View Full Version : Tub/Shower Overflow "Extra" Pipe

08-19-2008, 12:50 PM
Trying to help a friend who has experienced a serious flooding of the condo beneath hers. The problem is the result of something I have never before encountered (I am not a professional, just a victim of many years of rental property ownership and maintenance). The tub overflow is PVC and would appear perfectly normal except for one thing: near the bottom of the vertical overflow itself, there is a 1 1/2 wye, oriented vertically. Entering that wye, and simply going in at an odd angle, is a 1/2 PVC.

Here let me explain that this information was obtained while I was lying face down in the air-return under a closet HVAC system adjoining the bath, with my arms stretched out before me. I had punched through the sheetrock and was just able to reach the drain assembly.

I could reach my fingers into the wye and feel that the 1/2 simply ended about 2 inches into the open end of the wye. I could also feel that the interior sides of the wye seemed to be coated with a something that felt like a very smooth hard wax or epoxy-like coating, but whatever had been there was gone and it was all definitely now open to the atmosphere.:eek:

Sure enough, filling the tub enough that the water level reached higher than the top of the wye, then pulling the drain plug, immediately shot a spout of water out the top of the wye.

All I could do was extend a small hand mirror and by shining a flashlight I could see that the 1/2 PVC went up and made a 90-degree turn toward the centerline of the shower , then made another 90 and appeared to be threaded to a connector of some sort, which might have been at about the height of the faucet assembly. Unfortunately, it was very difficult to see or judge exact distances. I also had to leave before being able to investigate any further, so was only able to plug the open-end of the wye with a handful of putty for now.

I live about 150 miles from that location and thought I would try to find out what might be going on with that extra connection. It would appear that the function itself is an intended one, but that the installer perhaps did not have the proper bushings or adapters and did some sort of make-do. The original work was done in the 1980's and it may have gone bad many years ago. It would still be unnoticed had not my friend had a friend of hers staying there who happened to have filled the tub fully for a soak, and then pulled the plug which did quite a bit of damage to the condo below.

The only thing I can even imagine is that it is some sort of leak/leakage protection built into the faucet assembly (single handled, the diverter is in the fill spout). I did have time to pull the spout and see that it was a perfectly normal thread-on type.

It is a steel tub and a tile surround.

Anyone seen this "extra" pipe before?



08-19-2008, 07:21 PM
Sounds like a condensate drain from the air conditioning....not connected in a proper manner.

08-20-2008, 03:59 AM

That has to be it! In crawling in and out of that air return, sometimes face up sometimes down and trying to wedge the hand mirror in there while pointing the flashlight with my mouth, I must have gotten even more disoriented than my normal state. I'll bet that pipe headed toward the HVAC and not back towards the shower. Damn, you're good.

Now I only have to figure out a one-handed fix.

Thanks for the insight.


08-20-2008, 07:57 AM
If you can reach the connection, find a plumbing supply that has a 1 1/2" x 3/4" Fernco coupling made just for that purpose.

08-20-2008, 06:07 PM

Yeah, that might be something that I could do one-handed, at least if I can cut the condensate pipe. I haven't been able to find any Fernco couplings that would quite work for that large of a difference in the two sides. I probably have to go over the 1 1/2 socket since I am afraid that I could never clean the socket well enough to get a bond to a new section of 1 1/2 PVC. Not sure what was originally used to "seal" that air gap.

The Fernco catalog does show a pipe sleeve adapter that might do the job. can't find them anywhere else. I'll have to see if they go retail.

I guess I'll just load up on about every coupling I can grab and see how it goes. Either try and build-up from the condensate line or down from the wye. I need to keep it flexible or it is bound to get snapped off whenever the HVAC gets replaced. If I make it flexible then it will only probably get snapped off.

EDITED: Air Gap Issue.

After chasing this a bit more, I see that connections of the condensate to the DWV (where code at all) require an air gap. This is in fact a small condo and I really don't want to risk pulling fumes back into the HVAC.

While it seems to me that the tub drain(if open) and/or the overflow port itself would easily satisfy the air-gap functional requirement even if I used the Fernco, the only only way that I can see for me to specifically add an air gap would be to extend a 1 1/2 PVC upward from the now-open wye socket to a height that was above the tub itself and then just inserting the condensate line into that (as it is done now, except at a level that is only at about 4 inches of water in the tub). I suppose it is possible that the line that enters the wye is actually the catch-pan drain, which I suppose would satisfy the air-gap, but I assume that it is in fact the main condensate drain. (If I wasn't 150 miles away I could make sure of that now.) In my case, I would be able to get to that area to run the 1 1/2 only by removing the air handler from the adjoining closet.

So... although I think the Fernco will work just fine using the overflow port for any functional need of an air gap, I have been known to be wrong- well known in fact. For the pros, maybe you can help: Where this condensate-to-tub is (or was) code, does anyone know of the standard connections that satisfy the air gap requirement?


08-21-2008, 10:10 AM
Your tub's overflow pipe is the air gap, just a specialized one.

08-21-2008, 11:22 AM

That sounds good to me!

Thanks again to all you guys, Terry included. This is the first Internet forum I have encountered with responses based on something other than ego.