I have one of those fiberglass/plastic shower stalls on my 2nd floor and recently the brass “no caulk” drain started to leak on the ceiling below. The drain is supposed to be “no caulk” meaning it relies on the compression of a gasket to make the watertight seal instead of caulking however from what I have read people still use silicone or putty or thread sealants to make it watertight.
There are two threaded parts on the drain body/ flange. One is on the inside and one is on the outside. The inner threaded portion accepts a rubber gasket that goes around the plastic/pvc pipe riser and tightens with a nut from the top. Then there is another locking nut with a rubber and a paper washer that tightens from the bottom and tightens to the bottom of the shower floor. So there are two potential places the drain could leak, around the pipe and under the drain flange.
I cut an an access hole in the ceiling below and put in new washers/gaskets on the top and bottom. I used silcone on the underside of the drain flange which was recommended by someone at the local plumbing place and pressed it down hard, then tightened the bottom locking nut as hard as I could with a hammer and screwdriver. On the inner threaded portion I put in the rubber gasket around the pvc pipe and then coated the nut with thread sealant and tightened it down very hard with a hammer and screwdriver.
So far I have run the shower for 30 minutes with zero leaks.
However I am concerned about the threaded nut underneath coming loose over time or water running through the threads. Should I simply try to tighten it more or take it off and put thread sealant on it and then retighten it again.
thanks
In situations like this I tend to go overkill. I’ll first wrap the threaded portion in teflon tape, then apply something like RectorSeal’s teflon putty over the tape. If you’re mating metal fittings to PVC you always have to be really careful not to over torque the metal fittings to avoid cracking the PVC. Sounds like you’re probably OK though.
Plumber’s putty is also great for a non-permanent water seal on threaded joints.
My experience dictates that the more you try to reinforce/check things they tend to break. If you must check though, as in letting it run it for 30 minutes with no leaks, try it with a little bit of pressure to be sure. Fill up the shower basin (im assuming here) and block the drain… let it fill a little plunge some water down the drain and then let it drain, if nothing comes out, you’re good to go. I did this when I put my shower in to check, no leaks and its been going strong!
If you have already used thread sealant I don’t see how taking it apart and redoing it is going to change anything. I don’t think the threads are likely to be the issue for a drain as the pressure is not high. That being said, anomalous1 is certainly correct when saying that pressure is key when testing a drain. I find that just running water down a drain is not sufficient to test the drain assembly for leaks, filling the basin first will reveal leaks that simply running the water won’t.
From my experience the most likely cause of the leak was the flange so siliconing that will probably fix it. It can be hard to compress the gasket enough to get a good seal, so putty or silicone is a better solution. A note about putty, I recently remarked when I saw one of our plumbers using silicone instead of putty when installing a sink basket. He said despite manufacturers claims to the contrary he has seen too many cases of dried out and cracked putty to trust it any more.