[wumphress]

I have a Kohler shower valve and transfer valve, the transfer valve has male threads for connections. I'm wonder if I start with the female adapter doped up and screwed on it will melt when I sweat the rest of the pipes together? I could sweat the adapter with a short nipple first then screw it onto the valve, but I'm not sure how long of a nipple would do to get it far enough away as not to melt the pipe dope when I finish connecting to the half inch copper supply lines.
Thanks in advance for any help you can provide
William Umphress.
[email protected]

[hkstroud]

I have to make several assumptions here. I assume that since you posted this question on the construction page and not the plumbing page, you are not experienced in plumbing or sweat soldering pipe. I also assume you are speaking of an normal Kohler tub and shower valve. Final assumption is that the fittings you need to use must be 90 or 45 ells, otherwise you would not need fittings.

First, the pipe dope is a lubricant not a sealer. It purpose is to aid you in tightening the fitting, not sealing the joint. Once you have tightened the fitting it has done its job.

Second, you said the valve has male threads. Look at the inside of that connection. Is the inside smooth and polished, will a 1/2" copper pipe fit snugly inside? If it will, chances are that the valve is designed to be installed using a female adapter as you are attempting to do or by soldering a pipe directly to the valve. That means that the valve can withstand the heat of soldering. This is a common way of manufacturing a valve.

If you use the female adapter, solder it to a length of pipe longer than you need. Screw the adapter and pipe to the valve. Install the valve in place. Cut the pipe to the length needed. Flux and install the ells. When soldering, heat the fitting not the pipe. Direct your flame to the under side of the fitting, when the flux liquifies touch the solder to the opposite side of the fitting. When the fitting is hot enough, the solder will melt and run around the joint. When the solder has run completely around the joint, STOP. Applying any more will only cause the solder to run inside the pipe to later block your valve. When making upside down vertical joints, I like to make the horizontal joints first, then the vertical joint. Solder is drawn to the heat of the fitting. Making the horizontal joint first, insures that fitting is hot enough to quickly make the vertical joint.

After installing the valve remove the valve cartridge and flush the pipes to remove any loose solder or debris that might be inside. Reinstall the cartridge.

If things are not as I have assumed and you are stilled concerned about soldering close to the valve, remove the cartridge or stems and then do your soldering.

P.S.
If you are soldering close to a wooden member, get a piece of aluminum foil, fold it about four times. Stick it to the wood with a thumb tack. Makes a nice heat shield and you don't scorch the wood.