Puma vent problem

[2016Midnight]

Has any had grey water problems with their Puma 32RBFQ (or similar)? I'm have a problem with water backing up in the shower (while showering and while draining a sink). My troubleshooting has identified the problem being the grey tank is not vented. I cannot see where there is a vent connected to the tank. The grey roof vent connects to the drain line between the kitchen and bathroom. The black roof vent goes directly into the black tank. There is a small chance that the black vent T's under the subfloor and also connects to the grey tank but I can't confirm without cutting a hole. Assuming it doesn't exist, I don't know if this is an error in construction or a design flaw.

I contacted Palomino a week ago. Someone was supposed to get back to me in 2 days but I still haven't heard anything.

Thank in advance for any insight/experience you can pass along.

[heliwrench]

I have an '18 Puma also. I haven't had this issue except when the grey tank was getting full. If you haven't solved it yet, I would isolate the issue by opening the grey valve next time you have full hookups, and see if your problem disappears when showering etc.. this would confirm your suspicion- or if it still drained poorly, you could look at your drain pipes.
It wouldn't surprise me if they plugged it or never hooked it up. I have found some weird things with mine that were missed entirely and I had to fix. I have fixed all the issues myself but they have provided decent tech support. hope you get yours sorted out.
Gary

[GuyBonin]

If you are still having issues. There is a vent pipe teed from the drain pipe under the bathroom vanity it has a vent cap one way vent valve on top sometimes they will plug or close off keeping the sink or shower from draining properly.

[cavie]

See if you have access to under the shower. Some rigs have in inline one way drain. It has a flapper. I can't remember the name of it. There is no p-trap under the shower. Might be a problem there. The gray tank is center.

[2016Midnight]

Thanks for the responses. Turns out it was an improper build. Forest River picked up the camper took it back to the factory around Thanksgiving. They had to remove the shower and put a new vent pipe in the wall behind the shower and up through the roof. I verified that fixed the problem then re-winterized. Going to take the camper out of storage this week and get ready for our first outing of the season next weekend.