Does anyone know what the assembly on the Mainship MK1 on the starboard side where the water hose connects is called? It appears to have a check valve or preasure switch inside of it and is all in one component. Where can I purchase one also?
Yep, water pressure regulator. Far as I know, all the Luhrs Group companies used Jabsco units.
The original regulator in ours was a 35-PSI unit, semi-anemic and we have PEX plumbing... so more pressure seemed doable. Jabsco's more recent 45-PSI unit does work better, although I had to enlarge the cut-out a bit.