Our shower has a 6-8 year old Pegasus single-control shower valve installed. After a couple years, you could turn the valve all the way to the "hot" end and not get much hot water... and the handle felt "loose". I called customer service and they sent me a new valve cartridge, which I installed. Problem resolved...

Although it did not happen right away, after a few months, the shower started to make a loud staccato noise, somewhat like an impact driver, but not when we close the valve... it happens when we open the valve. I've received more than a dozen replacement cartridges for the valve from customer service, but changing the cartridge nolonger helps the problem.

To clarify, this valve is either on or off (no flow control), but you turn it counter-clockwise from the 6 o'clock position (off), through cold at 5 o'clock and 4 o'clock... all the way to about 1 o'clock, which is hot.

To dive into the problem deeper, I'll try to tell you what I know it does and doesn't do:
1) If I just turn on the water, as soon as I get the valve to about 3 o'clock, it starts making the sound like I'm using an impact driver. Turning the water off brings quiet.
2) If I pull up on the diverter valve on the spout, turn on the valve to the 5 o'clock position, wait for the pipes to load and water to come out of the shower head, I can move the handle all the way to hot without the noise.
3) I'm told that if someone has started the shower in an adjacent bathroom, the noise does not happen.
4) I have not found any consistency in how long the hammering noise lasts... I haven't been able to tolerate it long enough to see how long it lasts.

From this, I've concluded that:
a) it's the hot side that is causing the problem, because it starts when I'm at about 3 o'clock, which should be when the hot side opens; and
b) it's a pressure issue of some sort, since if a nearby valve is open or if the pressure has stabilized, the noise does not occur.

Thinking that it's related to water hammer, I've tried to drain the system and recharge the hammer arresters, starting with the highest and furthest faucet from the water meter... with no change in the problem.

As I mentioned earlier, I've changed the cartridge several times. Customer service has sent me a replacement valve body to install, but if I replace the valve body, I'll install another brand.

Yesterday, I found a reference to the stop valves on the valve body. So I took them apart to see what condition they are in. At first, I would say they were both stuck open, but after a little manipulation I was able to make them move smoothly and I reinstalled them.

Still, I have this impact driver noise and I'm out of ideas... Does anyone have any suggestions for me?

Thanks.

It sounds like an issue with the balancing spool. I'm not sure if it's part of the cartridge or a separate piece in the Pegasus faucets. They are a low end faucet and in all honesty I'd probably just replace it with a Delta.

I agree that it is "low end". We bought it because it was "pretty"...

I would like to replace it with Delta, but I'm not sure of my skills enough to tackle it, considering where it is. I think I'm looking at somewhere between $600-$1,000 for a licensed plumber, plus materials. I have already had two look at it and they both refused the job. The shower was recently tiled ($1,000) and it backs up to a vanity with a granite top and a tiny cabinet below the vanity top. I'm not sure I can get it apart without destroying the granite or the tile.

Thanks.



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