Grey water problem

[oakie47p]

We have a 2015 Forster 3011ds,we have problems with our grey tank sometimes the water goes down sometimes it all comes back up in shower.We have called the dealer,they will get back with us,they said maybe we have 2 grey tanks. Craziest thing ever.if I put the jacks up on one side it will usually drain but when I level it back up,backs up again only sometimes..Any ideas what to try? We are 6 hrs from dealer,it would be jarred loose by then anyway,prob.TIA

[John McClain]

I have two grey water tanks , I think you have a vent problem . Fill the grey tank up all the way using the shower . than pull the grey tank handle the water should come out steady and should not be stopping and sucking air like if you tipped over a milk jug, If its thring to suck air you have a venting problem.

[John McClain]

Also check if you do have two tanks one galley tank and one tank for the shower and bathroom sink . you should have to 3 dump valves if you do

your Grey water tank should be around 39 gallons from what I read

[oakie47p]

We only have 1 tank. I can't fill the grey tank,shower stopped up,all running water gathers there..Where would vent be?

[ATVer]

The grey tank vent is on the roof and is common with the black tank. I know it doesn't sound like a good idea but that's how they are made. Sounds like you likely have a clog in the drain line to the grey tank. I found a big wad of masking tape restricting flow in my unit. For it to backup in the shower you either have a full tank (should see that on your level monitor) or the drain line is common with the sink drains. You could check the waste water diagrams to see if that is true. I have diagrams for my unit but I can't tell what you might have since I have a 3120.