Central air conditioners are built to keep refrigerant sealed tight. In fact, the coolant should outlast the the air conditioner in most cases. However, there are rare situations where refrigerant can leak from and need a recharge – or more accurately, a refill. Leaks are often caused by damage or a manufacturing defect. In many cases the manufacturer will cover repair of the leak under warranty.How Refrigerants Work Refrigerants are used to extract the heat from the air, without this heat transfer the AC will fail to cool, so the most obvious sign of a coolant leak is when the air begins to feel warmer than normal. Of course, this will also trick the thermostat so you will also notice that air conditioner running more often. This will happen gradually over time as the refrigerant slowly leaks out of the coil. Another sign of a refrigerant leak is a buildup of frost and ice on the surface of the unit. When exposed to air refrigerant is a gas that will freeze on exposed surfaces.If the system does need a coolant recharge, the work should be performed by a qualified air conditioner technician who is certified by the EPA to perform the work. Annual AC maintenance is also important to find small leaks before they lead to problems. If the air conditioner is 12 years or older, it may be more cost effective to simply replace the air conditioner with a newer, more efficient model rather than repair and refill unit.Have questions about your air conditioner? Call Gibson’s Heating and Plumbing, we’re here to help.