Refra, a Lithuanian manufacturer of natural refrigerant-based chillers, heat pumps and refrigeration equipment, has launched Oasis, a new standard line of propane (R290) water-to-water heat pumps and chillers.
As heat pumps, the line offers heating capacities from 34 to 516kW (9.7 to 147.7TR). As chillers, it offers cooling capacities from 26 to 410kW (7.4 to 116.6TR). In a dual-function configuration, a single system can provide both heating and cooling, with the user prioritizing the functionality.
“The problem with air-cooled machines is trying to get a 1MW [284TR] unit on top of a tower like the Burj Khalifa building in Dubai,” said Refra’s CEO Aleksej Pavšukov. “Our solution is to put a water-cooled machine inside the building, with the enclosure maintained under slight negative pressure to prevent refrigerant from escaping.”
Pavšukov outlined the new R290 line along with its safety features in an interview with Marc Chasserot, CEO and Co-Founder of ATMOsphere, at Mostra Convegno Expocomfort (MCE) 2026. The event was held March 24‒27 in Milan. ATMOsphere is the publisher of NaturalRefrigerants.com.
Standard range: The Oasis line offers four models featuring one to four refrigeration circuits. Each circuit is charged with less than 4.9kg of propane.
- Oasis Solo, with dimensions of 1,360 × 915 × 1,885mm (54 × 36 × 74in), offers 34‒151kW (9.7‒42.9TR) heating capacities and 26‒119kW (7.4‒33.8TR) cooling capacities, with a SCOP of up to 5.05.
- Oasis Twin, with dimensions of 1,980 × 930 × 1,900mm (78 × 37 × 75in), offers 112‒303kW (31.8‒86.2TR) heating capacities and 90‒238kW (25.6‒67.7TR) cooling capacities, with a SCOP of up to 5.13.
- For large applications with variable thermal demand, Oasis Tribus, with dimensions of 2,700 × 930 × 1,900mm (106 × 37 × 75in), offers 168‒454kW (47.8‒129.1TR) heating capacities and 135‒357kW (38.4‒101.5TR) cooling capacities, with a SCOP of up to 5.23.
- For continuous-demand large applications, Oasis Quad, with dimensions of 3,420 × 930 × 1,900mm (135 × 37 × 75in), offers 224‒516kW (63.7‒147.7TR) heating capacities and 180‒410kW (51.3‒116.6TR) cooling capacities, with a SCOP of up to 5.10.
Safety features: The unit’s design follows the European EN378 standard, with all refrigerant-containing components housed in a Class IV ventilated enclosure. However, Pavšukov credits consultants, especially in Norway and the U.K., for pushing the company to design the “safest” system it has ever developed.
- If the detector in the enclosure identifies a leak, the system automatically shuts down all non-ATEX components, while the ventilation system extracts the refrigerant. This makes it “impossible” for the refrigerant to come in contact with a spark, Pavšukov explained.
- Maintaining the enclosure’s pressure slightly below atmospheric naturally pulls air into the unit, further preventing flammable refrigerant from leaking into the surrounding environment.
- Mechanical differential pressure monitoring signals a ventilation fan failure if the enclosure reaches atmospheric pressure.
Leading out: To develop the line, Refra relied on its more than a decade of experience with green cooling technologies. The company carries the ATMO Approved Natural Refrigerants Label, recognizing it as a leading manufacturer of natural refrigerant systems and components.
- “We are always looking at what comes back,” Pavšukov said, adding that the company is changing the highest-risk components, even within the same product family, to make the systems safer and more reliable.
- In 2025 Refra supplied five air-to-water R290 heat pumps and one water-to-water isobutane (R600a) unit for a U.K. district heating project. The 1.6MW (455TR) hybrid system delivers up to 80°C (176°F) water to the existing heating network.
- Keelings Flowers’ Dublin facility, updated in 2023, uses a 380kW (108TR)-capacity R290 chiller and a 120kW (34TR)-capacity reversible R290 heat pump produced by Refra. The flexible design allows adaptable space configurations with adjustable temperature zones from 2 to 22°C (35.6 to 71.6°F).
Quotable: “At MCE, customers were excited to finally have a standard [R290] water-to-water product for projects where air-to-water solutions are not possible,” Refra told NaturalRefrigerants.com, adding that the company expects to sell around 300‒500 units in 2026.
“Our solution is to put a water-cooled machine inside the building, with the enclosure maintained under slight negative pressure to prevent refrigerant from escaping.”
Aleksej Pavšukov, CEO of Refra
