Outdoor reversible heat pumps for the production of chilled or hot water, with hermetic rotary scroll compressors, axial fans and plate heat exchangers. The NX-N Series Air to Water heat pumps produce chilled water down to -8 °C, and hot water up to +55 °C. The NX-N series has been optimized for high performance in heating for the Canadian climate. Operation is guaranteed with external air temperatures down to -15 °C during winter heating season and up to 46 °C during summer cooling season.