Is an Oil Injected Compressor Really Better?
In fact, oil-free compressors are preferred in extreme cold because there's no worry about the oil turning to sludge. On the other hand, oil-injected compressors may be desired if working in extreme heat and humidity, because they can dissipate heat more quickly in a given duty cycle and resist rust build-up.
Different compressors use different lubrication techniques. In screw compressors, the oil is often pumped into the moving parts, while pistons and scrolls often employ splash lubrication using oil from a vessel in the bottom of the compressor.