A ductless line set connects the outdoor condenser and the indoor air handler. They are essential to the heating and cooling process of mini-splits since they transport refrigerant in and out of the indoor and outdoor units. Therefore, you should select a ductless installation company that selects and installs line sets properly. Otherwise, your mini-split will not function as necessary.
In this article, we will help you learn everything you need to know about ductless line sets for your mini-split system.
What Is A Line Set?
- 1 What Is A Line Set?
- 2 Single-Zone And Multi-Zone Ductless Configurations
- 3 Line Set Accessories
- 4 Line Set Sizing
- 5 Incorrectly Sized Line Sets
- 6 Call PFO Heating & Air Conditioning To Learn More About Ductless HVAC Systems
A line set is made of two copper tubes that connect the condenser to an indoor air handler. The copper tubes come in two different sizes, with one line larger than the other. The smaller tube is called the liquid or discharge line. This line is responsible for moving the dense liquid refrigerant to the indoor unit where it absorbs heat. Secondly, the larger tube is referred to as the suction line. It carries the gaseous refrigerant to the condenser where the heat is released.
The liquid and gaseous refrigerant continuously circulate between both lines to provide you with conditioned air. The flow is reversed when you need heat, depending on if you need heating or cooling.
Single-Zone And Multi-Zone Ductless Configurations
If your house has a single-zone unit, it’s only necessary to buy a single line set. But, if you have a multi-zone system, then you will have to purchase one line set per indoor unit. You also have to take a few things into consideration, such as the total line length, distance, and diameter of each set. Otherwise, your system may not function properly. A professional HVAC contractor can determine this for you before any installations take place.
Some multi-zone units need a branch box to provide refrigerant from the condenser to the indoor units. Because of this it needs its own line set to connect with the outdoor unit. Branch boxes are manufacturer-specific which means not all branch-box combinations are supported. Therefore, it is essential you choose a trusted HVAC installation company to make sure they select the correct branch box for your unit.
The HVAC contractor may additionally recommend a port adaptor. This helps make a connection if the diameter line is not the standard fitting on your mini-split. Some homeowners think these adapters can restrict the refrigerant flow. There is no need to worry because the adapters are designed to allow the proper flow of refrigerant. By using a port adapter, the HVAC contractor won’t have to modify the current line you have. These adapters allow an HVAC contractor to use the correctly-sized line without having to worry about the fitting size.
It’s important to remember that the ductless installation company you choose should follow the manufacturer’s recommendations strictly when it comes to the sizing of refrigerant piping connections. Installing a ductless mini-split system is not something you should do yourself. It requires the knowledge and expertise of a licensed HVAC contractor.
Line Set Accessories
Using a few line set accessories will to help make your mini-split experience easier:
The Rectorseal NoKink has a flexible connection between the refrigerant line and the mini-split evaporator. It’s easy to install due to its NoKink technology and three-inch copper stub. It will prevent the refrigerant line from kinking which saves time and labor costs. Also, it helps ensure that your unit is running at its optimal efficiency.
Another helpful accessory is a ball valve. It is designed to easily suspend refrigerant flow without needing to remove the seal cap. It makes servicing the refrigerant lines fast and simple. This accessory also has a Schrader valve for fast charging. A ball valve is necessary for multi-zone systems because it allows the system to be serviced without needing to remove the refrigerant out of the lines.
Line Set Covers
A line set cover hides and protects the copper line set of your mini-split. Without this accessory, your line set is exposed to natural elements like direct sunlight and rain. UV rays can accelerate the deterioration of your line sets. Therefore, a line set cover protects against these elements and any weather conditions.
A great perk of a line set cover is that it is completely paintable. So, you can match its color to your wall or paint it in any design you want. This is an excellent way to blend your line set cover into your home’s aesthetic.
Line Set Sizing
Line sets come in multiple sizes. The sizing is determined by factors such as the number of evaporators, the mini-split make and model, the distance between units, and the condenser size. The size of the line set is predetermined by the manufacturer. To make sure you get the exact sizing requirements needed for the mini-split you purchased, choose a ductless installation company with a lot of experience.
