R290 Heat Pumps Expand Low-Carbon Heating Portfolio

Trane, a brand of Trane Technologies, has launched two high-capacity air-to-water heat pumps—FLEX N HP and ARIES N HP—designed to expand its R290 refrigerant portfolio and support low-carbon heating deployment. The systems target commercial and light industrial applications across Europe, the Middle East, Africa, Australia and New Zealand, where demand for electrified heating and boiler replacement is accelerating.

R290 Refrigerant and Extended Operating Range
Both platforms are engineered around R290 (propane), a non-ozone-depleting refrigerant with ultra-low global warming potential (GWP). By optimizing thermodynamic performance around R290, the units achieve high seasonal heating efficiencies across a broad operating envelope.

The systems are designed for continuous operation at ambient temperatures down to –20°C. FLEX N HP can produce leaving water temperatures up to 77°C, while ARIES N HP reaches up to 75°C. This extended operating map enables application in colder climates and supports high-temperature heating circuits, including retrofit projects replacing conventional boilers.

Seasonal Coefficient of Performance (SCOP) values reach up to 4.5 for FLEX N HP and up to 4.3 for ARIES N HP under typical operating conditions, supporting reduced operating costs and lower carbon intensity compared with fossil-fuel-based heating systems.

Modular FLEX N HP for Scalable Capacity
FLEX N HP is a modular air-source heat pump platform using full inverter scroll compressor technology to modulate output according to load demand. Units can be hydraulically and electronically connected in banks of up to six modules, enabling total heating capacities exceeding 700 kW.

The modular architecture allows staged capacity expansion as building loads increase. Its compact footprint and side-by-side installation capability minimize required plant space. Each circuit contains less than 5 kg of refrigerant up to 125 kW capacity, supporting compliance with safety requirements for flammable refrigerants.

The combination of inverter-driven compressors and modular staging enables load matching, improving part-load efficiency and seasonal performance in variable demand scenarios.

ARIES N HP for Retrofit Applications
ARIES N HP is a packaged, all-in-one solution with capacities up to 230 kW. The unit employs high-efficiency scroll compressors in a double-circuit configuration to maintain stable performance and smooth defrosting during low-temperature operation.

Its mechanical layout and dimensions align with traditional HFC-based systems, facilitating replacement in existing plant rooms without major structural modifications. This compatibility simplifies boiler or legacy chiller-to-heat-pump retrofit projects.

ARIES N HP integrates Symbio 800 controls with built-in cybersecurity features meeting AICPA Trust Services Security Criteria, addressing increasing digital security requirements in building management systems.

Safety Systems for Flammable Refrigerants
Given the use of R290, both platforms incorporate comprehensive safety measures. Each unit includes an ATEX-certified leak management system, safety relief valves and an optional gas-water separator.

The systems implement Trane’s SDS2E (Segregate, Detect, Stop, Signal and Extract) architecture to manage refrigerant risk. In modular FLEX N HP configurations, a mandatory safety interlock kit ensures adjacent units shut down in the event of a detected leak, providing additional protection in multi-unit installations.

By combining extended temperature performance, modular scalability and integrated safety systems, the FLEX N HP and ARIES N HP platforms expand Trane’s R290-based heat pump portfolio and address regulatory and decarbonization requirements in commercial heating markets.