Replacement units are components used in mechanical services, particularly in heating, ventilation, and air conditioning (HVAC) systems, that are installed to replace older or worn out equipment. They can include entire HVAC systems, specific components such as air handlers or condenser units, or smaller components like motors, fans, and capacitors. The installation of replacement units can help improve energy efficiency, indoor air quality, and overall system performance. They also play a key role in maintaining the longevity of HVAC systems and ensuring their continued safe and effective operation. When choosing replacement units, it is important to consider factors such as compatibility with existing systems, energy efficiency ratings, and performance capabilities.