A Ductless Split System May Be Just What Your Home Needs
Even though ductless split systems have become more popular across the country over the past decade, many homeowners remain unclear on how they work. Here are the answers to some frequently asked questions about high-efficiency ductless heat pumps and cooling systems.
Ductless Split System FAQs
Of course, we’ll start with the basics…
What is a ductless split system? Also called a ductless mini-split, a ductless split system is most often a split-system air-source heat pump with one main difference from regular air-source systems – they work without ductwork (hence the name). A conduit containing lines for refrigerant, electricity and condensate connects a single outdoor compressor unit with one or more indoor air-handling units. Each air-handling unit contains a coil and a fan, providing independently controlled heating or cooling to the room or small area where it’s installed. (Some ductless systems provide only cooling.)
How does the ductless system work? These units work much like traditional air-source heat pumps, using a chemical compound (called refrigerant or coolant) to transfer heat energy between inside and outside. In heating mode, the ductless split system removes heat energy from the outside air, and brings it inside, where it’s released from the coil in the air-handling unit. This warms the air, which the unit’s fan distributes into the room. In the summer, the ductless system works like an AC, extracting heat from the room or area where the air-handler is installed and releasing it from the coil in the outside compressor unit. With no ductwork needed, these systems experience much less energy loss than traditional forced-air heating and cooling systems.
Do ductless split systems operate at one level? Most modern ductless systems employ variable- or multi-speed compressors, using inverter technology to adjust their output to the room’s heating or cooling needs at any given time. This improves comfort while saving energy, and avoids the noisy on-and-off cycling common in many heat pump, AC and furnace systems.
How do you operate a ductless split system? Ductless mini-splits typically come with independent temperature control in each area where an air-handling unit is installed. Most ductless systems can use one compressor unit to serve several air-handling units, each equipped with a remote control. The remote controls often have programming capability.
What situations are best suited for ductless split system? If you are adding a room or section onto your house, or renovating a porch or garage into a bedroom or family room, a ductless system can be a practical and efficient alternative for heating and cooling that space. Installing one of these systems means you won’t have to pay to extend the ductwork in your home, which in any event likely risks over-extending the home’s central heating and cooling system. In homes without ductwork, a ductless split system can be a safe and efficient replacement for baseboard heating or combustion space-heating. Some homeowners use ductless mini-splits for parts of the home that are particularly hard to heat or cool. They’ve also been used in situations where homeowners’ associations don’t allow window air conditioners.
Are ductless split systems more efficient than other systems? Like other well-maintained heat pump systems, ductless systems are able to convert one unit of electricity into three of four units of heat output. This compares favorably with a combustion furnace, which no matter how advanced the technology, can’t convert more than 99 percent of its fuel into heat. For cooling, ductless split systems employ cutting-edge technology to provide high-efficiency air conditioning. The particular efficiency of these systems results from three main factors: 1) independent temperature control so heating or cooling can be easily shut off to unused rooms or areas; 2) inverter technology that gradually adjusts output to match needs; and 3) elimination of ducts with their air leakage and heat loss.