What does this valve do?

[Becky B.]

While on vacation, my potable water tank started leaking. I couldn't get the access panel off because the screws were so corroded. I decided to try to see what was going on from the top down. I took off a piece of what appears to be lead sheeting to peer down by the tank. While I couldn't fix anything from up there, I did see this valve on the left hand side of the picture. I can't figure out what it does. It continues out the bottom of the trailer (as pictured in the last picture..the grey colored tube behind and to the right of the water drain). I did put a new drain in while on vacation, since I could get at that without removing the panel on the bottom (although that wasn't the problem--the bottom drain was). But anyhow, what does the valve in question do?

[overlander63]

That's a drain. You would open it to let the water out for winterizing.

[HowieE]

Yes a drain. This type of valve is Turn and Lift to open and turn and push down to close. The turning is just to reduce the friction as the valve starts to move not a treaded shaft.

[Becky B.]

The strange thing about this being a drain....it was under a piece of lead sheeting that was nailed down. It also had insulation over it. I filled my fresh water tank & turned the valve, but nothing happened outside. There is a drain on the outside of the fresh water tank. Would this be a drain for the lines in the trailer? Why would they put it under all of those things?

[HowieE]

I doubt the factory installed the lead. Most likely a PO did that to keep out small critters.

If it is a drain for the system you would have to open the faucets and brake the vacuum to drain the system.

[Becky B.]

Makes sense. Thanks for the replies. I think I'll reseal it with something that's a bit easier to remove!