Daikin launches Altherma 4 H, the first heat pump in its next-generation Daikin Altherma 4 range

London, 28th October 2026: Daikin has launched the Daikin Altherma 4 Hydrosplit (Altherma 4 H), the first heat pump in its next-generation Daikin Altherma 4 series. The new range introduces a redesigned outdoor unit with a modern full-width black grille, Quiet Mark-certified low-noise operation and next-generation controls, led by the new MMI-4 colour touchscreen controller. 

Designed with existing homes in mind, Daikin Altherma 4 H provides heating, domestic hot water and comfort cooling, with the flexibility to work with standard radiators in most homes, helping make the switch from a traditional boiler to low-carbon heating more straightforward.

Combining a sealed refrigerant circuit in the outdoor unit with an indoor hydraulic unit, Daikin Altherma 4 H brings together the advantages of monobloc and split design. Only water passes between the outdoor and indoor units, while homeowners can choose between a wall-mounted hydraulic unit andan integrated floor-standing option with a built-in domestic hot water tank.

The Daikin Altherma 4 H can deliver flow temperatures of up to 70°C for EPSKS models, and EPSK models reach up to 65°C when needed, allowing it to work with standard radiators in most homes and helping reduce the need for additional changes during a heating system upgrade. It can also operate in outdoor temperatures as low as -28°C, providing reliable heating through colder weather. What’s more, the Daikin Altherma 4 H achieves an A+++ energy label for space heating at both 35°C and 55°C flow temperatures, helping to reduce energy consumption, running costs and carbon emissions.

In the summer months, the reversible system can provide cooling during warmer weather, offering greater flexibility throughout the year. When paired with Daikin heat pump convectors, it can also contribute towards compliance with Part O of the Building Regulations, which addresses overheating in buildings.

The location and appearance of an outdoor unit can be important considerations for homeowners, particularly where space is limited or neighbouring properties are close by. Daikin Altherma 4 H has a Quiet Mark-certified outdoor unit with sound power levels from 47 dBA, helping to limit disturbance and support greater flexibility when planning an installation. In addition, its redesigned full-width black grille gives the outdoor unit a modern, understated appearance, helping it sit more discreetly within its surroundings.

“With Daikin Altherma 4 H, we’ve looked at what installers need throughout the process, from practical product design and straightforward commissioning to connected support. The result is a system that gives installers greater confidence when recommending and fitting a heat pump for each home.”

Daikin-designed safeguards 

Daikin Altherma 4 H uses R-290 refrigerant, which has a Global Warming Potential (GWP) of  only 0.02. To support its use in residential settings, Daikin has designed and manufactured a series of safeguards specifically for the unit, including a gas separator, sealed switchbox and gas sensor with automatic fan operation.

These provisions minimise the exclusion zone around the outdoor unit, giving installers greater flexibility when choosing where to site the system. That matters most in retrofit projects, where the space available outdoors can determine which options are open to a homeowner.

Simpler installation, commissioning and servicing

For installers, Daikin Altherma 4 H combines simpler installation, commissioning and servicing with digital tools that support maintenance and ongoing system optimisation. As the refrigerant circuit remains sealed within the outdoor unit, installers don’t need F-Gas certification to fit the system. Factory-fitted anti-freeze valves and an ambient temperature sensor, together with simplified wiring, also help reduce the cost and work required on site.

At the heart of the new generation is the MMI-4 controller, which features a 5" colour touchscreen designed to simplify both commissioning and everyday use. Clearer displays and more intuitive navigation let installers and homeowners see how the system is performing at a glance, while its design is consistent with Daikin’s Madoka and Onecta controls.

Alongside the MMI-4, the DCS-R online portal enables installers to monitor up to 190 operating parameters and adjust settings remotely. This can help them identify issues, optimise system performance and reduce unnecessary site visits. Improved access to internal components, including the printed circuit board (PCB), is designed to make servicing quicker and more convenient.

The system also works with the Daikin Onecta app, enabling homeowners to monitor energy use and control their heating, and is compatible with digital thermostatic radiator valves. Modbus/API connectivity and over-the-air updates also prepare the system for evolving smart home and flexible grid services, helping ensure it can accommodate future developments in connected heating technology.

Eligible installations can benefit from the Boiler Upgrade Scheme in England and Wales, or Home Energy Scotland grant and loan funding, helping qualifying households access support towards the cost of switching to a heat pump.

To install Daikin Altherma 4 H, installers need a Stand By Me account, the Daikin e-Care app and Level 1 R-290 training.