Because it’s the substance that moves heat out of your house, proper refrigerant charge is vital to air conditioner performance and efficiency. In a closed-loop air conditioning system, refrigerant circulates continuously between the evaporator coil in the indoor air handler and the outdoor condenser coil. This highly heat-absorbent chemical changes state from a vapor to a liquid and back again as it extracts heat energy from warm household air passing over the evaporator coil, then transfers it outside for dispersal at the condenser coil. An air conditioner is engineered to operate with a very precise pressurized refrigerant charge. Too much or too little results in a myriad of A/C malfunctions and performance shortfalls.
Overcharging is frequently caused by an unqualified technician adding extra refrigerant to remedy A/C performance problems instead of properly troubleshooting the source of the problem. A refrigerant undercharge usually results from a leak somewhere, or because the system was undercharged when it was originally installed and proper charge was not verified at that time.
Overcharging symptoms include:
- Diminished performance. Capacity to cool actually drops proportionally as refrigerant charge exceeds the specifications for the unit. The system runs longer to meet thermostat settings and uses more energy.
- Reduced comfort. Overcharging increases the temperature of the evaporator coil, causing it to extract humidity less effectively. Household air may feel muggy and warm.
- Compressor damage. The most expensive single component in your system, the compressor can be permanently damaged by excessive refrigerant.
Undercharging symptoms include:
- Diminished cooling. Insufficient refrigerant makes the heat extraction process less effective. The unit runs extended “On” cycles, eventually running non-stop without reaching thermostat settings.
- Coil icing. Ice forms when the evaporator coil drops below freezing, reducing coil efficiency and potentially triggering a system shutdown if airflow is completely obstructed.
- Compressor wear and tear. The refrigerant formula also includes vital lubricant for the compressor. Low refrigerant means reduced lubrication that may cause compressor overheating and eventual damage.
For more information on professional A/C service including checking your refrigerant charge, contact Comfort Systems.
Our goal is to help educate our customers in Wichita, Kansas about energy and home comfort issues (specific to HVAC systems).