Infuriating Shower Problem

I posted a similar msg about a month ago, but got no replies..thought I would try again.
The following problem has been going on since a Delta 2 handle, shower only, faucet (and new shower) were installed 5 years ago. It's driving me nuts, and nobody seems to have any idea what I should do. I would be greatly appreciative if someone could give me a suggestion.
A few months after this was installed about 5 years ago, the water pressure gradually reduced to a very poor level. (about 1.4 gal/minute) I tried the usual things: of course took the shower head off; also removed the valves and purged into the shower from the source -- tons of pressure, no help.
Then, assuming that the clog was between the faucets and the head, I removed the valves, attached a garden hose to the head pipe, and flushed out from the head out into the shower thru the valves. THIS WORKED (2.5 gallons/minute), BUT ONLY TEMPORARILY. Within a week or two the pressure began to decrease again. I have done the above 3 times now. Each time it fixes the problem for a while, and then reverts back to poor pressure.
My only conclusion is that there is some stuff lodged north of the valves and with time, it moves to a place where it can constrict the flow. I have tried snaking some wire from the head down..but could only reach about 3/4 down towards the faucets. OR something is wrong with the valves, but I can't imagine what. The pipes from the source are copper..the pipe going up to the head is older (galvanized?)
Do you have any thoughts? I'm about ready to bust up the wall and replace everything from the faucets on up (I really don't want to do that)
Thanks very much
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Consider adding a whole house filter ???
--

SVL



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
MNP wrote:

You've done everything I would have done. The galv riser is suspicious in itself; it may be time to bite the bullet...
Jim
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
onclusion is that there is some stuff lodged north of the valves

I'd suspect the galv section, but first I would try really flushing the pipe with very hot water and various chemicals, maybe even radiator cleaner.
--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Any chance some pipe comppound's gotten in and built up somewhere? Pretty nasty stuff to get out with heat, pressure, even chemicals.
Pop

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
thanks everybody for your replies... yes it looks like it might be time to bust up some tile and see what's what

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
MNP wrote:

Any chance the shower wall backs up to another room so you could break open drywall rather than the tile? Jim
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The galvanized is probably the problem. It gets clogged up inside from mineral deposits. Don't try to clean it out, though. Galvanized pipe can develop pinholes and if you get rid of the mineral deposits, it can start to leak.
I had a whole house full of the stuff, so I've had experience in this area.
I would bite the bullet and replace it. If you don't, you will have endless problems.
Steve
some random words that came up with:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.