Soldered Pipework - Threaded or Soldered Valve

[Chefwong]

When setting up access panels/shut off valve locations --- if you're laying in copper runs (soldered plumbing), for the shut off valves, do you go solder as well OR do you use a solder adapter/MIP with a FIP valve. Where in a threaded valve, should you ever need to move, change, etc --- the valve is reusable ?

I can see in the latter application where if it went straight solder, it would be a ~guaranteed~ leak tight connection.

 

[holowinko]

I would solder it, There is no need to change it to a male adapter and an IP ball valve.
As for reusing it, the cost of labor outweighs the price of a new valve.

 

[Sponsor]

 

[hj]

solder it. Who would be so cheap that they remove and reuse valves?

 

[Terry]

Solder it.
Anytime you work on old stuff and it's a valve, it should be replaced, not reused.

 

[Chefwong]

It's new work incorporating into old pipes.
New Shut Offs so that I can do work in the future without shutting the main down.

All copper solder....but I was thinking that the new valve would be threaded and I would but the adapter on it. It would also ~offset~ the distance on where I'll be putting the heat minimizing the heat on the valve. It's been awhile since I torched...and the last time I did, which were just a couple of angle stops, no valves/rubber were deformed in the process.

Thanks all

 

[Terry]

You can remove the handles while soldering.

 

[hj]

valve

quote; It would also ~offset~ the distance on where I'll be putting the heat minimizing the heat on the valve

I would hope it would be a "long distance" because you should NOT solder to the adapter once it is screwed into the valve.

 

[Chefwong]

I may have misworded it ?
Standard FIP on ballvalve.

If I use a MIP/Copper Adapter, fit all the copper and then solder the copper to the *sweat end* of the adapter, it is not recommended ?

 

[Chefwong]

Thanks Terry. Never dawned on me to remove them.....

 

[Terry]

Most plumbers, when using a threaded male adapter, will solder the adapter to a length of pipe, let it cool, dope it up and thread it into the valve. We like to see the next solder joint about 6" or more away and try not to let the heat make it's way back to the doped and threaded joints.

 

[hj]

quote; If I use a MIP/Copper Adapter, fit all the copper and then solder the copper to the *sweat end* of the adapter,

NOT if the adapter is already screwed into the valve. ANY male/female threaded connection should NOT be heated. The two threads will expand at different rates because of the slow heat transfer. What may happen is that the female which is on the "outside" will get hot first and expand away from the male thread which is expanding slower. Then after the heat is removed, the female may "shrink" faster but stop when it "squeezes" the male thread, but then the male thread may continue to cool and shrink away from the female a slight amount, which is when you get the leak, but it may NOT be a "visible" leak, but rather seep a small amount for years.

 

[Chefwong]

Thanks fellas for the great explanation.