On Fri, 11 Jun 2021 16:20:16 -0400, Ralph Mowery
wrote:

In article ,
says...

Sounds dubious to me. I can see it as a requirement if the shower/tub is being replaced,
it's a bathroom remodel, etc. But not if it's just that the old valve needs to be replaced.
And whatever it is, it's always up to the local or state authority that has jurisdiction as
to if it's OK or not.






I hate those one valve showers. Seems that the mix is often too cold
for me . Especially in the winter time where the incomming water is
much colder. I would rather take my chances of the water comming out
too hot. As long as you tell others in the house not to use the water
it is mostly safe.

You can go it and crank up the heat on those valves. You usually
remove the handle and rotate the plastic disk that limits the travel
or sets the balance. I just set mine up wide open and use the common
sense you were given.