Ductless mini-splits are a unique type of HVAC system that provides efficient and effective air conditioning and potentially also heating. Mini-split systems are more efficient and use much less energy than central HVAC systems. This can make them a good choice when building a new home or for homes that don’t have central heating and air conditioning. There are also situations where combining a mini-split system with an existing central HVAC system is a good choice, and this article will discuss why and explain how mini-split systems work.

How Ductless Mini-Split Systems Work

Ductless mini-split systems can use a traditional AC condenser unit. However, most mini-split systems instead use a heat pump, which allows them to provide heating in addition to air conditioning. The condenser or heat pump sits outside the house and is connected to one or more air handler units inside the house. The air handlers are typically mounted near the top of a wall, but they can also be installed on the floor or in the ceiling.

A mini-split system cools just like a central AC system or heats and cools just like a central heat pump system. This means that it uses refrigerant to remove heat from one location and then transfers and releases the heat in another location. When the system is cooling, cold refrigerant flows through the evaporator coil in the air handler. The fan in the air handler continuously pulls warm air in so that it blows over the evaporator coil. As air moves over the coil, lots of the heat it contains is absorbed by the refrigerant. This process works naturally due to the difference in the temperature of the air and the refrigerant.

The refrigerant is constantly pumped inside the air handler and then back outside to the heat pump or condenser. The cold refrigerant is pumped inside the air handler and removes heat to cool the surrounding area down. The warmer refrigerant then gets pumped back outside and into the compressor. Compressing the refrigerant causes its pressure and temperature to drastically increase. This leads to it boiling and transforming into a superheated gas that’s around 120-140 degrees hot.

Compressing the refrigerant is essential since it makes it hotter than the air temperature outside. As the compressor fan in the outdoor unit blows air over the condenser coil that the hot refrigerant flows through, the heat is instantly released from the refrigerant into the air. Finally, the refrigerant is then pumped through an expansion valve before flowing back inside. This decreases the pressure and makes the refrigerant cold enough that it can then again pull heat out of the home.

When a mini-split heat pump system is heating, this entire process works in reverse. That means cold refrigerant captures heat from outside, and the heated refrigerant flowing through the air handler then releases the heat inside to make the surrounding area much warmer.

Now that you understand how a mini-split system works, let’s look at some of the benefits you can have by combining a mini-split with your existing HVAC system.

Overcome Hot and Cold Spots in Your Home

Central HVAC systems often have issues with heating or cooling every room or part of the home to the same temperature. When functioning correctly, most central HVAC systems will typically run for about 15 minutes at a time and cycle on and off several times per hour. Any parts of a home that have higher ceilings tend to stay warmer in the summer and cooler in the winter. Areas with lots of windows or skylights gain lots of heat from the sun as well, which also makes them hotter in the summer. If the windows aren’t fully sealed or not well insulated, they can also allow lots of cool air in during the winter.

All these issues can easily lead to hot or cold spots in different parts of the home since a central HVAC system typically won’t ever run long enough to overcome them and fully heat or cool certain areas. Unfortunately, there isn’t much you can do to help your central HVAC system eliminate these hot and cold spots since it will run only until the central area, where the thermostat is located, reaches the selected temperature.

If you have any rooms that are always hotter than you want in summer or colder in winter, installing a mini-split system is a great option that will eliminate the problem. In a mini-split system, you can program each air handler unit to your desired temperature. The system will then continue running until it reaches the correct temperature and eliminate the hot or cold spots.

Supplement Your Heating and/or Cooling Needs

Many families end up arguing over the thermostat since some people may prefer warmer temperatures, and others are more comfortable when it’s colder. If you prefer your bedroom to be much cooler in the summer or warmer in the winter, installing a mini-split in your bedroom is also a great option. With a mini-split, you can leave your central HVAC system at one temperature while also heating or cooling your bedroom to whatever temperature makes you the most comfortable.

This setup can also help you save money on your energy bills. Turning your central heating or AC down at night will make it run less often and use less energy. You can then just use the mini-split to keep your bedroom as warm or cool as you want.

Cost-Effective Heating and Cooling for Your New Addition

If you’re planning on putting a new addition onto your home, heating and cooling the addition with a mini-split system will almost always be the most cost-effective option. Unless you’re only putting a tiny addition onto your home, you will almost always need to replace your existing heating and cooling units. If you don’t upgrade to larger, more powerful heating and cooling units, your HVAC system will very likely end up struggling to keep your home as comfortable and warm or cool as you want. Installing a mini-split system to heat and cool the addition will cost you much less than replacing your existing AC and furnace or central heat pump.

When adding onto your home, you will also often have to replace some or all of your existing ductwork. If not, your ducts will likely end up being too small and not provide sufficient airflow for your HVAC system to work effectively. The size of your air ducts determines the volume of air that your HVAC system can circulate. When you increase the size of your home, the amount of air that your HVAC system needs to circulate to work effectively also has to increase.

Replacing your ductwork will usually cost at least a few thousand dollars, but you can avoid this extra cost by instead installing a mini-split system in the addition. The fact that mini-splits are more energy efficient than central HVAC systems also means that you’ll pay less to heat and cool your new addition.

As the most trusted heating, air conditioning and plumbing service in Gilbert and the Phoenix area, A/C Doctors is the company to trust for mini-split installation. We carry a wide range of different mini-split systems and can help you choose the best option for your home. We also install, repair and service all types of central HVAC systems. For more information on the ways a mini-split system can benefit your home or to schedule an installation consultation, contact us today.

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