Grey tank issues

[CBUTLER9697]

So my husband and I bought our 5th wheel used, in 2021. It is a 2001 cedar creek. We've never really had any issues up until now. A few days ago we noticed the water backing up into the shower and bathroom sink. We figured the tank was full, so I opened the valve and let it drain. Nothing happened. The water stayed. After a few hours it had gone down, but the issue has persisted. I've tried removing the u pipe directly under the shower incase it was a clog, we've used a plastic drain snake, vinegar and baking soda and as a last resort drano. Nothing works. I even went onto the roof and checked the vents and there was a wasp nest over the top of the vent, but I removed that. The bathroom sink now drains fine, but the shower is still backed up. I am at a loss as to what to do. Any advice would be greatly appreciated.

[lazyjj]

Stated above, you say your rig is a 2001. There is a possibility if the model year is correct that your tank valves may not be opening completely when you are dumping your grey tank and could use servicing/replacement. Over time they can become sticky. Just a thought I had after reading your post.

[MillMitch]

I don’t know about 2001 models, but newer models have a backflow valve in drain line to keep water from backing up into shower. That might need replacing if there is one.

[Reverse_snowbird]

First, if you get someone else to help you, tell them that you used Draino. That stuff is caustic. Wear gloves and eye protection if you do further repairs on that line.

Water backing up into the sink and shower are a sign that the grey water tank is full, but now that the bathroom sink is flowing that's a good sign. Did a lot of water come out of that tank when you cleared the wasp nest?
At this point, it sounds like you've got something plugging the shower pipe. Did you try running a snake through it again?

Welcome to the forum.

[Chuck_S]

Shower drain has 20 years of hair and grease in it. Plastic drain plumbing has been standard in houses for so many years the bottles don't even bother listing what plumbing they're safe for. GreenGobbler cleared one of my bathtubs of lots of dog fur and I know all the plumbing in this house is PVC plastic.

-- Chuck

[MR.M]

Originally Posted by MillMitch

I don’t know about 2001 models, but newer models have a backflow valve in drain line to keep water from backing up into shower. That might need replacing if there is one.

It's not a bac flow valve it's a hepa drain or something like that used in areas p-traps don't normally fit . but now they seem to be using them more . it's for sewer gas escaping not a back flow just an fyi

[bubbles]

Originally Posted by MR.M

It's not a bac flow valve it's a hepa drain or something like that used in areas p-traps don't normally fit . but now they seem to be using them more . it's for sewer gas escaping not a back flow just an fyi

It is also supposed to prevent backflow as it seals after water discharge.

[MR.M]

Originally Posted by bubbles

It is also supposed to prevent backflow as it seals after water discharge.

It seals to prevent sewer gas , same as a p-trap and installed where there is no room for a p-trap . not designed as a back flow for water .

[Thurman]

OP stated "I opened the valve and let it drain". I'm wondering IF this unit has the cables between the valve handle and the actual valve. I had a pull trailer at one time the when I pulled or pushed the valve handles it seemed to be working but nothing drained. I found that on both tanks the cables had come loose from the actual valve. There must have been three (3) feet between the valve handle and the actual valve. Recommendation to "CBUTLER9697": Look to see if the valve handle you are pulling is directly attached to the valve or IF there is a cable in between the valve handle and the valve and if so is it working correctly. If it's directly connected then I also agree that there may be some type of blockage between the drain hole in the shower and the tank.

[JEB2023]

Brand new to rv living, we have a 2020 Palamino Columbus that we just purchased. Making the transition to living full time in our RV. We are at a park with hookups and we leave our grey tank open all the time until we need to dump the black tank, then we close the grey for a couple of days to ensure we have water to flush the line. We have only been in the RV for a few weeks and the bathroom sinks and shower have started to backup. I used baking soda and vinegar last night on all three drains and the shower is better but the sinks will still back up after less than a minute into the sinks. They do drain after I turn the water off at the faucet. I have was on the roof the roof the other day and didn’t notice that I had any nests. Please help with any ideas.