The Technology Behind and Benefits of Air-to-Water Heat Pumps
Have you noticed an increasing demand from customers for efficient HVAC systems? With growing environmental concerns and the push for sustainable solutions, more people are seeking eco-friendly alternatives to heat and cool their homes than ever before. In addition to unprecedented federal and state regulatory changes to increase the use of residential heat pumps in the U.S., there are several homeowner incentives such as the Inflation Reduction Act and utility rebates which make the efficient and sustainable technology even more affordable.
With these industry shifts, residential air-to-water heat pumps have emerged as a transformative solution to lower carbon emissions, enhance energy efficiency and reduce utility bills. Although they have been used throughout Europe for decades, they have not yet been widely available in the North American market, but that is starting to change — and for good reason.
Read on to learn more from Bahadir Taşkonak, the North America regional product manager at Johnson Controls-Hitachi, about the technology behind air-to-water heat pumps and the benefits they offer contractors and homeowners.
How has the air-to-water heat pump market developed?
Taskonak: The technology for air-to-water heat pumps was formulated after World War II, and they’ve been used throughout Europe for decades, where their market has grown dramatically in the last 20 years. The North American market for air-to-water heat pumps, on the other hand, is in the early stages, with many predicting dramatic growth in coming years. One reason for the projected growth is due to changes in federal and state mandates and regulations regarding low global warming potential (GWP) refrigerants.
Outdoor refrigerant circuits enable air-to-water heat pumps to remain compatible with refrigerant regulations as GWP requirements evolve. This forward-thinking achievement comes without sacrificing comfort, as many systems reach high heating capacities with low ambient temperatures.
How does an air-to-water heat pump achieve enhanced efficiency and sustainability?
Taskonak: Air-to-water heat pumps are highly efficient because of their refrigerant cycle. They use high-efficiency vapor injection compressor technology that mimics the operation of a natural gas boiler for heating operations. Instead of consuming fuel, air-to-water heat pumps pull energy from ambient air and transfer it to a closed water loop located inside a living space.
More recent innovations have taken the technology even further, enabling advanced air-to-water heat pumps to achieve and maintain high heating capacities even within low ambient conditions. For example, the airH2O Yutaki M Air-to-Water Heat Pump by Hitachi utilizes an enhanced vapor injection twin-rotary compressor design that enables a sustainable compression ratio even at low ambient temperatures to generate more stable heating capacities during cold winter days.
As a result, the Yutaki heat pump can achieve indoor heating temperatures as high as 140° F, and the system can operate down to -13° F. Within most applications, this means a backup heat source is not required. Additionally, a built-in smart defrost timing system rapidly de-ices and auto-dries coils to ensure more consistent, high-capacity heating without interruption while enhancing energy efficiency.
What are the other benefits of an air-to-water heat pump?
Taskonak: Air-to-water heat pumps are a year-round plug-and-play solution. Besides being able to heat and cool spaces efficiently even in cold climates, the systems can be configured to be customized based on customer needs. For example, the Yutaki system has a highly flexible terminal board that features 40 connections, so it can also be used to heat a home’s swimming pool and provide domestic hot water.
Further, the closed-loop, monobloc design of air-to-water heat pumps enables the systems to operate with low-GWP refrigerants such as R-32. The sealed outdoor piping also means the systems are compatible with possible future refrigerant options, including R-290 (propane), making it a safer and environmentally forward option now and in the future, which is an important benefit to contractors and homeowners.
What’s the installation process like for air-to-water heat pumps?
Taskonak: Air-to-water heat pumps are relatively easy to install. Since they have a sealed refrigerant loop, the full refrigerant circuit remains outside the home, within factory-sealed piping. Therefore, most of the installation work takes place outside, and a refrigerant leak detection system is not required, further simplifying installation.
The system includes two primary elements. The outdoor unit is a monobloc design with all system components maintained in a single entity. After the outdoor unit absorbs outside air, it passes the air to the condenser. The air is then sent through the piping. Therefore, no site excavation is necessary. These two factors usually mean simpler and quicker installs than for other HVAC systems.
And because the refrigerant loop is sealed, no refrigerant handling is required to further streamline the process. The ease of installation makes the system an ideal solution for contractors tasked with providing more reliable and efficient home comfort while meeting stringent sustainability regulations.
What would you say to a contractor considering offering this type of technology?
Taskonak: As the residential HVAC landscape continues to evolve, systems designed to adapt to these shifting requirements are more important than ever before. Air-to-water heat pumps provide an easy-to-install solution that meets current environmental regulations while prioritizing the safety of homeowners and contractors. Forward-thinking outdoor refrigerant circuits enable air-to-water heat pumps to remain compatible with refrigerant regulations as GWP requirements evolve. Combined with their cold-climate performance, air-to-water heat pumps are an ideal solution for contractors tasked with providing more reliable and efficient home comfort while meeting stringent regulations.