26rr fresh water tank question

[Jeramy]

I have a 16 26rr. I put water in the fresh water tank tank most of it drained back out of a white hose coming from the tank area. There's a low point drain hose and a white hose coming from the tank area. Is the white hose a overflow or should there be a valve on the end of it? I haven't crawled under to investigate but I figured someone else knows. Thanks

[16grey]

Yes it is the over flow tube

[rmac04401]

Most have put a valve on it because it will actually Siphon off the water for gravity. They got last and instead of putting vent pipe up by the fill hole like they use to they just dropped there.

[Jeramy]

Thanks for the replys. I figured that's what it was. I guess I'll put a valve on it and make sure to open it when I fill the tank.

[Kimber45]

that is exactly what i just did. found a barbed fitting to go into the tube with a hose clamp and the other end is threaded and took a standard plumbing cap. about a 2$ fix.

I lost about 1/3 of a tank my first trip out in my new unit due to the siphon effect. had never had a problem on my other units? Just gotta remember to open while filling then cap off when done.

[zuterbru]

I lost 2/3 of my fresh water first trip myself. I noticed some water trickling out but I always saw that on my last rig from the vent tube. Got to camp, 1/3 fresh water tank. I thought the gauge was messed up, nope, then found out in here about the siphoning. Have a shut off valve on it now, planning on running up the vent hose when I get a chance.

[Jeramy]

That's exactly what happened to me. Putting a valve on this weekend. Wish I knew before we left.