On Saturday, March 18, 2017 at 9:11:32 AM UTC-4, Bill Gill wrote:
On 3/18/2017 7:22 AM, Joe Mayer wrote:
I have 120psi water pressure at my house and am having a hard time
getting a complete seal on the water connections of my tub faucet.
I had to use a couple of brass adapters to go from a 1/2" copper line to a
3/4" brass connection, so I have more joints than usual. I am using teflon
tape on all the joints and keep getting a little seepage around the joints.
The previous connections on the old faucet with 1/2" connectors were what I
think are called slip joints, using cone-shaped rubber washer. The brass
fittings do not have any kind of compression joint or washer to seal off
the
water, except on the end that connects to the copper line, where a
compression ring seems to be sealing just fine. The other connections
depend on the sealant on the threads. Should I be using permanent pipe
sealer at the threads that do not connect directly to the faucet and the
water line? Or is there something better than teflon tape that I should
use on the joints? I am wrapping about 2 layers of the teflon tape around
the male connectors, starting at the first threads of each joint.

Everybody immediately jumps up and tells you that you
have to have a pressure reducer. I have 120 psi water pressure
and have had hardly any problems. I have one hose bib that I
have a problem keeping washers in, but that hose bib is over
50 years old, and I suspect it just needs to be replaced.
So don't get in a swivet over people telling you what you
absolutely have to do.

As far as the leaks, you might try using the liquid pipe dope.
Put on a good thick coat and screw the threads up tight.

Bill

You will note that I mentioned fixtures in my response. I acknowledged
that the OP was have problems with his fittings, but I did not say that
the 120 PSI was the cause of the problems.

My point was that 120 PSI pressure can cause problems with many fixtures,
from toilet fill valves to washing machine solenoids.

If this site is correct, then the Uniform Plumbing Code requires PRV in
specific situations.

"The Uniform Plumbing Code and PRV

The Uniform Plumbing Code requires a PRV be installed if the water
pressure exceeds 80 PSI at the time the home is built, or for any
inspection of a plumbing task that involves a water test thereafter
resulting in high-pressure. "

http://ogradyplumbing.com/blog/under...ater-pressure/

If a PRV is required at 80 PSI for new builds and inspections, then
a PRV makes sense in *any* situation where the pressure exceeds 80 PSI.

One could argue that in older homes, a PRV is even more important because
fixtures and/or fittings may not meet the more stringent modern codes.