Water Tank Hookups?

[MommaFos5]

Hey guys! I could use some help. I am trying to figure out the purpose of these three hook-ups to our water tank. I’m assuming this tank is original to our Burro, but can’t be sure. We bought it, as is, with only the one hose hooked up to it. I’m thinking that one is for water intake, one is for the water to be pumped to the sink, but what it the third? A type of burper, perhaps??

[Steve L.]

Water tanks usually have three connections.

A fill at the top.

An exit to the water pump near the bottom (generally self priming) which could be at the top if there is a tube inside the tank so that the pickup is near the bottom. An extremely awkward way of plumbing.

An overflow, also at the top and often routed to the vicinity of the fill door.

The inlet is usually much larger diameter than the overflow.

[mszabo]

Overflow/vent as Steve said. It will usually pipe back to the fill, which has a vent outlet.

https://smile.amazon.com/JR-Products...s=Rv+fill+vent

[k corbin]

Originally Posted by MommaFos5

Hey guys! I could use some help. I am trying to figure out the purpose of these three hook-ups to our water tank. I’m assuming this tank Attachment 119813is original to our Burro, but can’t be sure. We bought it, as is, with only the one hose hooked up to it. I’m thinking that one is for water intake, one is for the water to be pumped to the sink, but what it the third? A type of burper, perhaps??

That tank will lie with the openings on the side. The largest opening is closest to the top. The largest opening is where you attach the fill hose. The other small opening towards the top is where you attach the vent hose. The water won't pump out unless there is a vent, air has to be able to enter to replace the water you pump out, (otherwise the container would have to be able to collapse to squeeze the water out of it). The lowest opening is where you hook up your pump to take water to the faucet.

[peterh]

Our Scamp 5er vents out the bottom of our trailer, but we bought a fill port for our Surfside project trailer that has a vent built in, so where the vent line goes depends on your setup. But, yea, the air needs a way to escape as you fill the tank.

I cut off a piece of a Scotch Brite copper coated scrubbing pad and stuffed it into the exposed end of the vent tube under the trailer to prevent vermin from climbing up there and blocking the vent.

[Wayne Collins]

There may also a tank drain port. Or, the outlet to the pump may have a drain cock in line.

[Tom 72]

I am learning here. So the vent tube or pipe. What keeps insects from crawling up it? Is there a screen? Thank you.

[Borrego Dave]

Originally Posted by Tom 72

I am learning here. So the vent tube or pipe. What keeps insects from crawling up it? Is there a screen? Thank you.

Tom, all the RVs I've had had the tank vent hole next to the filler inlet behind the tank fill door. Never had any problem with insects...that I know of. If the vent tube was run through the floor and open ended, a bit of screen over the end would fix it. IDK, maybe in the scope of things, that may be a 1 out 100 to worry about .

[peterh]

Originally Posted by Tom 72

I am learning here. So the vent tube or pipe. What keeps insects from crawling up it? Is there a screen? Thank you.

In the case of my Scamp 5er, nothing. That's why I pushed a piece of ScotchBrite copper scrubber mesh up the tube. It won't keep the tinyest in the bugs from invading my fresh water tank, but it will keep things like mud daubers and other bigger buggies out. That said, I may have done this out an abundance of caution. I haven't heard anyone on FIberglassRV complain about bugs in their fresh water system.

[peterh]

If you're refurbishing/upgrading your trailer, there are plenty of fill ports on the market that block the fresh water vent tube when closed. That's what we've installed on our SurfSide project trailer.