Mitsubishi Electric announced the MSZ-RZ R290 on 23 June 2025, describing it as a premium plus wall-mounted inverter heat pump system for residential and small commercial use1. The unit runs on R290, which the manufacturer calls a natural refrigerant with a Global Warming Potential (GWP) of 31. The announcement was published on the company's own Hub site and gives no UK price, no release date and no confirmed UK availability1.
The company states the system carries A+++ energy ratings for both cooling and heating, and cites superior COP and SEER ratings as the basis for reduced electricity consumption1. It gives a noise figure of 19 dBA at the lowest setting and a unit depth of 247 mm1. Built-in Wi-Fi and compatibility with the MELCloud app are listed for remote control and scheduling1. The company also states the integrated Plasma Quad filtration system removes dust, allergens, PM2.5 particles, mould spores and viruses, including 99.8 per cent of SARS-CoV-21. A 3D i-see sensor detects people in the room and adjusts airflow and temperature, and refrigerant sensor technology is included to detect leaks early1.
"It uses R290, a natural refrigerant with a Global Warming Potential (GWP) of just 3."
R290 is the refrigerant designation for propane, and its low GWP is the property that matters under the F-Gas rules that phase down higher-GWP fluorinated gases. Mitsubishi Electric describes the model as a future-proof solution that meets upcoming F-Gas regulations and sustainability goals1. The announcement does not state which F-Gas thresholds or dates the unit is designed against, and no independent test data on efficiency, noise or filtration performance is included1. The comparison between R290 and R32, the refrigerant used in most current UK domestic heat pumps, is set out in the site's guide to R290 vs R32 heat pumps, and the regulatory background is covered in heat pump refrigerants and the F-Gas rules.
| Feature | Figure given |
|---|---|
| Refrigerant | R290, GWP 3 |
| Energy rating | A+++ cooling and heating |
| Lowest noise | 19 dBA |
| Unit depth | 247 mm |
| Filtration | Plasma Quad, 99.8% of SARS-CoV-2 claimed |
| Controls | Built-in Wi-Fi, MELCloud app |
Why it matters for households
A wall-mounted unit of this kind provides both heating and cooling from one indoor unit, which is a different proposition from a purpose-built domestic heat pump that replaces a gas boiler and runs radiators or underfloor heating. The announcement does not say whether the MSZ-RZ R290 is intended as a primary heat source for a whole home, and no UK capacity figures, running costs or typical installation arrangements are given1. Households weighing a refrigerant with a GWP of 3 against the R32 used in most current installations can compare the two in the guide to R290 and R32 heat pumps. R290 is flammable, which affects where and how such units can be sited and serviced; the announcement refers only to built-in leak detection and does not set out installation restrictions1. For homes already served by a Mitsubishi Electric system, the wider range is described in the guide to Mitsubishi Electric heat pumps, and general background sits in the heat pumps hub.
What happens next
No UK launch date, price or availability has been reported1. Mitsubishi Electric directs readers to a product page for further detail1.
Sources1 cited
- A game-changing residential air conditioning system | Mitsubishi Electric, les.mitsubishielectric.co.uk