What are Mini Split Line Sets?

15 Foot 1/4 LL 3/8 SL Ductless Mini-Split Line Set

If you are familiar with ductless mini split systems, you know that these innovative heating and cooling units are composed of two main components: the outdoor unit and the indoor unit (or multiple indoor units.)

Mini split line sets are essential for proper system functioning since they are responsible for transporting the refrigerant between the outdoor unit and the indoor unit(s).

What are the Components of a Mini Split Line Set?

Think of a mini split line set as the arteries of a mini split system.  

Just like our arteries connect various vital organs in our body to help us function properly, the line sets in a mini split system do the same thing for the outdoor and indoor unit(s).

The mini split line set consists of two copper pipes that are semi-flexible and work to transport refrigerant throughout your heating and cooling system.

Since the proper circulation of refrigerant is the whole reason your mini split system is able to heat and cool your home or office, the line set’s job is clearly a vital one for your mini split to work as you intend it to.

A line set consists of two copper tubes which each have an important function:

1. The Suction line --

This is the larger diameter tube that connects the evaporator outlet to the compressor inlet. This line is responsible for transporting the refrigerant when it's in its gaseous state.

2. The Liquid line --

This is the smaller diameter tube that connects the condenser to the expansion valve. This line is responsible for transporting the refrigerant once it's in its liquid state.

Copper line sets are available in a variety of sizes and lengths but will always feature insulation on the outside of the line. The lines will possess flare fittings at each end line to ensure a tight, pressure-resistant seal.

Why Size Matters

In order for copper line sets to be able to do their job correctly, it's important to make sure the right-sized copper line set is purchased and installed. 

Let's look at the reasons why:

Refrigerant Flow and Efficiency:

The size of the copper line set directly impacts the flow of refrigerant between the indoor and outdoor units. 

 If the line set is too small, it can lead to increased pressure drop and reduced refrigerant flow. If a line set diameter is too large, it will contain a higher volume of refrigerant in the system than the system design permits. In either case, there can be negative consequences for the performance, efficiency, and longevity of the mini split system.

Optimal Performance:

Mini split systems are designed to operate within specific performance parameters. When the line set is appropriately sized, the system will achieve its intended operating conditions, including temperature differentials, humidity control, and energy efficiency.

Avoiding System Damage:

An incorrectly sized line set can lead to problems such as refrigerant flooding or inadequate refrigerant return, which can damage the compressor, leading to costly repairs and reducing the overall lifespan of the system.

Warranty Considerations:

Many manufacturers specify the exact required line set size for their mini-split systems. Installing an improperly sized line set size could potentially mean that the manufacturer's warranty will no longer cover any repairs or replacements.

Avoiding Leaks:

Inadequate refrigerant flow resulting from an undersized line set can cause refrigerant to linger in certain parts of the system, increasing the risk of hazardous refrigerant leaks, which are environmentally harmful, time-consuming to repair, and lead to system malfunctions.

It's important to follow all manufacturer recommendations and guidelines to ensure the correct sizing of the copper line set required for your mini split system. A reputable mini split manufacturer will always be able to help you find the right equipment and accessories for your mini split system and take all the worry and hassle out of your final decision.

Factors to Consider in Line Set Selection

Though the size of your copper line set will be very important for your mini split system's performance, you'll also want to think about the length of the product as well.

Copper line sets come in a variety of lengths, from 15 feet to 65 feet or more. 

How do you know what length is going to be best for your home or office? When planning and calculating the mini split installation cost, you should think about factors such as how many indoor units you want to install, the distance from each indoor unit to the outdoor unit, and whether you have significant elevation changes around your home or building to consider.

This is yet another critical instance when choosing a reputable mini split manufacturer makes a huge difference in the installation success of your system.

Make sure you research, read reviews and select the best HVAC company you can find before you invest in both your new ductless mini split system as well as all the required equipment and accessories that enable the system to operate as designed.

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Why Alpine Home Air Products is the Industry Leader in Mini Split Systems and Line Sets

When it comes to HVAC systems, supplies, and accessories, Alpine Home Air Products Air is the industry leader in high-quality products for every type of heating and cooling need.

For over 20 years, the Alpine name has been synonymous with reliability and innovation when it comes to all things HVAC-related.

Our commitment to customer satisfaction is reflected in our extensive range of heating and cooling components, including mini split outdoor units, indoor units, line sets, and accessories.

Ready to start shopping? Come take a look at everything we have to offer, or reach out to one of our many experts for help in making your final decisions.

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