A building's or vehicle's interior air is heated by evaporators, which are part of air conditioning systems. By passing refrigerant through a coil or array of coils, an evaporator operates. As the air moves over the coils, the refrigerant absorbs heat from the air, chilling it. After being discharged into the condenser to dissipate heat, the refrigerant is then returned to the AC (air conditioning) compressor for recompression. Since it can more efficiently collect heat from the air within the structure or vehicle, the evaporator is often found there. The effectiveness and efficiency of the air conditioning system are strongly related.