Joe J wrote:

A house we just moved into has two identical Kohler faucets. The one
for the MB shower stall sucks for temperature regulation. It can
sometime take 3-5 minutes to get the temperature correct, with the
slightest movement of the single handle faucet creating dramatic temp
swings. The other one in the other bathroom, tub/shower works fine.
Would changing out some of the inner parts help this? Changing out
the faucet is not possible w/o tearing out an entire linen closet.
Estimated age of faucets is 17 years.

Thanks,

The pressure balancing mechanism inside the Kohler shower valves is
replaceable, and (in my case, given that I had the original receipt
from 11 years ago) a no-cost, warranty parts shipment direct from
Kohler.

The mechanism does develop internal leaks which make the valve
mis-behave exactly the way you describe. Two rubber diaphragms (one for
hot and one for hold) are actuated by small ceramic plungers, and they
eventually wear out, leaking the hot into the cold, and making the
control no longer possible.

The repair procedure takes about an hour from start to finish, and is
not particularly difficult except that there is a twisting required to
un fasten the valve mechanism which is not especially obvious. The new
replacement pressure balancing valve (PBV) comes with installation
instructions as far as I can recall. Also, the Kohler website has a lot
of useful data including exploded parts drawings, descriptions, etc.
Kohler recommends and provides "plumbers grease / silicone grease" to
lubricate the replacement PBV and seals, and I would strongly suggest
getting some extra at Home Deport or Lowes. The tiny capsule they
provided was not even remotely enough since it took me (an amateur
plumber) several attempts to get the PBV to properly seat with no
leaks. The grease Kohler provides gets used up the first time you try
to install it.

Good luck.

Smarty

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