Oil carry- over in compressor units

by Martin Wierbosch

The combination of older compressor units and modern oils can cost problems such as the well known oil carry-over. In the good multistage oil separator, this problem is solved but what should you do with your existing compressor unit?

Buy the new one? Modify the old compressor unit? This could be quite expensive. Get used to the oil carryover? This is also expensive. Think about higher maintenance costs than budgeted and a higher failure rate for the E-motors.
In this case I would recommend installing the After Oil Separator (AOS) into your existing compressor unit.
The After Oil Separator has all characteristics of the multistage oil separator, and it can be installed in the common discharge-line. In this way, the After Oil Separator can handle more than one compressor units. Captured oil can be routed to the compressor with the lowest oil level.

However, in some cases there is no need for the extra installations, the manual adjustments in the compressor unit can solve the problem.
One of our customers spent a lot of time and money changing parts and hiring specialists to check his system and repair problems. The answer was found in a small area: the adhesion between oil and refrigerant was too heavy. As you know, every oil separator system works better if the adhesion between refrigerant and oil is as weak as possible.

In case of our customer, we adjusted the compressor aggregate with one small valve and brought the balance back.

Sometimes the compressor aggregate, just like the human body, has some reserve that can be used. In other cases some extra help is needed.
If the installation shows limitations there is always a possible upgrade to the multi stage After-Oil Separator.

The After Oil Separator operates in the same way as the multi stage oil separator, and it is suitable for frequency controlled compressor units, where not only the amount of gas volume changes but also the temperature after compression due to the amount of gas volume.

If you wonder if your compressor unit can be improved, fill the form” UNIT information sheet” and give us a call. We can evaluate your compressor unit free of charge.

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