SUWANEE, Ga. — Mitsubishi Electric Trane HVAC US (METUS), a supplier of energy-efficient, high-performance ductless and ducted variable-capacity heat pump systems and variable refrigerant flow (VRF) heat pump and air conditioning systems, announces Heat₂O^™️, an all-electric domestic hot water heating system designed to improve sustainability and reduce energy consumption in multifamily buildings and large-scale commercial facilities.

Domestic hot water (DHW) accounts for roughly 25% of annual energy usage in typical multifamily buildings^[1] and is among the largest single energy uses of energy for new multifamily construction in the Northwest.^[2] The Heat₂O heat pump water heater (QAHV-N136TAU-HPB(-BS)) reduces the environmental impact of DHW through energy-efficient operation while using CO₂, a natural and environmentally friendly refrigerant with a global warming potential (GWP) of 1 and an ozone depletion potential (ODP) of zero. Able to produce high-volume DHW without fossil fuels, Heat₂O can help multifamily buildings, offices, hotels, gyms, educational institutions, and other large-scale and commercial facilities qualify for sustainability certifications or achieve zero-energy and passive house status. 

Engineered Solution

METUS provides Heat₂O as an engineered solution with comprehensive technical support. The system includes pre-assembled and pre-plumbed components designed and selected to ensure installation quality and ensure optimal performance of the heat pump. Components include hot water storage tanks, swing tanks, secondary heat exchangers, and variable-speed secondary circuit pumps.

Heat₂O transfers ambient thermal energy from outdoor air to potable water by cycling refrigerant. Natural CO₂ refrigerant enables Heat₂O to supply hot water up to 176° F even in low ambient conditions without burning fossil fuels. 

Using Mitsubishi Electric’s patented Twisted Spiral Gas Cooler, the system achieves highly efficient heat exchange with three refrigerant lines wrapped around a twisted water pipe.

The CO₂ refrigerant flows in the opposite direction of the water. Running the refrigerant lines along the pipe’s grooves increases the heat conductive area while the spiral helps create a vortex in the pipe, accelerating the turbulence effect of water and reducing pressure loss in the heat exchanger. Additionally, the copper pipes make for double-walled construction. 

An INVERTER-driven scroll compressor increases Heat₂O’s energy efficiency by enabling the system to modulate refrigerant flow and heating capacity to match loads. 

“For more than 30 years, Mitsubishi Electric has been a leader in heat pumps for space conditioning,” said Cain White, director, commercial product management, Mitsubishi Electric Trane HVAC US. “By applying our variable-speed, INVERTER-driven technology to water heating with Heat₂O, we’re giving building owners far greater control over energy consumption and sustainability than is possible with fixed-capacity hot water heat pumps.” 

Savings

Heat₂O can provide over four times more energy as heat than the system consumes in electricity. With a coefficient of performance of up to 4.52, Heat₂O offers significant energy savings for building owners and tenants. Energy savings combined with incentives from utilities can ultimately offset first costs. 

Cold-Climate Performance and Scalability

Heat₂O can operate at high capacity even in cold climates such as climate zones 5 and 6. The system delivers 100% heating capacity of 40 kW at ambient temperatures as low as 36°F. When down to minus 13° outside, the system can still supply 176° hot water but at 50% of the heating capacity. 

In extreme cold, Heat₂O’s compressor uses flash-injection technology to operate at high speed, maintaining high discharge pressure and ensuring the compressor shell is kept cool at all times to capture ambient heat. 

Heat₂O heat pump water heater is capable of operating at three capacities: 136,485 Btu/h (40 kW), 170,607 Btu/h (50 kW), and 204,728 Btu/h (60 kW). Up to six units can be piped in parallel for a maximum size of 682,425 Btu/h (240 kW). Plans are in the works to expand the allowance of up to 16 units in the future and for a capacity of 2,183,760 Btu/h (640 kW). 

METUS is introducing Heat₂O in New York, Massachusetts, Washington, Oregon, and northern California, with other regions to follow. For more information, visit MitsubishiComfort.com or Heat2O.com. 

[1] U.S. Energy Informational Administration 

[2] Bonneville Power Administration