PMDG 737: Hydraulic Electric Pumps - Overheat

[Portalearth420]

@FormerSnail5736

If the center tank contains more than 453Kg of fuel, the wing tanks must be full. NEVER have fuel in the center tank unless the wing tanks are full. Bad bad.

Can you elaborate on this? Is it a balancing thing or just how the fuel system is supposed to work?