Residential Multi-Function Heat Pumps: Product Search

Residential heat pump space conditioning and water heating can greatly reduce energy consumption compared to typical natural gas combustion or electric resistance equipment. Multi-function heat pumps are a product type that uses one efficient outdoor compressor and heat exchanger unit to provide both space conditioning and water heating. Multi-function heat pumps have the potential to increase efficiency and reduce cost compared to typical separate heat pumps for space conditioning and water heating by reducing the number of compressors, by recovering waste heat from space cooling to heat water, and by eliminating the need for electric resistance backup or defrost heaters. For residential heat pump retrofits, buildings often need electrical service panel upgrades that add cost and delays. Multifunction heat pumps do not need electric resistance backup or strip heaters so they can avoid the need for electrical service panel upgrades in many buildings, reducing costs for most buildings and particularly for older buildings common in California and particularly common in DAC and HTR areas.   Multi-function heat pump products are currently available as custom designs using air-to-water heat pumps with cooling and heating energy carried into the building by water-glycol mixtures, but their adoption is limited by high costs. The UC Davis Western Cooling Efficiency Center (WCEC) has a PG&E funded emerging technologies project testing a lower cost and potentially higher efficiency air-to-air multi-function heat pump prototype that uses refrigerant to carry cooling and heating energy into the building. Preliminary results show that the prototype has good energy efficiency performance and that it can use waste heat from space cooling to heat hot water.   This proposed technical market characterization project will complete a product search from the largest HVAC and hot water heating equipment manufacturers to identify what residential air-to-air multi-function heat pump products are commercially available or soon to be commercially available in California. This project will be a combination of primary research surveying manufacturers as well as secondary research through literature searches. This project will produce a list of available products and specifications including rated efficiency energy savings estimates compared to mixed fuel and all electric baselines. This product search will inform future projects to improve equipment design, validate energy efficiency through laboratory and field demonstrations, and determine costs for equipment and installation.