Hello all, avid DIY'er and not afreaid to break anything at least twice, before getting it right, (HEHE)

Here is my situation(s)

1) In my master bath the shower has very poor cold water pressure. It's a single handle kohler diverter shower/tub. The cold water is almost non-existening. The pressure does increase as I adjust the water hotter. But that brings me to number 2.

2) When adjusting the water temp from hot/cold we get a high pitch squeal on the perfect hot/cold setting. If I move the handle either hotter or colder the sound goes away. But too much each way, you can't be in shower, because it's too hot or too cold.

This is the only bathroom out of three that has an issue. The sinks in the master are fine as well for cold and hot. The water supply is in basement about 20-25 feet from master (ranch home).

The boiler is olny five years old and we think works very good. The water conditioner works as well. The water pump is set at 45 psi.

The house is a 57 yrs old Ranch with copper piping.

Thanks

I suspect that there is a small piece of debris or something lodged in the faucet of the shower. I believe that the supply pipes are in good order because you have no other problems in this bathroom. There should be an access panel behind the faucet of the shower, and if the faucet was installed correctly, maybe some valves as well. I do not think the internal valves in the faucet will be sufficient. The entire faucet must be removed (you should get help with this for it is easier to remove if someone is inside the shower holding the faucet in place). You may be able to see and remove the partial obstruction and re-pipe the same valve in place without having to replace it (use unions instead of couplings to put plumbing back). You may also be able to flush the debris out by removing the shower head and rotating the faucet from hot to cold and back. I don't have much faith in this working, but it is easy to try and may save some headache.