different spin...squeel in shower pipes/maybe fact?

that was suppose to say
Ok, so I know there's a lot of post probably on this topic but this has a slight difference to it...
I re-did the tile in my shower and took down the walls etc. I had a (way overpriced...400.00 for a 45 minute install)plumber come in and install a new facet, piping and shower head.

Before I had him come that shower never squealed ever! No matter what. Then I started noticing if water ran anywhere else in the house AFTER his install the thing would squeal a little for about 10 seconds. Well I just installed a new shower head that has a regular head and one mounted to a line. You can also turn them both at the same time...well of course this would create a similar pressure situation as when other water is running, so this baby is squealing like a pig when I turn them both on.

When I called to complain (as they said I had a warrenty)...they said they only gar. the connections and also since I provided the equipment (it was brand new though) they would not come back and fix it without charging me a min. fee of 59.50 + whateve cost to fix. Now she said they would refund if they found it to be there problem on the install, but if it a defective part (etc) it was mine they would not. Now I guess that's not a bad deal, but these people ripped me off once before, I don't want to engage in another situation where they say "your fault and here's the costs...you already owe me 59, do you want me to fix."

What could be causing the sound and what's the chances it's the part vs. bad install.

Any help is appreciated please.

$400 wow i need to become a licensed plumber.

assuming there is an access panel to the shower there is a couple things you can check your self.

Turn on the water and look at the pipes to see if they move. Could be as easy as installing some pipe clamps.

An even easier trick is to turn the water shut off valves a little bit to turn down the water pressure.

If that doesnt work there is probably something loose in the shower internals. if you are feeling ambishous you can try and take it apart to make sure nothing is loose but some showers dont come apart so easy.

Welcome PRB:
Squealing water lines are caused by a restriction, such as a pipe that was cut and not reemed, a little ball of glue in the line that has hit the shower faucet and is blocking enough to cause the squeal but not cut you off. Its the same principle you use with your lips to whistle; you pucker your lips and restrict the flow of air.
See if you can contact the state plumbing department and inquire about the plumber's work. I know, in Kentucky, the Department frowns on overcharging and our state requires all work to be warranted for a year.
Glenn

guyod and glennjanie...
thank you much for the advice...I will look into what you both said. This was exactly what I was looking for.

And that overcharge is an issue...I'm was furious when I saw how long it took...a man thinking he can charge 400 an hour for anything short of brain surgery shouldn't be allowed to practice.

thank you again so much for your help