Shower clog or something else?

[BeeDub]

I have an interesting problem that I have never seen before. During our last outing, I noticed there was standing water in the shower drain after the first shower was taken in the rig. I found it hard to believe that the grey water tank needed dumping already. So I opened all the valves to the tanks to drain all the water/wastewater. Still had standing water in the drain. I poured a bucket of hot water down, thinking maybe there was a clog and it would rinse it out. Interestingly enough, the water drained fast, but yet there was still standing water in the drain. We took another shower, and there was never any problem with a slow drain (the water drained fine and never backed up), but always standing water inside the drain.

Brought the rig home and drained out everything - grey, black, fresh, low-point drains, etc. Still standing water in drain. Used the vinegar & baking soda solution but it didn't help. Tried flushing it with the garden hose - nothing. Tried using that plastic hair drain tool - nothing. I am stumped as to why I can get all the water flushed out of the shower pipes.

After looking at the piping, it looks like there is no p-trap for the shower drain. Anyone have any suggestions as to what my problem is and how I can fix it?

[dougrainer]

Dutch_12078 wrote:

mchero wrote:
I'd get one of those devices you stick down the drain and rotate to get hair out. I was AMAZED at the amount I pulled from our shower and sink drains!

Reread the first post, he already tried that. I don't recommend those clog sticks for Hepvo's though, since the "teeth" on the stick can damage or invert the "duck" lips that seal the odors out.

BINGO. Any Snake that goes THRU the Duck Lips will invert the lips when pulling it back out. Now, just to stick a few inches into the drain is OK. The Hepvo valve is at least 6 inches from the drain. They also recommend that you put a tablespoon of vegetable oil down any drain that has a Hepvo valve to help keep the Duck lips from sticking once a month. Doug

[Dutch_12078]

mchero wrote:
I'd get one of those devices you stick down the drain and rotate to get hair out. I was AMAZED at the amount I pulled from our shower and sink drains!

Reread the first post, he already tried that. I don't recommend those clog sticks for Hepvo's though, since the "teeth" on the stick can damage or invert the "duck" lips that seal the odors out.

[mchero]

I'd get one of those devices you stick down the drain and rotate to get hair out. I was AMAZED at the amount I pulled from our shower and sink drains!

[Dave_H_M]

I suppose you make sure some antifreeze goes in the drain trap for the winter?

[BeeDub]

dougrainer wrote:
If the water is NOT in the shower pan but you can see it below the round strainer, that is NORMAL. For either a Hepvo or P trap system. That is your Water barrier to keep gas/odors from coming back up. Doug

So that is exactly the situation I have. But I guess my concern is that normally when I open all the valves to drain all the tanks, especially in fall when I winterize, I don't ever recall seeing this water down in the drain. Everything is functioning properly the way it should, so for now I won't worry about it.

[dougrainer]

If the water is NOT in the shower pan but you can see it below the round strainer, that is NORMAL. For either a Hepvo or P trap system. That is your Water barrier to keep gas/odors from coming back up. Doug

[remdog_1]

Check the grey tank vent for blockage. If vent clogged it won't drain

[dougrainer]

Fisherman wrote:
Use a toilet plunger and blast it out.

NEVER DO THIS WITH A HEPVO VALVE!!!!!!!!!!!!!!!!!!!!!!! THE PLUNGER SUCTION ACTION WILL PULL THE HEPVO VALVE "DUCK" LIPS BACKWARD TOWARDS THE DRAIN, RENDERING IT ALMOST USELESS. HOW DO I KNOW THIS??????? I DID THIS A FEW YEARS AGO AND MADE THE PROBLEM WORSE. I THEN PULLED THE HEPVO VALVE AND FOUND THE LIPS PULLED BACKWARD. LUCKILY YOU CAN JUST PUSH THEM THE OTHER WAY ONCE IT IS PULLED. Doug

[pigman1]

Fisherman wrote:
Use a toilet plunger and blast it out.

That'll work, but go easy at first. I usually have the problem on the first shower after a long dry spell. When still in the shower I stomp hard on the drain a few times with the ball of my foot. Works every time for us. After the first time it usually works fine for the rest of the trip.

[Fisherman]

Use a toilet plunger and blast it out.

[Roger10378]

So is the water standing in the shower pan or only down in the drain. There is supposed to be some water in the drain. The water is what keeps the tank smell from coming into the trailer.

[Lynnmor]

Dutch_12078 wrote:
Some RV's use a "Hepvo" or similar inline seal instead a traditional 'P' trap. The rubber "flutter valve" seal opens when there's sufficient flow through it, and it's normal to see some retained water in the drain. As the valve ages, it can get stiffer and retain more water than when new.

Hepvo Waterless Valve

Likely the problem. If you have room to replace it with a P trap, that would be good.

[larry_cad]

Hair buildup in the drain.

[Dutch_12078]

Some RV's use a "Hepvo" or similar inline seal instead a traditional 'P' trap. The rubber "flutter valve" seal opens when there's sufficient flow through it, and it's normal to see some retained water in the drain. As the valve ages, it can get stiffer and retain more water than when new.

Hepvo Waterless Valve