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Old 06-28-2019, 02:47 AM   #101
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Originally Posted by doggonecat View Post
by replacing the hoses with longer ones, forming two complete loops after exiting the tank to prevent the siphon from forming.

The new design has a longer hose which coils twice on top of the tank before running to the outside. The added length and coils prevents water from flowing directly through the tube to form the siphon.
Hi, I read another post where someone did something similar, he added a loop on hose after it dropped down thru flooring...

I'm concerned that water would get stuck in lowest point of loop? and would block air flow, defeating purpose of a vent...

For me, I am replacing my single overflow/vent line (bc it was so black inside), it clamps onto a 90' elbow from the side of water tank, and drops straight down thru floor...
I'm currently trying to figure out if it would be better after clamping new hose onto elbow, to just let it hang straight down as before,
or to take it at slight upward angle to the gravity fill port vent line opening (where nothing is attached)??

But if hose leaves elbow and then curves up, even slightly, it could cause a water seal in tubing... like the loops seem like they'd cause...

I only have the one vent line, maybe with 3 as some people have, it's different?

I just want to be able to fully fill my already small tank (30#) and use water for more than the toilet...

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Old 06-28-2019, 10:50 PM   #102
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On my last trip I ran into this problem when filling my tank. I was completely baffled
I then figured that if I was filling the tank to fast it would create a siphon effect and dump 1-3 of my water out.
I did this 3 times when trying to figure out what in world was going on. The last time I just set my hose at about half way open instead of full blast and turned off once I saw overflow spilling.
Before even after I turned the hose off the siphon effect would suck out 1/4 of my water and dump it out.
This finally solved my mystery as to why I felt like I arrived with less water to my campsite then when I left
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Old 02-21-2020, 08:36 AM   #103
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Originally Posted by JRD View Post
Water siphons forcefully from the vent/overflow tube extending through the underside of the trailer when filling the fresh water tank on my new White Hawk 24RKS. It continues after I stop filling and then siphons out much of the water supply.

The small screened vent hole by the filler cap was plugged at the factory and is not connected to the tank.

Why did Jayco decide to go with the arched overflow tube to the underside of the trailer instead of connecting to the screened vent hole by the filler cap? That system worked just fine on my old, cheap travel trailer.

I have both the vent line and two overflow lines. Does anyone know why those overflow lines are even there? (Especially two of them?!?!) With a gravity fill, can't you just stop filling when the water comes back out the fill opening? I don't have a problem with siphoning, but I do have this problem: I want to replace my tank, but none of them I find have any fittings for overflow lines, only one for a vent line. I seems like this would be sufficient, and limit the number of ways that gunk can get into the tank.
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Old 08-21-2020, 09:38 AM   #104
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I have a question I donít see answered here. I have a 2017 27.5 RLTS that loses fresh water from the overflow especially when turning left. There are 2 hoses at the right rear corner underneath. One is about a 1Ē ribbed hose with a rubber fitting on the end to let water out and nothing in and the other is about a 1/2Ē smooth open ended hose. Is the smaller hose a vent? Can I plug the larger hose. I donít think I had this problem till I let the overflow run awhile one day.
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Old 08-25-2020, 07:47 AM   #105
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FYI This is still an issue with a 2020 GreyHawks, very disappointing but an easy fix. On the GreyHawk the tank is skinny and wide. As soon as you turn and put G's on the water (by making a right hand turn) water pores out of the 3 overflow valves on the left hand side of the tank.
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Old 08-25-2020, 07:52 AM   #106
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Originally Posted by slopeshred View Post
FYI This is still an issue with a 2020 GreyHawks, very disappointing but an easy fix.
Welcome to the site from SW Michigan!
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Old 09-13-2020, 07:29 PM   #107
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Hi I have the same problem with a 2019 Jayco HT 25.5REOK. My drain hoses are diff. One is flat and one is 1/2" round and the water comes out the one that looks like a bicycle tube when full and going down the road . Does anyone have a fix for this set up. Thanks Traverler
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