On Oct 13, 6:19*am, wrote:
On Mon, 12 Oct 2009 20:01:40 -0600, "SteveB"
wrote:

I was taking a shower, when the water started a chattering noise, and the
spray was a pulsed spray. *This came on when the Moen twist dial was in the
same position for about two minutes. *I changed the dial, then returned it
to the original temperature position, and it did it again. *A little
adjustment of the dial makes it go away, but it returns. *What's this?

Steve

The overall water pressure in your house has increased. The chatter is
the anti-scald device trying to deal with too much pressure.



You need to install a water pressure regulator...

Or replace a defective one (BTDT)

and set it at around 50 psi.

Hopefully, it's preset. Mine was.

The easiest way to check and adjust the pressure is to buy a
water pressure gauge that has a standard garden hose fitting on it.
You can buy these ready made for about $15.

True (or less, I paid $12)

Screw it on to any hose bib to use it.

To *use* it, that's true, but *which* bib you use might depend on what
you want to check.

The hose bib at the front of my house is before the PRV and therefore
at street pressure.

The hose bib at the rear of my house is after the PRV and thererfore
at "house" pressure.

I knew my PRV was bad when they both read about 85 psi.

And yes, the chattering went away after I replaced the PRV.