Replace KankLeak or Nautilus with Matheny System

[2825Matheny]

Moderator note: This post is lifted from the https://www.mygrandrv.com/fo...ing-P1-rebuild thread. To comment please post there.

When we got our 2016 ST369RL almost 4 years ago we almost immediately had two Kan_Leak valve failures. After several conversations with GD they were more than helpful and even offered to ship me a new Nautilus P1 assembly that could be exchanged for the Kan_Leak assembly. So, before I committed to that I dug in and started doing some research. The more I learned about the 5 functions that a water system on and RV is supposed to be able to perform and analyzing the complexity of both the Kan_Leak and Nautilus P1 systems, I called GD and said, thanks, but no thanks. The Natilus P1 is just too complex for the simple tasks that it is called upon to perform. There are too many opportunities for leaks and failures, it is just not robust.
I engineered and installed an entirely new water system. Being an engineer, I took the route to look for the best and least complex solution that was user friendly, the least likely to leak, and easy to operate and understand by just about anyone. Thus, I "invented" the Matheny System. I set out by using parts and components that were readily available off the shelf that were not unique or special so if I did have issues down the road it would be maintainable. One other objective was to remove all of the TS-25 flexible blue hose and replace it with PEX to ensure the system was leak free.

I get your fascination with the "manifold" approach. But, I will say that an RV water system is more simple than that and installing a manifold will require the addition of many feet of PEX to get from the manifold to the user points which will also require dropping the Coroplast belly sheet to gain access to the belly space to add the extra PEX. And as Rob said, it will not do anything to replace the Nautilus P1 assembly. A distribution manifold only is used for getting water to go where it's supposed to go AFTER you select where is coming from and how it going to be propelled (pump or hose).

I have added photos to this post and here is a link to my Google Drive Folder that has just about everything anyone would ever need to duplicate what I have done. So far, I know of two other GD design owners that have done this too and they confirm it is a good system.

https://drive.google.com/open?id=0B1...UZLdTNFWk8xV0E

This is how I would teach someone how to use my "manifold valve" setup. 1st I would ask them "where is the water coming from, tank or hose?" If from the hose then open the bottom left valve. If from the tank then open the bottom right valve. 2nd I would ask them, "where do you want the water to go, pump or fixtures? If to the pump, then open the top left valve. If directly to the fixtures, then open the top right valve. If after they determine where the water comes from and where it is going to, and have adjusted valves, I would say that if a top valve that is open is on the opposite side of the bottom valve that is open then open the crossover middle valve too. That's all there is to it.

I have been using this for 3 years and it is pretty much bullet-proof from failures and it really is simple to use.

One of the two "mods" I added was the addition of a 2nd water filter housing. This 2nd filter ensures that water is filtered right before it goes to the fixtures. (see schematic) I found that water from the fresh water tank had a "plastic"odor to it. This 2nd filter does the trick to remove any odors. When I am hooked up to a hose supply, the the water gets filters twice before delivery to the fixtures and it protects the next mod, a water softener.
The other mod I did was to add a fully automatic water softener just like what would be in a sticks and bricks house, only it's smaller. Having soft water has been great to eliminate water spots and "crud" that built up around fixtures and soap and shampoo actually foam up now.

I approached GD to ask them if they wanted to commercialize this, but since it was "home-made" they said no. They wanted something that was already commercialized and that is why they use the Nautilus P1 today.

[howson]

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