I guess the real question is if anyone is inspecting these packaged units?
Simply using listed pumps and heaters does not insure that they are properly bonded, conductors sized correctly and that they have the appropriate motor starters etc.
I would think a major brand is going to take the time to do things right but a lot of these things are assembled in an industrial bay somewhere by a company nobody has heard of, with minimal supervision.


Greg Fretwell