Hitachi launches CO2 heat pump water heaters with solar-friendly tariff controls
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Hitachi Global Life Solutions, a unit of Japanese technology conglomerate Hitachi , has announced a new series of residential EcoCute heat pump water heaters for the Japanese market, with sales set to begin progressively in November 2026.
The new Y series uses natural refrigerant carbon dioxide (CO2) and is available in several configurations. At the top of the range are the BHP-FV37YD and BHP-FV46YD, two fully automatic models featuring direct mains-pressure hot-water delivery. They have storage capacities of 370 liters and 460 liters, respectively.
The 370-liter model is designed for households of around three to five people, while the 460-liter unit is aimed at households of four to six people.
Hitachi has not yet disclosed full efficiency specifications for the two new models. Their predecessors, the BHP-FV37WD and BHP-FV46WD, have annual hot-water and heat-retention efficiency ratings under Japanese Industrial Standards (JIS) of 4.2 and 4.1, respectively. The 370-liter predecessor uses a BHP-HAV45W heat pump unit, while the 460-liter version uses a BHP-HAV60W unit.
The manufacturer has not indicated whether the Y-series models feature a new compressor, refrigerant circuit or heat-exchanger architecture. Based on the specifications disclosed to date, the products appear to be an upgrade of Hitachi’s existing EcoCute platform rather than a new heat pump design.
One of the main changes in the Y series is expanded compatibility with Japanese electricity tariffs that encourage consumers to shift electricity consumption to daytime hours.