipe comes in contact with an electrical wire and then you go to take a shower, or do dishes, or any number of other things. If it's bonded to the electrical system, it causes a breaker to trip. If not, everything it touches is energized.

Homebound_ in regards to the non-descript flame characteristics of the TS-4000. If we examine the flame in a common propane torch we see a very descript teardrop shape inner flame, surrounded by a pale outer flame. If you will look down the bore of your TS-4000 burner tip you will see a flat disk that has 6 slots and each segment is then twisted slightly forming a pitch similar to propellar blades. Not only does that diverter increase the swirling effect it also divides the flame into 6 separate but equal flames. Now try this experiment. Pull the trigger and light the flame, then very slowly release the trigger a bit and you will see the flame drop down a bit. With the trigger only slightly depressed you will actually see the 6 points of flame are very distinct but when the trigger is held fully open all six points blend together in what appears as a flat top on the inner flame. In regards to wiping the joint with the flux brush. Many plumbers do that to insure their is a clean line of solder all the way around the joint however I have two reservations against that practice. 1. Wiping a hot joint with the flux brush results in burning the bristles in the brush. When the brush is then placed back in the flux it tends to contaminate the flux with carbon and burnt bristles. 2. Plumbing Flux is acid based and should be wiped off the joint while it is still warm. I prefer to wipe the joints with a clean damp cotton cloth. Coolvt asked about refilling the small cylanders from a larger tank. The reason you cannot find an adapter hose to do so is easy to explain, it simply would not work. Propane is a liquid which boils to a gas before leaving the tank. In order to refill the tank you would need a compressor system similar to a refrigeration compressor to compress the gas to the condensing pressure in order to refill a tank. (While the actual pressures are different the handling characteristics are the same as handling a refrigerant and in fact, propane is listed as a refrigerant.) By example at 30degF the temperature of vaporization of Propane is 30degF while at 70degF it is 128psi and at 110degF it is 197psi. While it is not really prevalent on the small tanks used for hand torches if you have a propane grille you will often see a frost line forming on the outside of the tank after the burner has been burning a while. That frost line on the exterior of the tank is a visible indicator of how much liquid propane is left in the tank. Diyourselfer stated that they now have the TS-8000 out so maybe he should buy that one. I really can't comment on the TS-8000 simply because my old TS-4000's refuse to die...LOL. I bought my first TS-4000 in 1985. About 6 years later I was connecting water lines to a condensate return tank in a boiler room and accidently dropped the torch in the tank. When i fished it out and shock it off the ignighter was not working. I managed to manually light the flame and continue my project. The next day while at the supply house I grabbed a new TS-4000 to replace the original one then a few days later i was in an ACE Hardware store and discovered that they carry a full line of replacement parts. I grabbed a new ignighter assembly and the original was back in business. In fact, that 1985 model is still in the top of my tool box and working fine. Last year someone gave me a new TS-4000 for Christmas and it sat on the floor beside my desk for months, occassionally being used as a cigarette lighter...LOL. One day the pilot went out on the water heater so I went to gtab my torch by the desk to light the pilot and the torch was gone. I asked my wife if she knew where it went and she replied,"Yes, I have it in the kitchen and I am keeping it there!" I said, what do you need a propane torch in the kitchen for" and was i amazed at her reply, She says, "I use it when i am making pies. I saw a chef on a TV cooking show use one to brown the peaks on the lemon marangue pie topping so I tried it and it works great. If you need a cigarette lighter I will buy you one, but I am keeping the torch!"

I have to amend my view of failing joints. Today my neighbor called and asked how to shut off the water to the house because she thought she had a leak in the garage. When I took a look at what was going on, I saw that she had a frost free hose bibb in an unheated wall and there was a length of copper pipe that extended from that to a coupling. the copper pipe was showing about 1/2" of shiny solder. I can only theorize that it froze when we got down to 15 deg F last week, it was a bad joint, and the ice forced the pipe out of the coupling, but not completely. Surprisingly, the joint was only dripping because it hadn't totally failed yet. She had her plumber come over to cut out the joint and resolder everything. When I asked him how often he'd seen something like that, he said it was the first time...and he was at least 50 years old.