Frascold has introduced its new ATEX-HT series of semi-hermetic piston compressors, designed to support high-temperature heat pump applications with natural refrigerants such as propane (R290), butane, and isobutane. The compressors can reach fluid temperatures up to 135°C, addressing rising demand for low-emission heating and cooling solutions in both industrial and commercial settings.
Product Overview
The ATEX-HT line includes four compressor sizes—S, V, Z, and W—with volumetric displacement ranging from 33 to 206 m³/h and motor powers from 5 to 52 kW. These compressors are tailored for integration in reversible air-water and water-water heat pumps used in hospitals, wellness centers, shopping malls, and industrial process heating. The series is certified for use in ATEX environments and is compatible with hydrocarbons, offering flexibility and performance in high-temperature operating conditions.
The compressors offer maximum fluid temperature thresholds of 135°C with butane, 115°C with isobutane, and 85°C with propane. They also feature a wide modulation range, operating down to 25% of maximum capacity to match variable load demands efficiently.
Technical Innovations
Key developments in the ATEX-HT range include high-efficiency motors—with optional permanent magnet rotors for the S, V, and Z models—yielding up to 6% performance gains under high torque and low frequency. Valve plates have been reinforced to handle pressure differences exceeding 30 bar, and pistons are treated with an anti-friction coating to reduce wear, improve startup performance, and enhance durability in fluctuating plant conditions.
Additionally, the compressors use a specially formulated oil with additives optimized for hydrocarbons. This reduces refrigerant dilution and foaming, improves lubrication, and supports effective oil return, eliminating the need for regenerative heat exchangers.
“Frascold was among the first companies to recognise the potential of hydrocarbons for heat pumps and to focus on research and development to transform this intuition into high-performance and reliable solutions,” said Livio Calabrese, Sales and Marketing Director at Frascold. “The new ATEX-HT series is the result of our deep knowledge of the needs of the industry, also stemming from a long direct experience on the ground with customers, a continuous technological progress and strategic vision, which uses sustainable innovation as major competitive asset in order to reduce operating costs and actively contribute to our customers’ energy transition.”