The oil separator reservoirs type OSR and BOS2-R are the basis for the design of a space saving high pressure oil management system. The oil separator reservoirs are equipped with sight glasses and a shut off valve.

Installation and start up
During the start up of the system the oil reservoir should be charged with compressor refrigeration oil up to the upper sight glass. The charging can be done via the oil separator part. Oil should only recharged if the oil level drops below the lower sight glass.

FL1 – Operation with R717 (ammonia) and R290 (propane)
ESK oil separator reservoirs types OSR / BOS2-R can be approved for hazardous fluids on request and are to be ordered with suffix -FL1. OSR units for R 290, R 600a, R 717, R 723 and R 1270 applications and BOS2-R units for R 290, R 600a and R 717 applications will be fitted with welding adapters instead of rotalock valves


Max. allowable operating pressure (PSmax) according to the temp. range
[1] Allow. operating temperature: 140 … –10°C → PS1: As per table
[2] Allow. operating temperature: –10 … – 40°C → PS2: As per table