Question Hello + Water tank issue!

[eZAK]

I just joined this forum today even though I been pulling trailers for over 30yrs.

I have a nagging question (maybe problem) we'll see.
What is your folks opinion on the various capacities that are stated in a mfrs. brochure? Does one believe exactly what is printed or are there assumptions to be made ?

My case in point; If it is stated that the Fresh Water is 66 gal., Does that mean I have somewhere close to that amount available for use? Or not?

And Yes, There is more to this story, but I would like your opinion first!

Thank You!

Pat

 

[Neal]

Welcome to RVForums @eZAK. It's best to verify as best as you can, I know my tanks top out at about 10% less than what's published.

 

[TJ&LadyDi]

Welcome to RVF, @eZAK; glad to have you here with us. While I have never measured any of my RV tanks down to the last gallon, they have always seemed to be pretty close to the stated capacity.

TJ

 

[eZAK]

Thanks for having me!

Well what started it off was basically two different weekend trips with our new 2020/2021 Montana High Country 294RL.
It took us two years to decide on this particular one.

Our previous 5th wheel, 2008 Titanium 28E33SA by Glendale, had a 62 gal. tank, w/ about 2-3 gal. unusable.
We (wife, myself, & 2 large dogs) could stay 7-8 days before needing to add water.

With the High Country we lasted only 2.5 days until the pump ran continuously. Which of course started the ball rolling, [so to speak]
(noted, apples to apples, we each took one military type shower b/c of Covid)

Our routine; After flushing, I put about 8-10 gal. in the tank, water heater is full, and gray (2) & black each have 1 gal. plus chem.

Something just doesn't add up!


Pat

 

[Gronk]

Your tank could be like one I had. Don't remember the capacity, but is wasn't a big tank. The vent was installed about 1 1/2 inches below the top so it would not fill completely, and the suction line for the pump was 1 1/2 inches above the bottom. If I recall, the capacity was reduced by about 20 gallons, and the factory said "Too bad, so sad"...... Do you have access to the tank for inspection?

 

[eZAK]

Gronk, I had pondered those same things. I think you may be on to something! Although the 5'vr is stored on my property, I may have to wait until spring.
Snow is predicted for this weekend!

 

[Gronk]

Gronk, I had pondered those same things. I think you may be on to something! Although the 5'vr is stored on my property, I may have to wait until spring.
Snow is predicted for this weekend!

Yea, don't miss the white stuff!! Anyhow, I remembered the quantities..... Tank was a 45 gallon and by time you subtracted the 'not usable' portions we had about 30 gallons total usable.

 

[eZAK]

I have heard back from Keystone. This is their finale word on this;

The "Fresh Water 66gal" in all their spec sheets, "refers to the fresh water System capacity, and not just the fresh water tank"

I wish I would have know to assume this when shopping for a new 5'vr

 

[Gronk]

I would still look at the placement of the vent and pump suction fittings. If you need (or want) to you can put these fittings on it and possibly gain more capacity: https://www.etrailer.com/RV-Fresh-Water/Valterra/RK907.html

 

[J&JD]

You might also consider that during the drive the tank might have siphoned some of its contents through the overflow tube. Many of us have had that problem and have had to redo/reconfigure the overflow system. Some tanks have been known to lose half of their water just moving from one park to another.

 

[Lunge motorsport]

As far as capacity goes...
Many manufacturers rate the additional capacity of the water heater in their claimed figure. Never mind that it requires water from the fresh water tank to push water from the water heater and that that water is unrecoverable unless drained. I have had this discussion with RV dealer service managers who had difficulty understanding the concept.
My capacity was stated at 66 gals, the fresh water tank is 60 gals so the 6 gals in the heater is included. I added an additional 34 gal tank to extend boondocking time.
Cheers

 

[eZAK]

Gronk, Thanks for that info.! I never thought of that.

J&JD, I hear what your saying, very insightful! I would imagine that it is possible for a full tank, but we try not to put more than 5 to 10 gals. when on the road.

Lunge, We're in the same boat. I would be happy with a "Loss" of 6 gal. Instead, I have a loss of 18 gal.

 

[Lunge motorsport]

I don't know your layout but my coach has a rear kitchen and the FW tank is in the underfloor below it. It was fairly easy to add an additional tank in the space below the kitchen sink and run a 1/2'' reinforced poly line to the vent tube of the original tank. The new tank has a separate fill station identical to the original but higher on the coach outside opposite wall. I can fill it and then when the factory fresh tank gets to 1/3 capacity, I open the valve and it drains into the factory tank. A completely passive system and contents are visible from the inside of the coach. There is a photo of the install on page 2 of the gallery. It does add a bit of weight but I accounted for that when I performed my brake and axle conversion by moving the axles rearward and closer together.

 

["EZ"]

You might also consider that during the drive the tank might have siphoned some of its contents through the overflow tube. Many of us have had that problem and have had to redo/reconfigure the overflow system. Some tanks have been known to lose half of their water just moving from one park to another.

I have had this issue with mine. The tank vent is too low or something and it will actually siphon water out of the tank if I over fill the tank and get it started out the vent. It just keeps on syphoning water out. I bet I lose 10-15 gallons.