Issues with fresh water system, andersen kantleak on a 2016 308bhts

[seabass]

Hello,
We just recently bought a new to us 2016 308bhts TT. Got her out to a campground and noticing some issues with the fresh water system,
1. when I turn the kantleak system to city fixture, tank access shut, water heat normal, there is no water pressure inside, water keeps flowing and fresh water tank overflow keeps draining water. (in this state, if I turn on water pump, I have water pressure.)
2. the water tank overflow drain would start draining before I fill the fresh water tank full, at about 1/3. basically the only time it does not drain is when I am in dry camping mode.
3. when I am in dry camping mode, no matter how long I leave the water pump on, it would not be presurized well enough to stop and it keeps pumping.
I am thinking this may be the combanation of a bad check valve on the water pump and a failed andersen kantleak valve. Any ideas on how to replace the kantleak system?
Also, what does the fresh water tank access valve do?

Thanks a lot!~

[Jkwilson]

The Kantleak system is pretty good when it works. Very sensitive to turning knobs while the system is pressurized. They came out with a vastly better, solid brass version which you maybe able to order as a replacement. I have one as a spare I carry with me on longer trips and it magically keeps the original working.

The way the tank overflow is plumbed, I can’t imagine any possible scenario where it could drain before the tank is full. My guess is the tank is full when it starts flowing.

The pump not working could be many things. Just be sure you give it a chance to clear the air from the lines and that you check the screen in the pump for debris.

Here is a link to Anderson Brass RV products. There is a minor plumbing difference between the new and old panels, so make sure you are aware as it will fool you.

https://www.andersonbrass.com/rv-solutions

[TucsonJim]

Cate&Rob - Has some great documentation for repairs on a Kantleak system. Maybe he can weigh in here shortly.

Jim

[Cate&Rob]

seabass

From a design perspective, the Anderson Kantleak system is superior to the other competitors that need multiple valve to do what Kantleak does with one. Another benefit is that the water heater bypass does not need a check valve on the water heater outlet which commonly fails on the other systems. The fresh tank access allows you to fill the water tank while using city water in the rest of the RV.

Anderson's downfall was changing from brass to plastic on their main valve body. I understand that they have gone back to brass, but Grand Design moved on to Nautilus systems. The Kantleak system provided to Grand Design in the timeframe that yours was built, also had a problem with a plastic T between the 4 way valve and the water heater bypass developing a drip leak. If yours is doing this, we can find the procedure that I developed for solving this with a brass T.

The 4 way valve operates with a cartridge that is as easy to change as a residential faucet cartridge. It has multiple O rings that get pushed out of position if the valve is not handled "gently". Pressure must always be released before changing the valve position and it is best to always move the valve in the clockwise direction.

From your description you may also have leaking check valves in the pump. I would change the Kantleak valve cartridge and install a new water pump . . . and your system should function correctly.


Rob