Any idea what on earth this thing is for? (see pics)


After some hunting I have traced a huge leak to it's source. Luckily I have been able to open up the wall of the master bedroom to expose the back of the main and ensuite bathroom tub/shower plumbing. I can see both at the same time. The ensuite tub/shower plumbing (on the right in the pic) is totally normal.

The main shower is causing a huge leak to my master bedroom carpet and under my 2nd floor laundry room and down into the 2-pc-powder room below.
Turns out, there is a strange overflow contraption which has been sauldered into the line between the faucet and shower head. It is a 22 inch length of very skinny copper piping fully inserted into a 3/4 inch white translucent pvc tubing. The pvc tubing passes down into the floor and connects to the floor drain of the laundry room (9 feet away). When the shower is activated the water that is not flowing into the shower/tub, is flowing down the pvc tube and into the drain. What a waste.

I recently installed a low-flow shower head in the main shower and that's when the trouble started. The increased pressure to this overflow-like system is pouring with such force into the laundry room drain that it is flowing upwards and over the edge of the floor drain (though below the level of the laundry room floor tile) and dripping down the outside of the pipe to the elbow and then dripping down into the 2-pc powder room. Some water then also backs up to the top of the pvc tubing and runs down inside the wall and soaks the carpet.

Any idea what on earth this thing is for? It totally defeats the purpose of a low-flow shower head, as I am now sending most of my water directly down the drain. I am appalled.

Attached Images

  

What you have is called a "trap primer". And not a very good one at that. That's there to provide water for the floor drain trap.
Your solution would be to cap off and remove the PVC tube, If the floor drain's unused then pour a quart of cooking oil down the floor drain and forget it. Good luck, Tom

Thank-you so much Tom. I have also heard the term "drip line". Could I not also change the location of the primer? So that it maybe takes water from the supply for the laundry room? It is an unused drain until I have a major washing machine malfunction, then it will of course be very necessary. Would a quart of cooking oil not go rancid over time?

Denise

I guess my solution didn't register so I'll try again. You don't need that trap primer, (drip line) period. Cap it off and if you don't like cooking or motor oil then pour a quart of Anti-Freeze down the trap. Is there any misunderstanding about this solution? Good luck, bTom

I agree with Tom. Simply cap the primer at the shower riser and be done with it. If you don't want to put anything other than water down the floor drain, just make sure to dump a couple cups of water down it every few months or so to keep the trap primed. In my opinion trap primers are more of a hassle than they are worth. Only place I agree with using them is in commercial buildings that have a full time maintenance crew that check the primers regularly to make sure they are operating correctly. And even then, if they have a crew to check the primers, I would think it would be easier for them to just check the trap and add water as needed? Trap primers tend to fail one way or another. Either they plug up and don't work, or fail and run water constantly. Lose lose situation in my opinion.

Well...
I did clearly understand your solution, Tom. Since I am a grade 4 teacher and not a plumber, I did not read into your first post that I "don't need a primer period".

Thank-you 'mygirlsdad77' for your helpful input.

So now that you have a solution what are you going to do with it? Back to you, b Tom

Did it this morning. Cut out primer, installed a straight piece of copper pipe and removed pvc tubing. I will throw some water down the drain routinely - on the same day of the month that I test the smoke detectors.

Thanks for the help.