r410a Scroll Chiller Cooling Performance Problem-Expert advise please

[RANGER1]

Dear Ranger,

Yes i have a sight glass on the liquid line, i see small bubbles but %90 liquid feeded to EXV

Liquid receiver?

The only things I can think of with your symptoms are,

- System 2 short of refrigerant.
- no liquid receiver or low level in it. Has to have one in my opinion.
- change filter drier to eliminate pressure drop & possible flash gas after it due to little sub cooling.
- Expansion valve open more as starving for refrigerant.
- superheat 7 degC possibly fooling us due to it only being able to get a maximum of that, unless ambient can increase it through heat gain which does not apply in your situation on test rig.
- If system short of refrigerant condenser may behave differently & condense at a higher pressure.

Does not explain higher suction pressure but running out of ideas.