Water keeps draining out of the overflow

[ksten]

I'm on my first RV trip and I'm trying to figure out what I'm doing wrong. I filled the water tank full this morning and drove all day. About halfway i noticed water draining out of the overflow tube underneath. By the time i got to my destination, the water tank was completely empty. Is there some kind of valve I need to close so that it won't keep draining the water out? I checked the manual but it makes no mention of this. It's a Triple E topaz 25 ft 5th wheel.

[wa8yxm]

I do not think they put it in my manual either.. I think different serial numbers of the same make and model.. Well they may have different tanks and thus put the valve in different places.

But one HINT.. the OVER FLOW.. is well.. OVER

your problem was "under".

[DrewE]

ksten wrote:
Found it. It was in the compartment behind the 5th wheel attachment.

Strange they never put it in the manual...

Glad you found it.

RV manuals tend to be very generic, though that does vary somewhat with different makers. It may be strange, but it's hardly surprising to me that they didn't have information on where valves etc. are located.

[ksten]

Found it. It was in the compartment behind the 5th wheel attachment.

Strange they never put it in the manual...

[wa8yxm]

The overflow tube is not UNDERNEATH the tank drain however

You forgot to close the drain valve. (or install the drain plug depending on the RV) this is there so you can drain the tank at the end of the season to prevent freeze damage.

[RedRocket204]

Then it is obviously your fresh tank valve that is open.

My trailer fresh water tank has a gate valve that you reach from under the trailer. You pull the gate and watch out for the rush of water 🙂

This video shows a RV fresh water tank that exists under the bed where the fresh water tank valve is very close to the tank, but then plumbs to the outside, maybe this is similar to what you have???

youtube - Rv Freshwater tank drain

Another video with a different valve location - youtube - WNY RV Rental - Sunseeker: How To Drain The Fresh Water

[ksten]

I just tried filling it again and it drains immediately, so there has to be a valve somewhere. The question is where...

[hotpepperkid]

Mine did the same thing although it didn't empty the tank but water did slush out of the over flow so I put a 1/4 turn valve on it.

[drsteve]

A quick Google search reveals that Triple E puts the valves inside the storage compartment aft of the entry door. Look for a knob-style shutoff. Overflow might run through that area too.

[dewey02]

RedRocket204 wrote:
When you filled your fresh water tank, was there water immediately flowing onto the ground from somewhere under the trailer? If not and the water only came out after you were moving, then your fresh water tank drain valve is closed and the advice given about the vent creating a vacuum is what you should be looking into.

x2

[RedRocket204]

ksten wrote:
Yes, the tank drain valve. That's what I'm trying to find. I've looked at the paper manual, and the online PDF manual, but the only mention they have for the drain (even after text searching the whole document) is:

1. Drain the fresh water tank.

Nothing about how that's supposed to happen, or where the actual valve is 😕

When you filled your fresh water tank, was there water immediately flowing onto the ground from somewhere under the trailer? If not and the water only came out after you were moving, then your fresh water tank drain valve is closed and the advice given about the vent creating a vacuum is what you should be looking into.

[Sam_Spade]

bdpreece wrote:
Unfortunately on many rv's the overflow is plumbed in such a way that once it starts to drain for any reason such as sloshing as you go around a corner, it creates a vacuum and can empty the entire tank.

YES. IF the water really IS coming out a vent/overflow line.

My vent/overflow is a little hole right next to the filler neck.

Mine also has a quick drain valve in the bottom of the tank which also could be the culprit here too.

[DanNJanice]

bdpreece wrote:
Unfortunately on many rv's the overflow is plumbed in such a way that once it starts to drain for any reason such as sloshing as you go around a corner, it creates a vacuum and can empty the entire tank. For now your best bet is to plug the drain but don't forget to remove the plug when filling the tank. The correct fix is to find the overflow line and loop it upwards above the tank then down.

What bdpreece said ^^^^
This is a very common issue. I see trailers(including mine) and 5vers mostly doing it while driving down the highway. I suspect because there is little clearance between the top of the tank and the floor above it. Definitely search for the low point drain shutoff first. However, if it turns out to be the vent valves one common solution is to put shutoff valves on the tubes. Then close the valves while traveling. Leave them open the rest of the time.

[Mont_G_J]

I'll offer this has a suggestion. Look on the inside trailer floor directly above where the water is draining. Look for a cutout in the floor and left in place so it's not very noticeable. (in my trailer it's a 5 inch circle with a small hole for my finger to lift up the floor cutout).

[ksten]

Yes, the tank drain valve. That's what I'm trying to find. I've looked at the paper manual, and the online PDF manual, but the only mention they have for the drain (even after text searching the whole document) is:

1. Drain the fresh water tank.

Nothing about how that's supposed to happen, or where the actual valve is 😕