I have a new house (lived in three years) and have a shower plus a combo tub/shower valvein another bath. These are Moen valves (probably antiscald).I see both have small in line stop ball valves. The problem, there isn't a lick of pressure comes out either valve for taking a shower. I've tried everything including flushing with core out and noted good pressure, I have replaced the moen cartridge after calling MOEN and complaining about the poor pressure. They have such poor pressure wife and daughter can't rinse longer hair out after shampooing.

Are these Moen valves noted by anybody else as water stingy as I have found? What do I have to do. We virtually have marked the showers as unusable.

bullshooter5

Do you have good water flow at the tub spout but not at the shower head? If so remove shower head and look for obstruction. You may want to remove water saving disc in shower head.

Does you Moen have an integral valve built into it or are there external stops on each side. I use Moen all the time and there is no issue with them. I think your stops are plugging up but I can go any further until I hear back from you. Harold asked a question and we await the answer,remove any restrictor plate just to see if that is the isuue, or heck remove the whole shower head if you want.

Good morning ballengerb1 and Harold,

Thanks much for your answers.

Harold, I don't believe the shower heads are plugging as I can completely remove it and the water flow is still insufficient. Thanks for the response.

ballengerb1. Stops plugging? Now, We might have something here. I did not mention, I have very hard water... I mean stone age hard... even though I have twin tank Culligan softner. Yes, these Moen valves have those little bitty stops built in to the valve head. I have turned them to stop the valve to remove the center stem valve and they have effectively stopped water. I have suspected they are so little and are obviously a ball valve that with a littlle hard water deposit could slow water passage when they are open. They are of course wide open but flow could be restricted. Is there a way to clean them up or do they have to be replaced?

Good calls to both.

Bs5

I think you have just answered you own question. Turn off water and remove stop valves and clean. If you can find plugs to fit size and thread of stop valve opening (which I doubt) you could plug them. But then you valve ports would probably build accumulate mineral deposits.

Wait a minute, you did not explicitly say weather or not you have good flow at the tub spout, I assume not. Also do you have the same volume hot and cold?

Hi HK,

The shower is shower only but right next to it I have a jacuzzi and there is no doubt about it having very good pressure. I agree with you guys, the stops have to be suspected... they are so darn little. It's going to need removal and replacing but I will have a time with this. I hate leaks worse than low pressure but as it currently is, the shower remaiins a useless fixtture. I have to think of a way to reward ballengerb1 as I was going to score you both winners but after I rewarded you it said one was all I could reward. Sorry ballenger unless I start another thread and have him answer and then score him but perhaps that is not allowed. Let me know if I can get it accomplished somehow somehow. Thanks for two great responses.

Bs5

Ok, I have used a new shower head as well as ran it with the drop only and no head findinig no noticeable improvement Then I disassembled the Moen valve removing the stem valve cartridge. I remember the instructions given last time I called Moen to complain about their stingy on water flow rates they were good enough to send me a replacement but the tech warned me to make sure the valve rattled when shook. It didn't so that means you have to remove the little piston after removing a white plastic plug in end. Relube the thing with sticky silicone gel ( that's what she told me) which after it failed to rattle this piston when shook so I then removed the cartridge again, cleaned and got the piston freed up instead of stuck to sides of valve tube with silicone.

So all that was done and then I tried revolving the stops with a screw driver and found they felt a bit dirty. So, I managed to get them working freeely and left them open. Now while the little ball valves are open and stem cartridge removed I turned water back on and flushed water through the valve thinking maybe I had removed some hard water deposit by revolving ball valve and a blast of water would blow it clean. After putting it back together I thought there, take that. Now, it's time to see if I did any good. Turned pump back on plenty of pressure every where except the shower. The only thing I did not due is remove that little snap ring holding that tiny ball stop valve and clean. Quite truthfully, I am almost afraid to because I'm afraid of either not getting it to go back together or having a leak. I already managed to get water in wall cavity from flushing valve with out stem valvle. Do I dare remove those two internal snap rings and proceed to remove and clean ball valves? That has got to be the problem. The tub spiggot at other bathroom is for bath and shower. There is unacceptable levels from both tub and shower valves when used. For a shower it is even more imperative you get better pressure.

I'm all ears.

Bs5

If I am correctly following you adventure, with the water turned off you removed the cartridge, then turned the stop valves to the on position and felt "gritty" feel. Or at least not the smooth action you would expect from a machined two machined surfaces. You then turned the water back on hoping that you had dislodged some of the mineral build up and could flush it out. You don't know what kind of water flow you had because you were at the main shut off valve. You just made a mess inside of the wall (sorry about that, but don't worry it will dry).
If all of this is correct, I think that you are correct that you must remove the stop valve stems and clean. You will probably need the proper "C" clamp or snap ring tool. If you get them out you should be able to get them back in. If you get them back in far enough to get the snap or C clamps back in the grooves they fit in they won't leak.

The only other alternative is to replace the entire valve, so if you can't get the stop valves back in properly you haven't lost anything but you time. Buy another valve, without stops and have it on hand. If you don't use it return it. This doesn't sound like a fault of the Moen brand of valve, more the mineral deposits in your water. Any other brand will have the same problem eventually.

Yep, its time to disassemble and clean the integral stops. They aren't that complicated and it's a good idea to stuff a towel in and under the valve just to catch fallen parts. Most of the Moen mixing valves I install do not have the integral stops and that's fine with me. They are a convenience when working alone but just one more place for crud to catch.

a good idea to stuff a towel in and under the valve just to catch fallen parts

That's a darn good idea.