I own a duplex townhouse. The bathroom is upstairs. It has had low pressure for awhile (18mo or so). I hired a professional to replace the pipes(2 wks ago) and hoped that removing the old iron pipes would improve the pressure. The pros replaced only about 4' of the supply line, then the pipes dropped down a wall. When they were done the bathroom sink, which had been working with good pressure, had low pressure.

I decided I could not go on with the old pipes and this problem. I cut into a chimney wall and was able to put the hot and cold lines directly from the main line in and the hot water tank in the basement up to the new PEX the Pros put in two weeks ago. I replaced everything in the building with PEX. I had 3/8" soft tubing supplying the hot water tank and leading away from it. It was wrapped in insulation. I had no idea such small lines were used. I put 3/4" for the new supply line in and for the hot water out of the tank. Then at each of the fixtures I reduced the line to 1/2". I also put in ball valves so I can turn off water to any fixture or area.

About one year ago I updated this bathroom with a new tile around the tub. At the time the faucet was a little weak, but not terrible. After the remodel it seems the pressure really tanked. So that is when I called a plumber to work on the cartridge and check for debris in the system. He said he changed the cartridge. (1 year ago) So I went ahead with the new tile and thought after the work the fixture would work well. (I was wrong.)

I have a Price Pfister single pull on/ push off tub/shower set up. I want to ask now that ALL the pipes are new what could be causing this issue if not the cartridge? I also wanted to know about replacing the cartridge, as the faucet assembly is older. I wish I would have replaced the whole thing, but I didn't So I want to get the correct cartridge. My tub kit is a chrome oval octagon shaped with a single round handle in the center. I think this unit is from the 90's.(In reading the archives I read someone saying replacements were available for many of the older systems "unless it is octagon". Which mine is.) Help on improving my tub's water pressure is appreciated.

Now to my questions:Which cartridge do I need? Can improper installation cause the problem? (So if the plumber I hired put it in wrong could that cause the issue?)How do I know IF I need a new cartridge or something else? Must I put in a temp.controller? Could that be the issue?

The octagon only makes it difficult to replace that trim piece, all the rest is generic with Pfister. You have an Avante valve and ALL of them use the same cartridge/stem, but there is nothing in the piece to cause a pressure problem. Your shower head by be obstructed, especially if the pressure/volume do not change when you go from cold to warm to hot.

It comes out of the spigot low too, so I didn't think it was just the shower head, which I did clean and soak in vinegar. (I bought it for low pressure showers a year ago.) When I take the valve apart to replace can I fish a line into the pipes from there to see if something is blocking in the pipe next to the valve? Perhaps it is not the pipes per se, nor the cartridge, but with all the work that's been done to open the waterlines perhaps something caught right at the junction for the tub/shower. Is it possible to clean that? Thank you so much for the advice on what type of shower I have. I will get the replacement for the model you said.



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depending on the configuration of your pipes, you may be able to blow compressed air backwards thru the valve. ???

So in a nutshell, they changed 4' of pipe and now you have reduced volume at both the sink and the shower? Try removing the aerator on the sink first and turn it on. Is the pressure good and the aerator full of rust chunks, or is it still slow? Did this 'professional' not check the water flow after he completed his work?

Well,I have replaced all the lines now and still have not so good shower pressure, so Price-Pfister is sending me a new cartridge to replace the one I just had put in. I think it will do the trick... at least I hope so. There's nothing left.