Gray Water Tank Suddenly Not Draining at All

[SMKovalchik]

Have looked through topics and haven’t found this problem. We have an ‘18 30’ Classic. Tonight, for the first time, the gray water won’t drain. We closed it yesterday to collect water to flush after draining the black tank. Normal procedure. When we opened the gray valve nothing came out, not one drop. Need suggestions. Of course it’s Friday night so no chance of help over the weekend.

[twobikes]

Check the side to side level of your dump site…we once pulled into an interstate rest area dump site and NOTHING from either tank. The spot was on a curve and was slanted Away from the drain by a lot.

[GCinSC2]

Are you somewhere exposed to freezing temps?

Handle pull effort normal?

[SMKovalchik]

We’re actually on our RV lot in FL and leveling isn’t an issue but thank you for your try.

[SMKovalchik]

No freezing temps. We’re in FL. Husband says the pull seemed to be what it always is. 45+ yrs of RVing and never had this happen.

[jondrew55]

Not sure of the way the dump valves are configured on the classics.

First of all, how full does your grey tank indicate? Are you sure there is water in it. Assuming the answer is yes, I'd be inclined to pull the sewer hose off, put something big enough to catch water with under the dump line and slowly open the valve to see what if anything comes out. Assuming nothing comes out I'd run soft plumbing snake or wire or something up into the grey piping as far as it goes. Unlike the black tank, grey tank plumbing is usually not as wide and probably has bends in it. You should at least be able to tell if valve is opened or not. It's possible something made its way into the tank and is obstructing the drain line. Obviously you need to be careful in case it breaks loose and the tank dumps in your face. If the valve is not working, maybe it's some sort of grease build up.

Or you could punt and call a mobile RV tech.

[SMKovalchik]

The gray was at 3% this morning and suddenly jumped to 100%. We know it’s not full because it has some dish water and one shower plus odds and ends. Like every RV we’ve owned the sensors aren’t accurate that’s for sure.

[GCinSC2]

OK here's a SWAG.

The tank was empty all the time because the valve was not fully closed the last time it was drained and then closed. But it was slightly open allowing continuous draining.

When I've oops'ed and over filled the grey it backs up into the shower.

[SMKovalchik]

Interesting thought. It says 100% but as we all know those sensors and gages are inherently goofy. It’s closed so we’ll see.

[rucos]

how about close valve add a few gallons....open again and see what happens. If it still doesnt drain close valve and add a sewer cap with a garden hose adapter... then adapt pressure hose onto cap ...open valve and send some water back into tank. This should clear any blockage fairly quickly .... and you wont end up with a face full.

[rucos]

If you want better monitors add "see-Level" tank monitors which are very accurate .

[Mollysdad]

Back to basics. Is there a puddle under the Airstream? (I assume not)
Add five gallons of water via a bucket or hose to the sink and see what happens.


I've heard of the cable coming off the gate valve, but it seems like it would feel different.
First, make sure there is water in the tank. If it backs up into the shower, then it's really full.
Then I'd try a 1/4" snake and see what you feel.

[Torpedo Family]

I just had this problem but my handle broke at the rivet and had to drop the pan under the trailer to fix it. Had Southland Airstream do the repair but found out there are about 10 bolts that hold the cover on the tanks and I could have fixed myself. Just know that is heavy. Good luck hope it works out it was just not closed before.

[scorpiontimo]

Use the cap and garden hose at the dump valve close the black tank open the Grey valve, turn on the hose 1/2way and see if the flush clears if it backs up in the shower you may have a block in your dump hose or it will clear the blockage if there is one. Cheers

[Mollysdad]

How about this idea? (It's a good addition anyway, because of the handle.)
Replace your cap with this, connect a garden hose, open the grey valve and turn on the water. If there's a blockage, it should push it back. If the gate valve is broken you should see a lot a pressure backing up to you.
I just leave this on mine. The handle makes removing the cap a breeze.

[SMKovalchik]

Well, we hooked a garden hose up and used it to put water into the gray tank from the dump valve side. It seems to have accomplished something. We have a moderate stream now. There’s hope.
Thanks to everyone who made suggestions.

[lemley]

As far as backwashing the tank...

I have a Valterra Sewer Solution. I don't use it all of the time, but in many cases it's cleaner and easier than a conventional stinky slinky and it has the added feature that you can shoot the jet of water back into the tank.

There are similar devices available for dealing with a plugged tank drain, such as the Rhino Flex or Hydro Blaster.

I like the sewer solution because it can serve as a conventional sewer hose (with water driven macerator), it can drive the waste 100 feet away or 3 feet up and it extends with standard 1" PVC. Last time out it was 25' to the sewer hookup. No problem with the Sewer Solution. At home the house cleanout is about a foot above and 15' from the driveway. Again, no problem for the sewer solution.

[scorpiontimo]

Glad we could help no matter how long we rv it we always are learning a new trick or a new solution ��cheers

[hairyclive]

Originally Posted by SMKovalchik

Have looked through topics and haven’t found this problem. We have an ‘18 30’ Classic. Tonight, for the first time, the gray water won’t drain. We closed it yesterday to collect water to flush after draining the black tank. Normal procedure. When we opened the gray valve nothing came out, not one drop. Need suggestions. Of course it’s Friday night so no chance of help over the weekend.

There is the possibility that the tank exit is clogged with hair, grease, dirt, soap scum, or other material from the grey water. You might try blowing back through the exit pipe with some low pressure compressed air to see if this restores some flow. If this solves the problem, it will be a temporary fix; and you will have to remove the pipe from the tank exit and remove the blockage manually, or remove the tank and flush it out completely. Installing screens and other debris traps in all drains connected to the gray water system will help to prevent a reoccurrence of the blockage. Something similar to a restaurant grease trap but smaller and less complicated, installed in the grey water main feed to the tank will also reduce the problems.

https://www.mechline.com/blog/fog/ho...who-needs-one/

[wave man]

One of these cleared my gray tank clog this morning, it's simple and protects from the possibility of the clog clearing and a full tank suddenly pouring out because it can be hooked to your slinky, and you can close the valve on it and fill the tank to rinse/flush it...

I'll be using some enzymes in the gray tank after this, and using a Tub mushroom to catch the hair...

Best Wishes


https://smile.amazon.com/Valterra-De...s%2C165&sr=8-3