The function of a capacitor in a fan is to store electrostatic energy in an electric field and where possible, to supply this energy to the circuit. The role of a capacitor in a fan is to prevent a dangerous failure of the circuit, they allow the AC to move but block the flow of DC. A condenser, also known as a capacitor, is used in a fan to help regulate the electrical current flowing through the mot. The function of the condenser in a refrigeration system is to transfer heat from the refrigerant to another medium, such as air and/or water. By rejecting heat, the gaseous refrigerant condenses to liquid inside the condenser. A condenser is an essential component within any HVAC system. Its purpose is to take in high-pressure refrigerant gas, emitted by the compressor, and convert it into liquid state. The refrigerant is cooled and then condenses at a virtually constant temperature and pressure. A capacitor can help a fan motor to run at a higher speed by helping to regulate the current flowing through the motor. A capacitor is connected to the start winding in a Fan. In low power induction motor like fan it is left connected permanently, so as the capacitor ages speed of Fan reduces.