HVAC chiller is a key component of many commercial and industrial cooling and refrigeration systems. A chiller is a machine that removes heat from a liquid via a vapor-compression . Industrial chillers are generally installed in a mechanical equipment room, beside an industrial process, or outside the building. Residential HVAC chillers can be installed in a storage tank next to the home. Chiller system changes the physical state of refrigerant to transfer heat from one area to another. The laws of pressure-temperature relationship state that increased pressure on a refrigerant increases its temperature while decreased pressure lowers its temperature. As the refrigerant circulates through the HVAC chiller, various components change its pressure and temperature, causing it to boil into a gas and condense into a liquid. During the change of state from liquid to gas, the refrigerant absorbs heat, and the refrigerant releases heat when it returns to its liquid state.