Tracing down a water pressure problem

I have a problem with the upstairs bathtub/shower. It takes 45 minutes to fill the tub with water, and the shower pressure is weak.

The type of valve is this style.
http://i.stack.imgur.com/CTAHDl.jpg

The rest of the house has lots of water pressure, and in that bathroom, the toilet and sink have lots of pressure. Its a specific problem to that bathtub.

I can't be certain but the problem seemed to arise last winter when the city turned the water for for a few hours to repair a main.

Debrise did enter the house once they turned it back on, had to clean all the aerators in the sinks. Was some pretty big chunks.

Is it possible that debrise can clog this valve up to that extent where there is no pressure to fill the tub or shower? How easy of a repair is this and is it something I should even be attempting as an amateur handyman? If I remove that silver cover is there enough access to even do any repairs?

Thanks for any input on this!

it is obvious as to what the problem is

if your handy type person, take valve apart and clean it

if you are uncomfortable doing so, call a plumber

I replaced the water cartridge with a brand new one, water still trickles out of the tub faucet. Anything else cause the low flow?

take it apart. COMPLETLY .. blow the line out

have your helper turn the meter on.

you might want to open a window, things could get real interesting of someone is not paying attention.

let it blow. hold a towel over the valve to direct water into the tub, not the rest of the house

have your helper turn it off..need to use a helper than moves quickly, slow at this point is not advised

when i do this, all i YELL is turn it on

and YELL turn it off.

have a wire handy, if you are not getting water, send the wire up in the pipe and juge it around

hopefully you will get the crud out

remove shower head and clean it

Casper said:

I replaced the water cartridge with a brand new one, water still trickles out of the tub faucet. Anything else cause the low flow?

Click to expand...

You replaced the cartridge, But did you replace the 2 small neoprene cups and springs in the valve behind the cartridge.
Like FRODO said, you need to flush it.

This is what the cartridge looks like.

http://ecx.images-amazon.com/images/I/31QGEN619PL.jpg

I'll take it apart again on the weekend when the wife's home, try blowing it out with the cartridge out.

Thanks.

I finally had a chance to get at this again. Took it all apart, and tried to blow it out on my own. from the time it took me to get from downstairs to upstairs and back downstairs, the tub was 1/2 full of water (and so was 90% of the bathroom), so there definitely is no problem with pressure upstairs. enough pressure it was spraying off the back wall of the bathtub, so like 6 feet away. (wife is going to love the mess I made when she gets home)

I put the cartridge back in, still no pressure out the faucet, just trickles. There is only one way the cartridge can go in because of the locking pin, so i know I'm not putting it in crooked.

I took the spout off, tried running without it, no difference.

I wish I understood better how that valve worked so I would know where to be checking for a blockage. It looks like there is a hole on the bottom leading to the tub, and another in the back that leads to the shower. So when the blocker on the faucet is applied, it should divert the water back through the cartridge to the pipe leading to the showerhead.

It seems so simple, just don't understand why its not working.

forgot one more thing, here is a photo of the inside of the valve. This is also with the tub faucet removed. Notice the water is still sitting on the bottom instead of draining into the tub.

That be a good indication their is a blockage in the actual valve assembly? I tried shoving pipe cleaners down that small hole on the bottom. I wonder about draining the pipe to the tub and blocking it off, then filling it with CLR for a few hours.

I have sprayed clr in the pipes for the shower and spout and it has cleared the line ..

Just a follow up. I removed the shower head and tub spout. Plugged off the copper pipe to the tub. Filled the lines from the shower pipe with vinegar and left it for 3 hours. Unplugged the copper pipe, dark blue green vinegar came pouring out. Full pressure restored to both shower and tub spout.