Measuring the pressure on the charging port of your heat pump can give you some indication of the refrigerant's state inside the system, but it's not a definitive method to determine if your heat pump has enough R32 refrigerant.
The pressure of the refrigerant in a heat pump can vary with factors such as ambient temperature, load conditions, and the state of the refrigerant (liquid or vapor). To accurately assess the refrigerant charge, you need to consider both the suction pressure (low side) and the discharge pressure (high side) along with the corresponding temperatures.
For a precise evaluation of the refrigerant charge, it is best to use a set of gauges specifically designed for measuring refrigerant pressures in HVAC systems. By comparing the pressure readings with the manufacturer's specifications for your specific heat pump model and the corresponding outdoor and indoor temperatures, you can determine if the system is adequately charged.
If you suspect that your heat pump may have a refrigerant issue or is not cooling/heating properly, it's essential to contact a qualified HVAC technician to inspect and service the system. Only a certified professional can accurately assess the refrigerant charge, identify any leaks or problems, and perform the necessary repairs or maintenance. Additionally, improper handling of refrigerants can be hazardous and is best left to trained experts.