We had a great deal of trouble with what seems to have been a stripped screw, eventually we were able to pull out the mechanism with pliers. Here is what we pulled out. It is unlike anything expected per any how to articles or videos we watched first. In particular, there is no hex nut that needed unscrewing to pull out a thing behind it using the shower valve socket wrench we'd bought.
We are just not sure what this is, what vocabulary to use to find out what we need to buy to replace it. We go to Lowes and ask for a… what?
Meanwhile, related issue, even though we have shut down the water in the house, there is still a constant drip coming through where this was attached to the plumbing system. So we believe we cannot turn the water back on or it will simply gush freely. Any idea why the water seems to be slowed to a trickle rather than shut completely off? We've got that thing shut tight as seems humanly possible. Is there likely to be anything we can do about it?
Best Answer
@Kris said nearly, precisely what I had planned to say. I'll break my answer down into 2 parts, as that is how you asked your question.
A. What is it and how to get a replacement part? It does appear to be a shower valve cartridge. It will be helpful to have the following information on hand when you go to get help with the replacement part.
B. Why is there a slow trickle when the main is shut off? Over time sediment buildup is common place from each time the city supply lines are worked on. This can cause a poor seal or scratches the rubber seat and prevents a complete seal from ever occurring. This is common and it happens because we are not in the habit of operating these valves regularly like we do a water faucet, nor would I really suggest doing it. You'd probably experience the same behavior if you've ever turned off a toilet or faucet supply valve to replace a supply line; near impossible to stop them from exhibiting a slow drip. Here are some steps you can take to fix the issue.
When turning the water back on from meter to house, make sure the home supply valve is in off position and turn the water back on about 1/8 turn per ~10-15 seconds. This will prevent shocking the system with a bunch of water pressure that hits a wall and causes pipe and joint ruptures.
For the house supply valve, put the shower valve back together and leave the trim off so you can verify no leaks at the repair site. Turn on a nearby sink to prevent a water surge to the system that would cause pipe and joint rupture; same as previously mentioned. Also turn the water on slowly, same as before. Then turn the sink off and check for leaks at the repair site. If no leaks, turn on all the faucets in the house to purge air and debris. Once the system is completely burped at each faucet, turn each one off and put the trim back on the shower valve. Congratulations, you finished repairing your shower valve!