Undercharging or overcharging an HVAC system with refrigerant can lead to reduced system efficiency, increased energy consumption, and potential component failure. Undercharging can cause the compressor to work harder, leading to increased energy bills and premature wear. Overcharging can cause liquid refrigerant to flood back to the compressor, resulting in damage to the compressor and other system components. In both cases, the system’s ability to cool or heat the air is compromised, leading to discomfort and potential health issues for building occupants.