The size of the line set is determined by the size of your mini-split. The higher the British thermal unit (BTU) or tonnage, the larger the diameter line set needs. Mini-splits sizes are indicated by numbers. The first number indicates the diameter of the liquid line, and the second number is the diameter of the suction line. For example, a large line set has a 3/8″ liquid line and a 3/4″ suction line. A smaller line set has a 1/4″ liquid line and a 1/2″ suction line.
The maximum line set length needed by your mini-split is called the distance. It’s important for the HVAC contractor to determine the length because it impacts where your outdoor and indoor units will be located. When they measure the distance, make sure they consider the corners and bends in your house, and also the wall thickness and the vertical rise to get an accurate measurement.
Choosing an inexperienced ductless installer will inevitably lead to an issue after they have installed your mini-split. Your indoor unit may be placed too far from the outdoor unit. If this happens, your unit will not operate properly because it will exceed the maximum length required.
Something else that affects the refrigerant in the line set is the distance between the outdoor and indoor units. A mini-split is already charged with the required refrigerant when you purchase it. Usually, the factory charge is enough for the majority of installations. But, if your unit needs a longer line set then the HVAC contractor might need to add more refrigerant to make sure your mini-split operates at its maximum capacity. To make sure you have the right amount of coolant for your ductless installation, hire an experienced HVAC contractor.
Ensure your line sets are built to last by checking with your HVAC contractor that they are the highest quality line sets. Also, check to see if the line set underwent annealing. Annealing is a heat-treating process that allows the copper to flex without breaking or kinking. Also ensure your line set has a manufacturer warranty of at least five years.
A high-quality line set also has flared ends. This allows for an easier installation because your HVAC contractor will not have to braze it. Also, it should come equipped with at least half an inch thick insulation. Additionally, make sure the UL is rated for fire and smoke is listed for weather resistance. These qualifications assure that your line set is safe to use.
Incorrectly Sized Line Sets
If your line set is improperly sized, you are bound to encounter some problems. Some of the main issues if the line sets are either too small or too big include:
If the suction line in your line set is too small, it results in not enough operating pressure. In turn, it will hinder your mini-split system’s capacity and efficiency. It can also lead to a shorter system lifespan.
Furthermore, an undersized liquid line means that the indoor and outdoor units won’t receive the proper amount of refrigerant. The unit’s operating pressure will be affected by this as well. This results in your system not correctly functioning to its maximum capacity.
Besides the possibility of the line being undersized, it can also be too big. This means that the refrigerant pressure will be lower than what is needed. The liquid might not be transported back to the compressor as efficiently as well. Consequently, the compressor will not operate correctly because there won’t be enough refrigerant to help the compressor release any built-up heat.
An oversized liquid line can hold a larger amount of refrigerant. But, the liquid will become easily diluted. The compressor can end up damaged due to the shortage of refrigerant.
For your mini-split system to work at its optimal performance and maximum efficiency, it’s essential to have the proper supporting components. Making sure your line set is properly sized and installed is crucial to your unit’s overall functionality. Always work with an HVAC company that correctly follows the manufacturer’s guidelines during installation.
An experienced HVAC contractor can help you buy the right unit and line sets and test the newly installed mini-split. With professional assistance, you will soon have the home comfort you deserve.
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Call PFO Heating & Air Conditioning To Learn More About Ductless HVAC Systems
Interested in learning more about ductless HVAC systems? For all your HVAC system needs, call PFO Heating & Air Conditioning today. Our technicians are all NATE-certified, and they have a great deal of experience. They’ll also determine what your home comfort needs are and find the best and most affordable solutions to meet them.
As a full-service HVAC company, PFO Heating & Air Conditioning offers an array of HVAC services. This includes heating and cooling installations, tuneups, repairs, and much more. We offer free, in-home consultations. Call now to schedule an appointment.