Plumbing – Is this singe-handle shower valve servicable? If so how would I find the source of a steady drip when the valve is shut off

plumbingshowervalve

My mother's house has a shower that has a perpetual drip; the valve is likely original to the house (probably ~1970) and I expected it to be a pressure-balancing valve with a cartridge and replacable o-rings and gaskets that were likely deteriorating.

The valve operates by pulling out to allow the water to flow and pushing in to shut off the water. Twisting it controls the temperature. I've removed the cover and didn't find what I expected–so I took these photos:

  • The cover plate has been removed, the cover does not hold the handle in place (the handle could be removed with the cover on).

Cover Plate Removed

  • The valve with the handle assembly removed

Valve

  • Another view of the valve

Valve

  • The handle assembly

Handle assembly

I expected the black plastic to be a removable cartridge, but it seems to be firmly in place (I've just tried twisting and pulling by hand–not much force, but it doesn't budge or wiggle). The handle screws pass through the black plastic and into the body behind it.

So, the main question: Does this unit appear to be serviceable–if so how can I get deeper to identify the cause of the drip–how would I pull the black plastic without damaging it? Or is it just time to get into the wall from behind and replace the whole valve?

…and yes, it'll get caulked during reassambly

Best Answer

Glad you found your answer.

I've also had slow leaks (drips) like you experienced due to (1) solder spatter inside the valve that prevented a good seal on the rubber, and (2) plumber soldering the pipe with the cartridge in place which hardened the rubber so it didn't seal well.