Variant: oil cooler above compressor level

Usually the oil cooler should be located in the immediate vicinity of the compressor, preferably below the compressor / oil separator (Basic version: oil cooler below compressor level). A design with the oil cooler above the compressor should be limited to systems with relatively short shut-off periods: If the oil cooler is positioned considerably high above the compressor (e.g. oil cooler on roof, compressor in machinery room), oil can flow back from the oil cooler into the oil separator during standstill and be carried into the system during the subsequent compressor start. Therefore, as an additional safety measure, install the following components in the oil line: