Compressor/Condensor: It is located outside the building and brings air into the air handling unit. The compressor pumps refrigerant gas underhigh pressure through a condenser coil, where it gives up heat and becomes aliquid. The heat is exhausted to the outside air by the condenser fan. Compressors have a service life of 5 to 15 years, depending on the maintenancethey receive, and are the most critical component in the air conditioning system. ADVANTAGE: It can be used in reverse in the summer to cool during warm summer months. DISADVANTAGE: These units are very noisy and should be moved far away from bedroom windows.