Bleed the air and humidity in the refrigerant circuit. Take out the caps from your two-way and 3-way valves and from the assistance port and connect a vacuum pump hose towards the company port. Take a look at each of the valves and joints for leaks, then disconnect the vacuum. https://brooksbuhvg.tinyblogging.com/air-conditioning-installation-north-west-fundamentals-explained-70235234