Toto shower valve with threaded adapter

Hi. My first post here. I'm replacing an old shower valve with a new Toto valve. It's threaded for adapters. The instructions say to use teflon to secure the adapter to the valve and solder the piping to the adapter.

My question is about order of operations. Do I solder the adapter to the pipe first and then thread the adapter onto the valve so I don't melt the teflon? Then I would have to solder the T on the supply after that because of the obvious turning to connect the adapter.

Is my thinking correct?

I've seen tutorials that say you can assemble the whole thing and then solder everything at once, but that doesn't make sense, but then again, I don't have experience with soldering.

As a side question (or potential option for part of the install), could I use sharkbites that are threaded on one end and take the 1/2" copper on the other? I wouldn't use the sharkbites for the spout, but seems logical that I could use it for the two supplies and shower head. However, I'd prefer to solder.

thanks,
Justin

I would keep the heat away from the valve. Sweat the adapter to the pipe then thread it in.

While SharkBites could be used bear in mind they also allow the pipe to rotate within the Sharkbite.
Part of a good installation of a shower mixer is having it well secured in the wall.
Rigid sweat connections do a lot for this....

I would remove the valve's mechanism and then solder the adapters to the valve, thus eliminating any possibility of a thread leak, for any reason. But if I were going to just screw them on, I would NOT use tape, since I am not one of the devotees of tape on metal threads.

Does the teflon melt on your frying pan? Not to worry about that issue. Now, for ease of soldering, if you could solder a shortish pipe into the adapters, then screw them into the valve, then solder couplings or elbows in place, all of those joints are more "friendly" than soldering to an adapter already screwed into the valve, and also the valve body and internals are protected.

Redwood, yeah that's why I think I want to sweat them on. Though it's unlikely the supply lines would spin because they will have the 90 degree elbow in them and I would secure the valve to blocking.

HJ I thought about soldering the threaded adapter in. I had read on this forum that some people do this and some people are leary. As a beginner solderer, are there any extra steps to take when soldering threads? Why don't you like to use tape on threads? Are you exclusive about it, or just when it's getting closed up behind a wall?

Jimbo, good point. I wonder if the Teflon tape has any other ingredients that differentiate it from a frying pan that could melt? Thanks for the suggestions about how to use the junctions to make the install easier.

I'll be working on it today. And will report back.

Teflon Tape contains only Teflon and is good to about 500 degrees F.
Solder melts about 400 degrees F so yes a noobie could get into overheating the Teflon.

If you do solder the threads of the adapter to the valve body I would remove the internal components to prevent damage from overheating.

It really isn't necessary to solder those threads. I use tape and dope and haven't had a leak in as long as I can recall...

Having done this a few times before now, I would solder the pipe to the adaptor first, then use tape and joint compound to attach the adaptors to the valve. Do them up tight.

Then use solder couplings, like Jimbo said. Watch very closely for leaks using a light and a mirror: it can be very slow. If it does leak - unfortunate but it can happen - drain down, cut pipe, tighten some more and use another coupling.

This way you keep the heat away from the valve.

thanks all,

well I installed it today. I decided to solder the threads, mostly because I was curious. I installed the adapters finger tight, then gave it just a tiny turn with the pliers, then soldered. Some of the joints were less than pretty, I used too much, but it doesn't leak. One thing I was curious about was how do you guys set the depth of the valve to be in plane with the finish wall. It seems like it would be easiest to mount the valve to blocking so it's right were you want it, but don't most plumbers just use the rigidity of the copper pipes to keep the valve in place? When mine was done, I have to apply forward pressure to get it to the correct position.

Justin

Blocking is best. I suggest you temporarily install the trim and actually check how it fits. Some people like it at different depths that the manufacturer suggests.

jimbo said:

Does the teflon melt on your frying pan? Not to worry about that issue.

Click to expand...

Teflon will melt and there are several types of teflon with several different melt points, typically in the 500 F plus range. One of my early projects was diagnosing why a reactor's welded teflon liner failed. Our Maintenance blamed our Operations, Operations asked me to determine the cause of the failure. After a bit of researching, studying the reactor temp excursions on the strip charts, and examining the melted sections I concluded that a lower melt teflon type was mistakenly used in the hottest portion of the vessel (melt point difference of the materials was about 15-20 F if memory serves.) The chemists confirmed it spectroscopically, the supplier denied it at first...but eventually admitted that it was possible someone pulled teflon from the wrong roll in their shop while fabricating. Maintenance and Operations were happy since neither of them was responsible for the quarter million dollar mistake, and it never happened again.

quote; I installed the adapters finger tight, then gave it just a tiny turn with the pliers, then soldered.o

If you did NOT put flux on both threads, then you did a poor soldering job. If you did use it, then the joints should not have looked "ugly", regardless of how much solder you tried to use.

Yes, I did use flux on both the fittings and the pipe. A few joints just had big goops of solder is all.

Indian jewelry. How delightful.

I measure my solder to avoid that. But people here disagree with that approach.

There's nothing I like more than a neat joint.

The solder should have flowed the same as with a copper joint, and any "gloop" should have been "wiped" off