Fresh water tank leaks near top

[imolared]

First trip of the new year.
2019 3120RL

I filled the fresh water tank to discover a serious leak towards the top of the tank.
After the dripping halted, I measured the amount of water in the tank. It was about 55 gallons. The spects of the fresh water listed the tank as 66 gallons. So I figure the leak is about 84% the way up the tank or 16% the way down.

The leak is at the back driver side, near the overflow outlet. The leak is only from the underbelly paneling.

The weeks before filling the tank there were some very cold 14 deg F. nights.
Just wondering if there is some “pipe” near the top of the tank that may have had water that froze and made a crack?

I have removed some the of nail rivets that secure the paneling attempting to look, but not knowing how it all works there I stopped.

Looking for your advice. Having some photos of what it looks like would be GREAT.

[Daryles]

Coroplast removed.
This is from the ground looking up.
Drain fitting on the left (semi circle).
Fill/pump supply is the White hose.
The White corrugated pipe is the vent.
You will need to drop thar corner of the coroplast to see what's going on.
While you have it open reinforce the supports underneath.
The specs say 66 gallons of freshwater. This is the freshwater tank 50, the waterheater 12, and the plumbing 4.

[imolared]

Very interesting!!!
Using 7-gallon water container "Reliant" I filled it 7 times plus almost #8 so I figured 55 gallons. I do not believe that the freshwater drain will also drain the hot water tank. So I am concluding that the leak might be the connection of the corrugated pipe to the vent

[Rondo]

Daryl's figures are correct and the manual postings include the tank volume, the hot water volume and any water that might be in all the lines throughout the unit. The tank total volume is not the 66 gallons. I don't know what tanks you have in your 2019 unit but if they are the older style tanks that the top is welded to the main body of the tank there have been problems with tanks having a crack or error in the main section just about where you are describing. We had one of our gray tanks replaced and when the dealer filled it to check it they found the problem. They had to have the tank plastic welded by someone who knew what they were doing welding plastic. This tank was new coming from Keystone so they got a bad batch of tanks in on their order from the manufacturer. I never fill my fresh water tank full especially when traveling and very seldom when parked because of the weight and the way the tanks are supported. JMHO

[Daryles]

I found another picture someone posted. They had a leak where the freshwater tank vent connected

[RMcNeal]

I also have a 2019 model and the tanks are all supposed to be the roto molded ones, not the two piece. I have not confirmed this with my own eyes, however. I'm betting the leak is coming from either the vent hose or the fitting that it connects to the tank.

[Carl n Susan]

Originally Posted by Rondo

...I don't know what tanks you have in your 2019 unit but if they are the older style tanks that the top is welded to the main body of the tank there have been problems with tanks having a crack or error in the main section just about where you are describing....

The fresh water tanks are made of different material (white polyethylene?) than the sewer tanks and much more sturdy in construction.

[bcrvman]

Originally Posted by imolared

Very interesting!!!
Using 7-gallon water container "Reliant" I filled it 7 times plus almost #8 so I figured 55 gallons. I do not believe that the freshwater drain will also drain the hot water tank. So I am concluding that the leak might be the connection of the corrugated pipe to the vent

Correct, to drain the tank, change your knobs to bypass and remove the anode to drain. Good time to flush the tank with a flushing wand and replace the anode.