According to recent reports, there is an abundance of units that show symptoms of not cooling, freezing and so forth.The homeowner's ac unit or heat pump has actually been overcharged. If your unit is not cooling, we have instruments that can measure superheat and subcooling temperatures and make sure the unit is charged to manufacturer's specifications. Overcharging a unit can shorten the life. If your unit is cooling well, it does not need to have the refrigerant tinkered around with. It does need to be inspected, filters changed regularly, airflow checked, wiring checked, volts and amps, evaporator condensation clogs and leaks, and others.