View Full Version : ball valve blew up
GregO
09-14-2008, 04:57 PM
Installed a new water heater yesterday and had an unbelievably slow leak coming from a brass ball valve/copper connection - cut out the offending valve and, for fun, tried resoldering it to see if any more solder could have been taken up.
Nope! Solder kept melting and sliding off the pipe without anymore uptake. And eventually...BOOM! Sounded like a gunshot coming out of the pipe (~10" assembly including the ball valve). Blew the nylon seal out of valve. Had never done that before, but it was interesting.
Greg
Gary Swart
09-14-2008, 05:14 PM
I'll let the pros comment on why the valve blew up, but I can tell you why the solder didn't take. What makes solder draw into a joint is flux. Once the flux is gone, to add solder you must disassemble the joint completely, clean it so they will fit back together. Then start over with flux, heat, and solder. Anytime water seeps through the joint, I can not be just resoldered.
The valve blew up because there was water trapped inside around the ball. First it became super saturated steam, and then when the pressure reached the proper point, it exploded, just like a water heater will except on a much smaller scale.
Redwood
09-14-2008, 06:34 PM
Its a good idea to sweat with the valve in the open position...
nhmaster
09-14-2008, 07:05 PM
Just one of the hazards of plumbing, except you don't get the purple heart.:D Next time leave the valve open when you heat it up.
rombo
09-14-2008, 07:21 PM
Your lucky you didn't get that valve or the steam in the face you could of killed your self:eek:
When soldering the pipe won't come up to sweating temperature unless the pipe being soldered is purged of water.
If a copper joint leaks as others said the proper procedure is to disassemble the joints sand the ends of the pipes. Using a wire brush clean out the fitting or valve apply flux and resweat.
If you blew the ball valve then the pipe definitely had water in it and yes as the others said it's best to leave any valve open when you are soldering both to reduce the chance of heat related valve damage and to prevent the situation you had.
GregO
09-15-2008, 05:50 AM
There's some misunderstanding here...
The ball valve was open - in addition, I tried resoldering that joint only after I cut it out to test. In the past, I've added flux to external joints and have had them "wick" some small amounts of solder, but this was simply experimental, and like I said, interesting in that it was a 10" loose section of pipe cut away and heated with the valve full-open.
Greg
When soldering the pipe won't come up to sweating temperature unless the pipe being soldered is purged of water.
If a copper joint leaks as others said the proper procedure is to disassemble the joints sand the ends of the pipes. Using a wire brush clean out the fitting or valve apply flux and resweat.
If you blew the ball valve then the pipe definitely had water in it and yes as the others said it's best to leave any valve open when you are soldering both to reduce the chance of heat related valve damage and to prevent the situation you had.
GregO
09-15-2008, 05:52 AM
Your lucky you didn't get that valve or the steam in the face you could of killed your self:eek:
To your point, definitely keep your face and other parts away from opened pipe ends just in case...:):D
Enen when the valve is open, there is water inside the body outside the ball. If it is half open, then the water can boil away without become superheated or building up destructive pressure.