Single outlet pressure problems

[Kurgen]

Hey guys,

One of my upstairs showers is experiencing a low pressure situation. It is low at start and drops as the shower continues. I replaced all three valves to stop the leaks and replaced the showerhead, but it did noting to help the pressure. Pressure is good in all other baths. The house was repiped with flex hose a few years ago. The valve body and stand pipe to the showerhead are original.

Could this be a scale issue or some other blockage in the valve body? If so, will that cause the pressure drop I noted during use? My next step to solve this issue was to replace the valve body and stand pipe, but I thought I would check here first as it is my brother's house and he will be pissed if I suggest he spend the money and it does not good.

Thanks in advance.

 

[phishfood]

You say the house was repiped with flex hose, what do you mean by flex hose?

 

[Kurgen]

Thanks for the reply. It is blue and red plastic pipe feeding from a manifold in an upstairs closet. All the old galvanized pipe is gone or bypassed. I don't know the exact name of the pipe. It is flexible and feeds directly into the existing fixtures. The ones going to the fixture in question are 1/2" size, same as most coming out of the manifold.

 

[phishfood]

Thanks for the clarification. Sounds like the house has been repiped with crosslinked polyethylene, also known as PEX. 1/2" is sufficient in size.

It does sound like the valve may be the culprit.

 

[Kurgen]

Thanks. I was thinking that as well, I just did not see much scaling or debris in the valve body when I pulled and replaced the valves. Thus I was skeptical about the issue. I will go that route and see if it fixes the problem.

Thanks again for the help.

 

[ExtraMilePlumbing]

Also before that you want to pull out the stems and turn the water on to see if you're getting enough pressure there

 

[Kurgen]

Excellent addition. Thanks for the idea. I will do that.