Little, Ductless, Different: Mini-Split Heat Pumps

Gita Subramony for Zondits, April 18, 2014

Ductless mini-split heat pumps (DHPs) offer efficient heating and cooling solutions for a range of residential and small commercial spaces. Recent developments offer improved cold weather performance, with many models providing heat when outdoor temperatures drop well below zero. The systems consist of an outdoor compressor/condenser unit and one or more indoor air-handling units. They are particularly good for residential retrofits where the existing system does not contain ducts, or in other situations where adding ductwork is not practical. These units have been in common usage in Asia and Europe for decades and they are becoming more commonplace in the USA.

In addition to offering flexible heating and cooling options, the DHPs have the potential to offer substantial energy savings for the end user compared with electric heat, oil heat, and standard AC and heat pumps. Some utilities offer rebate programs to help customers offset the cost of the equipment. However, given their freshness to the US market, there are a number of questions that surround the performance of these units. Northeast Energy Efficiency Partnerships (NEEP) is actively researching DHPs as part of their Emerging Technology program. They have published a Market Strategies Report, performed by Stephen Winter Associates, which provides an overview of DHP market potential. NEEP is now in the final stages of publishing the results of three-season performance monitoring which was conducted by ERS, a consulting engineering firm specializing in energy efficiency. Zondits will post more details on ERS’s methodology and findings once the report is available.