You have an extraordinary amount of JG corner connectors, and from the very crappy pic it appears to end up almost exactly where it started.Just reactivating this thread, I have set up my inlet system as per @Crusty181 and it has worked fine. But while we were away I was on mains water at a site and found my rear tank was filled up and overflowing through the breather. The tank selector was set to the rear so I doubt the problem was tank selective. It would appear I have a non functioning Non Return Valve but I am unsure (read, I haven't a clue) where to find the NRV. Tracing the Jayco water lines is like trying to pick winning Lotto numbers but my best guess is the one in the picture.
View attachment 57104
Excuse the lousy pic as I was hanging upside down under my bed to take it. The valve appears to match the valve shown from Coast to Coast here.
Is this what I need to change?
I think you missed a significant spec in that manual link;I managed to take a better picture today but I discovered other problems.
View attachment 57148
I looked up the manufacturers sheet and here is part of the info. It is a Shurflo 4009-101-A87 and full instructions here.
INSTALLATION GUIDELINES OVERVIEW
Mount on a solid surface within 1.8 meters (6 feet) of tank
Minimize flow restrictions in the system
Minimize plumbing elbows and valves
Connect flexible hose on inlet and outlet
Affix strainer on pump inlet
Properly sized plumbing
No accumulator needed
Properly sized wiring
Proper electrical protection
Accessible location for occasional strainer cleaning and maintenance
The items in red are where Jayco has not followed installation instructions thereby voiding any warranty I may have had with the pump. There is no filter, there are no flexible pipes on the inlet and outlet, there are 8 elbows and tee junctions just on the pump and the only adjustment to be made is on the end facing the wall where you can't see or access it.
I think I will be reversing the pump, fitting flexible pipes plus a filter. Then I may be able to adjust the pressure as per the operation sheet.
I wasn't sure of the fitted size but you're right.I think you missed a significant spec in that manual link;
Plumbing must have a minimum Inner Diameter of 13mm [1/2”]. Smaller ID plumbing will cause cavitation, high backpressure, low flow and noise.
John Guest air fittings Jayco use are 12mm external
Proabaly a coincidence, but I swear my pump's cavitation and noise was less before reading your postsI wasn't sure of the fitted size but you're right.