Just replaced tub with shower. The tub always drained fine but the new shower won't start draining until you plunge it. Then it drains fine as long as water is running down the drain. Ideas?

It sounds like you disturbed some gunk built up in the pipe walls when you made the conversion. The solution would be to remove the strainer and snake the shower. M Run out about 12 feet. After. Flush with a large pan of boiling water. Good luck, Tom

It sounds like you disturbed some gunk built up in the pipe walls when you made the conversion. The solution would be to remove the strainer and snake the shower. m Run out about 12 feet. After. flush with a large pan of boiling water. Good luck, Tom


Snaked it already but did not follow with boiling water. Why would it flow fine with one plunge each time and stop up right after the water stops flowing? A friend did the work and I don't think he removed the original trap under the tub and added one when he relocated the drain to the center. Could this cause my symptoms?

Sounds like you might have a venting or restriction issue. When you plunge, it opens up a way for the air to go down. Make sure your friend didn't install another trap in addition to the one from the tub. This draining problem is not uncommon in new undermount sinks that don't have an overflow drain. You need a special sink drain to allow air in. Tubs have an overflow, showers do not. There is very little head pressure in a shower but lots more in a tub.

Sounds like you might have a venting or restriction issue. When you plunge, it opens up a way for the air to go down. Make sure your friend didn't install another trap in addition to the one from the tub. This draining problem is not uncommon in new undermount sinks that don't have an overflow drain. You need a special sink drain to allow air in. Tubs have an overflow, showers do not. There is very little head pressure in a shower but lots more in a tub.

So does it need a vent stack or would removing the other trap do it?

If properly installed to begin with you should have a stack within the distance requirements. Are there 2 traps?

If properly installed to begin with you should have a stack within the distance requirements. Are there 2 traps?

I believe so. It's within 4 feet of the main stack.