DUCTLESS HVAC-Not Your Grandfather’s HVAC System

by D. Brent Sauser, AIA
July 15, 2021

When you step into your home at night do you switch on all your lights?  Of course not.  Yet, that is precisely what we do with the most expensive system in the house . . . our HVAC system.  When the HVAC comes on, it comes on everywhere in the house, including all the unoccupied rooms.  Does that make sense to you?  Regardless, that is the traditional way homes in the USA are equipped . . . Central heating and cooling with plenty of leaky ductwork!  Considering the cost of energy these days, you would think there must be a less expensive and more efficient and effective way to heat and cool our homes.

The good news is there is a more efficient and effective way to provide HVAC for less cost and with no sacrifice to comfort.  This is tried and true technology from years of use in Europe and Asia.  The technical term for this technology is Variable Refrigerant Flow (VRF) Systems.  It is more commonly known as Ductless HVAC Systems, or ductless, mini-spilt systems.

While conventional HVAC systems heat and cool the entire interior space (regardless of whether it is in use or not) via ductwork that could be leaking energy by as much as 20% from the ductwork, ductless systems condition a space without the use of ducts, saving space and allowing the unit to be retrofitted into spaces without ducts.  Ductless mini-split systems can be designed to cool several rooms, much like what we have come to expect from a conventional central air system.  Ductless systems offer individual temperature control and allows for the option to condition occupied spaces through zoning controls.  Energy is not wasted in areas that are unoccupied and no loss of efficiency occurs because there is no ductwork.   Efficiency levels well above SEER 25 can be expected with a ductless installation.  That translates to money back in your pocket!