Non draining shower recess

[Jim]

The water is not getting away in my shower recess (motorhome). I have checked the drains (two small ones) in the floor and find that they are clear (as far as I can ascertain by pushing a cleaning rod/wire down them). It was suggested to me that the non return valve may be the problem, so under I went to try and make sense of all the pipes and fittings. There is a large diameter (larger diameter than some of the rubber hoses) sitting way up high - is that the valve? It is a bit inaccessible and the only way to get to it would be with the wheels (dual) removed. But I don't want to face that while on the road travelling (lack of jacks and safety supports). Would a plumber know about these things seeing that it is not a fixed home situation?
Anyone had similar problem?

[BernieQ2]

I doubt if a "home " Plummer would know Jim , but wont hurt to ask one . And if you are concerned about getting under m/H with wheels off just slip them under as safety encase the M/H moves whilst jacked up .
I do this at all times I remove a wheel .
Plus I don't know what M/H you have , mine is all house fittings I done myself so easy to fix .
Bernie .

[supersparky]

Jim, On a few occasions my grey tank has done the same thing. Once it was full and problem solved by emptying. Other time the pipe was gunked up with soap scum. I used a product called Drain Clean. It is only available from Bunnings and it the one with the purple label. Apparently it contains 'Liquid Enzymes'. Just put a cap full down the drain outlet and see what happens. If it is blocked with soap scum it will soften it up and then will be easy to clear.

[Dot]

Draino

[idexnz]

Have you tried using a plunger while the drain is full of water? That often gives blockages a good move-along.

[norman]

The large pipe could be a Hepvo non return valve. they have a rubber membrane in them could be stuck try some really hot water with bicarb in it down the drain

[T1 Terry]

The latest plumber tool for blocked drains seems to be a unit that belts a blast of water and compressed air down the blocked drain. A mix of the purple cleaner from Bunnings and a hit with one of these pressure blast things should clear out all the hair that is blocking the drain/hepvo valave.
While we were away Margaret managed to loose the plug down the silly little bench top sink drain and it lodged itself in the Hepvo valve. No problems for about a week, then the draining got slower and slower.... amazing just what collected around the plug that was stuck in the valve and it had built itself into almost a perfect seal. They are esy enough the get out once you can get close enough to put your hands around the screw on bits at each end and real easy to clean out, way ahead of the old standard "S" bend

[Jim]

All now good. The problem was the Hepvo valve. Really sealed it self. Will look at replacing when we arrive home. Thanks for the advice, guys.