idronics #27:  Air-to-Water Heat Pumps
New release: Hydraulics N. 27

Air-to-Water Heat Pump Systems

idronics #27:  Air-to-Water Heat Pumps

Air-to-Water Heat Pumps (#27, July 2020)

There are many types of heat pumps. The one most of us are familiar with is our kitchen refrigerator. It removes heat from food and pumps it back to the kitchen.

Over the past three decades refrigerator manufacturers have continually introduced new ways to reduce the energy used by their products. No longer is a homeowner’s decision to replace their refrigerator based mostly on its age. Now, the electrical energy savings offered by the latest technology can justify the purchase - even though their current refrigerator is still functioning.

The design of heat pumps that supply space conditioning and domestic water heating has also improved dramatically. Enhanced vapor injection, variable speed inverter compressors, electronic expansion valves and other state-of-the-art technologies have been integrated into many modern heat pumps . The resulting efficiency gains now allow air-source heat pumps to be used in cold Northern climates, even when outside temperatures fall below 0ºF. And because they operate on electricity, rather than fossil fuel, they are well-positioned for today’s focus on carbon reduction driven by changing social attitudes and government policies. 

This issue of idronics deals with “air-to-water” heat pumps that heat buildings by absorbing low temperature heat from outside air and delivering it, at higher temperatures, to a hydronic distribution system.  These heat pumps combine the advantages of modern air-source heat pump technology with the unsurpassed comfort of hydronic heating and cooling. They are widely used in Europe and Asia, and represent a growing market opportunity within North America.

We trust you will enjoy this issue of idronics and encourage you to send us any feedback by e-mailing us at

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