Compressor Mechanics: Ductless Mini Split Installation Explained Thoroughly

The compressor is a vital component of a ductless mini split system, playing a crucial role in the cooling process. This article provides an in-depth explanation of the compressor's role, its types, and the steps involved in its installation. Understanding the compressor's function and the intricacies of its installation can help ensure the efficient operation of your ductless mini split system. This knowledge can also aid in troubleshooting and maintenance, ensuring the longevity of your system.

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Compressor: Ductless Mini Split Installation Explained

Understanding the compressor's function and the intricacies of its installation can help ensure the efficient operation of your ductless mini split system. 

Understanding the Role of the Compressor


The compressor is the heart of any cooling system, including the ductless mini split. It is responsible for pumping refrigerant throughout the system. The compressor compresses the refrigerant, raising its temperature and pressure, and pushes it into the condenser coil. As the refrigerant flows through the condenser coil, it loses heat to the outside air and cools down. The refrigerant then moves to the evaporator coil, where it absorbs heat from the indoor air, thereby cooling the room. The refrigerant, now warmed, returns to the compressor, and the cycle repeats.


Types of Compressors

There are primarily two types of compressors used in ductless mini split systems: rotary and inverter. The type of compressor your system uses can impact its efficiency, noise level, and longevity.

Rotary compressors are common in smaller systems. They operate at a fixed speed, meaning they are either on or off. While these compressors are generally less expensive, they can lead to higher energy costs due to their constant cycling on and off. Inverter compressors, on the other hand, can vary their speed based on the cooling demand. This ability to adjust speed makes inverter compressors more energy-efficient and quieter than their rotary counterparts. However, they are typically more expensive.

Installing the Compressor

Installing the Compressor

The installation of the compressor is a critical step in setting up a ductless mini split system. It requires careful planning and precision to ensure the system operates efficiently and safely. While the exact steps can vary based on the specific model of your system, the general process involves mounting the outdoor unit, connecting the refrigerant lines, and wiring the system. It's important to note that this process should be carried out by a professional HVAC technician to ensure proper installation and adherence to safety standards.


Mounting the Outdoor Unit

The outdoor unit, which houses the compressor, should be mounted on a flat, stable surface. This can be either a concrete slab on the ground or a bracket on the wall. The location should be easily accessible for maintenance and far enough from windows and doors to minimize noise intrusion. Once the mounting location is determined, the outdoor unit can be securely fastened to its base. It's important to ensure the unit is level to prevent vibration and potential damage to the compressor.


Connecting the Refrigerant Lines

The refrigerant lines connect the outdoor unit to the indoor units. These lines carry the refrigerant between the compressor and the indoor units, allowing the system to cool your home. When connecting the refrigerant lines, it's crucial to ensure a tight seal to prevent refrigerant leaks. This process typically involves flaring the ends of the copper lines, connecting them to the appropriate ports on the indoor and outdoor units, and tightening the connections with a wrench.


Wiring the System

Wiring the system involves connecting the outdoor unit to a power source and linking it to the indoor units. This process requires a thorough understanding of electrical systems and should be performed by a licensed electrician. The outdoor unit requires a dedicated circuit to handle the power demands of the compressor. The indoor units are typically powered through the outdoor unit, requiring a multi-conductor cable to connect them. Once the wiring is complete, the system can be powered on and tested for proper operation.

Maintaining the Compressor


Regular maintenance of the compressor is essential to ensure the efficient operation of your ductless mini split system. This includes cleaning the compressor, checking for refrigerant leaks, and ensuring the system is properly lubricated. Cleaning the compressor involves removing any dirt or debris that may have accumulated on the unit. This can be done using a soft brush and a mild detergent. It's also important to check for refrigerant leaks regularly, as these can significantly impact the system's efficiency. If a leak is detected, it should be repaired by a professional HVAC technician. Finally, the system should be properly lubricated to ensure smooth operation. This typically involves applying a small amount of oil to the compressor's moving parts. However, it's important to consult your system's manual for specific lubrication instructions.



The compressor is a key component of a ductless mini split system, playing a crucial role in the cooling process. Understanding its function and the steps involved in its installation can help ensure the efficient operation of your system. While the installation of the compressor should be carried out by a professional, having a basic understanding of the process can help you make informed decisions about your system. Regular maintenance of the compressor can also help prolong the life of your system and ensure its efficient operation.


Ready to ensure your ductless mini split system operates at peak efficiency with a trusted partner by your side? At Richair Comfort, we bring our dedication to quality and exceptional customer service to every installation and maintenance service we provide. Since 1994, we've been helping customers like you embrace the benefits of the latest, most efficient ductless technology. πŸ›  Interested in Reliable Maintenance? Schedule your service with us today and experience the RIchair Comfort difference!

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