Fresh water tank

[accumack]

Does your fresh water tank inflate when you fill it? My tank appears to bulge the top of the tank when i fill it. I'm wondering if my vent is blocked.

[trekdave42]

I had the same problem! It all depends on the way it's filled from my perspective. I filled it once with 270 degree adapter and guess it put a lot of air in the tank. Recently, I removed the adapter and hooked the hose up directly. Checked the tank afterwards and no bulging. Hopefully this makes sense.

-Dave

[Phil57]

Mine always bulges up. I figured I was getting extra capacity. I don't know if it's right or wrong but it has always done it.

[accumack]

I was sanitizing the system to get back on the road and when I went to the bay the tank was expanded to where it was touching the black and gray water tank. When I drained it it went back to almost level. I was worried it was just mine.

[JTN8]

Mine does it too, when I dry camp I actually let it fill all the way until it comes out the overfill/air vent.

Jason

[KennyGolub]

Add me to the list. Mine did it, but I tried filling it slowly the last time and no air bubble.
Unfortunately, I have discovered I have a small leak in either the tank or one of the lines between them.

[I-RV]

X2 on the bulging tank. My tank has a overflow hose attached about 80% up on the side wall of the tank. The hose turns up and then makes a loop downward and pokes through the compartment floor. When the water reaches the outlet fitting (80%full), water does not come out the overflow. But when the water bulges the tank and reaches the top of the overflow loop, siphoning starts and the water continues to drain until it goes below the drain fitting. I was startled once when filling my tank and not paying too much attention; I saw water coming out the overflow. So I shut the water off and then why water kept pouring out the overflow. I then investigated and saw where the top 20 gallons siphoned out - LOL!!!

Another problem is that the hose fitting to the pump is about 20% up on the sidewall. This is a very poor design. It means that you need to carry that bottom water around all the time and not be able to use it. This means that because of the design, 167 lbs. of unusable water is being carried.

A more vertical tank with a bottom outlet would be a better design, such as in my previous class-C.

[Campin Cajun]

Same here, bulges when filled all the way. It's not a problem or concern if it's not leaking. My over fill line is not clogged.

[accumack]

I experimented while i was flushing my tanks. I found if I don't turn the pump on and open one faucet the tank doesn't bulge when it is filled and water doesn't come out of the faucet while filling. I just thought you guys would like to know.

[dan-nickie]

I have always watched my closely and stopped right before it got to the top. I didn't know what would happen after that.

[I-RV]

The water tank is semi-ridged. The bottom is supported by the floor, but the top has no support except for the edges. So when you fill it, the water fills its full volume with the top bulged - sort of like a balloon. After the water fills the maximum volume, it starts up the overflow hose and if it gets to the top of the overflow hose loop, it will siphon your tank to about 80% full -thus loosing all that precious water you put in.

[15berkxl]

Originally Posted by I-RV

The water tank is semi-ridged. The bottom is supported by the floor, but the top has no support except for the edges. So when you fill it, the water fills its full volume with the top bulged - sort of like a balloon. After the water fills the maximum volume, it starts up the overflow hose and if it gets to the top of the overflow hose loop, it will siphon your tank to about 80% full -thus loosing all that precious water you put in.

I keep reading similar posts another bad design? With parts of the U.S. with a water shortage why in the world would FR design such a system to dump on the ground 20% of a precious commodity to many? Or better yet why don't they fix it?

[Phil57]

Originally Posted by 15berkxl

I keep reading similar posts another bad design? With parts of the U.S. with a water shortage why in the world would FR design such a system to dump on the ground 20% of a precious commodity to many? Or better yet why don't they fix it?

I've had mine for three years and yes the tank bulges but we have not had the syphon issue. It's not a huge issue. The only time I have had any issues with the water tank was when I forget I was filling the tank and it got pretty full. Oops

[accumack]

I didn't have a siphon issue either.

[Campin Cajun]

No siphon issue here either.

[JTN8]

Me either

[I-RV]

Unless FR redesigned the water tank over-flow from what my 2012 has, the siphon issue only occurs if the tank is filled to the top (where it bulges) and beyond to the point where water is coming out of the over-flow.

At least on my MH, once the water comes out of the overflow, it continues to siphon the tank down to the over-flow fitting on the side of the tank.

Therefore, if you never filled the tank to have it over-flow, then of course you didn't have an over-flow issue.

[Campin Cajun]

I'll try to get mine to siphon once I get home and report the results.

[I-RV]

Originally Posted by Campin Cajun

I'll try to get mine to siphon once I get home and report the results.

Appreciate that, it may prove my sanity or insanity. I used the over-flow method of filling the tank once, since I hate crawling on the ground for the water compartment latches, having to prop up the door and then crawling on the ground to insert the latches. So I merely filled until water started to come out underneath and then new it was filled. But then a surprise, the water kept coming out even after shutting off the supply.

[CAT-RN]

On mine when new it would overflow. I just raised the overflow tube to the top of the compartment. I then drilled a couple 3/8 holes in the compartment floor. Thus giving me those holes plus the one the overflow tube came out of for any water that might get in there a place to get out. I can fill tank 100% no syphoning.

I don't understand why FR put that crazy door on the water compartment with silly latches on the underside??

I cut a 6" round hole in the compartment wall in front of the water tank. The hole has a screw in plug if one would want to use it. I just open the compartment door in front of water tank and watch the tank fill. Thus never overfilling. I ll attach a picture. Picture will show water tank on other side of wall. Tank has maybe 2" of water in it.

Russell