Originally Posted by camlivy
We have an Interstate 2014.5 for almost a year. We haven't tried showering in it yet but I did use the sink nozzle to wash the floor there by discovering that the floor drain fills to the top and does not drain any further. Does anybody else have experience with this issue or suggestions as to what it might be?I appreciate your help.
First rule of troubleshooting, check the easy things first. So, easiest thing, is your gray tank full?
For information only— there are no P-traps in an Interstate, instead there are check valves in each drain (except the toilet) that prevent water from backing up. They're called Hepvo valves— that's a brand name. (Hepvo Waterless Valve
) But they have one quirk. If the Hepvo valve is open to drain water when the gray tank reaches the point of overflowing, the weight of the water above the valve holds the valve open. So unlike the Airstream trailers with P-traps, if you were to fill the gray tank to overflowing while running the galley sink, the galley sink would back up but the shower wouldn't.
So in your case it's possible that you just happened to fill the gray tank to overflowing as you were washing down the shower.
If that's not your problem, then the next most likely thing is construction debris (excess sealant, whatever) blocking the drain. Especially since you've never used the shower before. But the Hepvo valve creates a problem there, in that you can't just fish the drain with a plumber's snake or you'll damage the valve.