u/Independent-Sir-9267

Can a capillary non inverter system be undercharged just enough so it doesnt freeze the evap to achieve lower room temperature?

Hi, new to hvac and mini splits. I have a non inverter mini split that uses capillary metering and I think a rotary compressor. Recently, its not cooling down as best as it can, condenser and evaporator is clean and not blocked. Capacitor and ntcs are in good condition, I've checked.

Question is, how does one determine the refrigerant charge (R410A). I can't recover and weigh. Should I measure target superheat at the intake right before the indoor filter? What psi to charge the refrigerant at suction line? I've seen my country's tech based the charge by looking at the current draw. I don't think that's correct.