Ductless mini-split air conditioners and heat pumps offer energy-efficient, convenient alternatives to ducted heating, ventilation and air conditioning systems. As the name implies, ductless systems do not require ducts to distribute conditioned air. Instead, individual blower cassettes installed indoors link to an outdoor compressor by a conduit that carries refrigerant, power and condensate lines. Individual controls offer precise temperature regulation, and each blower can be shut off when not in use.

Instead of cooling an entire home, mini-splits cool single rooms or zones. They are a good choice for add-ons, older homes where installing ducts is not feasible and rooms that are hard to connect to an existing ducted system. They work well in apartments or new homes that do not require large HVAC systems.

Mini-Split Ductless Systems Defined

Ductless systems operate on the same principles as ducted systems. Just like a standard air conditioner, refrigerant is routed through the compressor and condenser to the evaporator coil, which blows conditioned air into the living space. However, instead of conditioned air passing through ducts that blow air into all the rooms of a building, ductless systems cool individual rooms or zones. They are available as air conditioners only or as heat pumps that heat and cool.

An outdoor compressor connects to one or more indoor air handlers. Depending on the brand and model, up to eight blower units can be connected to a single compressor. The compressor can be installed in a convenient location outdoors. The small size of the compressor cabinet makes it easy to install on an exterior wall, rooftop or slab on the ground. It should be level and placed for easy access for servicing. Unlike traditional air conditioning compressors, mini-splits do not make much noise, which makes them convenient to install near a window or door.

Indoor units come in several configurations, including wall-mounted, ceiling cassettes and floor-mounted units. Wall-mounted blowers should be located at least six feet above the floor. Ideally, the indoor cassette should be mounted on an exterior wall to shorten the distance between the blower and compressor and accommodate the condensate drain, which releases moisture to the outside.

To install the system, a small hole approximately 3 inches in diameter is drilled through the wall for the conduit. The outdoor unit can be placed up to 50 feet away from the indoor unit. Some models allow longer extensions between the indoor and outdoor components. However, as distance increases, efficiency decreases.

Each blower has its own remote control that allows adjustment of temperature, fan speed and louver orientation. Individual controls let you set the temperature and fan speed for each room, such as keeping a bedroom warmer than the living room. Unlike central ducted systems that deliver air to each connected room, individual blowers can be turned off when not in use, which saves energy and lowers utility bills.

Mini-Split Heat Pumps

Heat pumps work on the same principles of refrigeration as traditional HVAC systems. The difference is that heat pumps use energy to move heat from one place to another instead of using energy to heat and cool.

As refrigerant cycles through the system, it is compressed, which creates a hot gas. When the pressure is released, the refrigerant cools and absorbs heat. In the summer, refrigerant extracts warm indoor air and transfers it outside. In the winter, refrigerant absorbs latent heat from the outdoor air and brings it inside. In heating mode, heat pumps produce approximately three to five kilowatts of thermal energy for every kilowatt of electricity consumed, making them extremely energy-efficient. A reversing valve changes the flow of refrigerant.

Advantages of Ductless Systems

There are many advantages to ductless mini-split systems. Their compact size makes them easy to install in small spaces. Installation is usually completed in one day with minimal disruption to a household.

They can be used as the primary source of heating and cooling or as an auxiliary source to even out temperatures and increase comfort in rooms connected to a ducted system. If your home does not have a ducted HVAC system, mini-splits solve the problem. Use them for room additions, attic conversions, garages, outbuildings or basements.

Ductless systems are more energy-efficient because there is no energy loss through ducts. According to the Department of Energy, ducts that run through unconditioned spaces can lose up to 30% of the conditioned air flowing through them.

Because there is no air exchange between rooms, pollutants are not distributed throughout the living space. Instead, each blower has its own filter, which should be cleaned every month. Mini-split heat pumps are powered by electricity instead of fossil fuels. Oil and gas heating equipment creates toxic gases, which can be hazardous in high concentrations.

The sleek, modern look of the indoor cassettes protrude from the wall approximately seven inches. They are available in a range of colors and designs, making them easy to integrate into your d├ęcor. The indoor units are quiet, simply blowing conditioned air into the living space.

New technology offers energy-saving features, including variable speed inverter compressors and fans that allow equipment to constantly respond to temperature changes. Single-speed compressors run at only one speed, cycling on when thermostats alert the system to run and shutting off when the set temperature is reached.

In contrast, variable speed inverter compressors modulate the power supply. By operating at 150 different speeds, they can run efficiently in a wide range of temperatures. Variable-speed electronically commutated motor fans, called ECMs, increase efficiency and comfort. Some mini-split models include expansion valves with up to 400 different positions to better modulate the flow and compression of refrigerant.

Variable speed inverter equipment improves indoor comfort. Traditional air conditioners shut off when reaching the set temperature. In contrast, mini-split air conditioners run longer at lower speeds for consistent temperature and humidity control. During most of the day, when less cooling or heating is needed, they run at lower speeds, using less energy to deliver conditioned air. During the hottest times of day, they run at higher speeds to maintain comfort.

Hire an Experienced Professional for Ductless Installation

If you are considering a mini-split for your San Marcos, California, home or office, hire a contractor with experience in installing and servicing this technology.Oak Island Heating and Air Conditioning has served area residents since 1998. As a Lennox Premier Dealer, we consistently provide exceptional customer service and technological expertise.

Our technicians have experience in installing and maintaining ductless systems, including heat pumps and air conditioners. We use industry standards to calculate load, an important factor in long-term performance.

We offer some of the best products on the market, known for their efficiency and durability. Our service technicians are certified by NATE, the industry leader in technician certification.

Our services include:

  • Air conditioning, heat pump and furnace installations
  • Preventive maintenance on all HVAC equipment
  • Heating and air conditioning repairs
  • Indoor air quality services and air purification equipment
  • Humidity control systems
  • Ventilation systems
  • Ductless mini-split installations, repairs and maintenance

Call Oak Island Heating and Air Conditioning today to talk to our technicians about how ductless systems can increase comfort and save money on utility bills in your San Marcos, California, home or office.

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