Those of you that have this unit in your Newmar be advised the overflow tank was installed on top of the unit, PT tech support
says this is absolutely incorrect. the radiator/tank can't pull back the expanded fluid easily and the system fluid level can get too low.
Guess what that does?
circulating pump runs dry and is toast
So after dropping $425 I found the tank needs to be placed with the top of it even with the unit.
See pic on relocated overflow