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what is mean a condensing unit?Condensing unit are wildely used in HVAC&R . They move energy in the form of heat by compressing a gas known as a "refrigerant," then pumping it through a system of coils and using the air around the coils to heat and cool spaces. In theory, a refrigeration system is consist of 4 parts: Evaporator, condenser, compressor,expansion valve.But actually we w...