Quote Originally Posted by Gary View Post
OR

You can weigh in the charge as marked on the nameplate.

The manufacturer has done all of the work for you, setting up the system under tightly controlled conditions, determining the right charge, and then pulling all of the refrigerant out, weighing it and marking that weight on the nameplate.
At what operating temperature would the refrigerant mass charge determination be most appropriate - startup Tc,sat 35'C; or hot end Tc,sat 70'C?

I have no given mass charge to work off in this case & have to determine it in-house.