Daikin has introduced the Daikin Altherma 4 EPSKS Series, a new addition to its residential air-to-water heat pump range. The units are available in 4, 6 and 7 kW capacity classes and are designed to heat mid- to highly insulated houses while also providing domestic hot water. The new models extend the Daikin Altherma 4 lineup launched in April 2025 and operate with leaving water temperatures of up to 70°C, supporting both underfloor heating and traditional high-temperature radiators.
The Daikin Altherma 4 is the company’s first residential heat pump developed to use R-290 (propane) refrigerant, which has a near-zero Global Warming Potential (GWP). The system includes dedicated safety components such as a gas separator to prevent refrigerant exposure, factory-mounted anti-freeze valves, a sealed switchbox, and a gas sensor with automatic fan operation. According to Daikin, these measures are designed to ensure safety during transport, installation and operation.
The units are designed to operate in a wide temperature range, maintaining heating performance at outdoor temperatures down to −28°C. The system can deliver space heating through radiators at 55°C and underfloor heating at 35°C, as well as domestic hot water up to 70°C. Cooling is also available. A leaving water temperature of 70°C/75°C allows the system to support traditional radiator emitters, making it suitable as a replacement for gas boilers.
Daikin redesigned the outdoor unit with more compact dimensions (H958 × W1220 × D535) to improve manoeuvrability during installation. Ergonomically positioned PCB components, factory-mounted parts, reduced water piping size, and lower minimum water requirements are intended to simplify installation. The exterior features a black louvered grille to reduce fan visibility and reflective panels designed to blend with surrounding environments.
The EPSKS series includes a new 5-inch colour touch-screen MMI interface with WLAN connectivity and remotely updated software. The interface allows installers to configure systems and remotely access parameters, while users can monitor energy consumption and adjust room-by-room temperature settings through the Daikin Onecta app.
Daikin also provides installer training for the Altherma 4 H with R-290 through its Stand By Me platform. The programme covers installation, commissioning, maintenance and repair and is part of the company’s safety policy for handling flammable refrigerants in residential environments.
