York absorption chillers and heat pumps use a natural refrigerant (water) and are driven by waste or other low-cost heat sources. The line uses a two-step evaporator-absorber/parallel flow design enabling a lower salt concentration, requiring less energy input. The evaporator and absorber are split into lower and upper sections. This creates two different pressure levels, enhancing absorption compared to a conventional cycle. The different pressure levels divide the cooling load and the absorption process into two parts. The two-part process is said to effectively save about 10% in energy usage when compared to a traditional, single-step evaporator/absorber design. As a result, absorption requires lower generator temperatures, producing less noncondensable gas and less purging frequency.