For all types of refrigeration equipment HOS BV uses various test protocols and quality standards.

How we test a Semi-hermetic refrigeration compressor:

  • Electric measurement (Megger) testing (resistance and insulation testing)
  • Oil filter is removed and oil quality is inspected
  • Compressor is run to build up pressure to 15 bar
  • For a number of hours compressor is then observed to check if the pressure does not drop (leakage test)
  • If pressure is maintained, pressure then gets released and compressor is put on 2 bar nitrogen pressure
  • Compressor then gets released for industrial cleaning
  • If so agreed with customer, the compressor gets a new paint job.
  • Compressor then gets packaged for safe transport


Electrical testing

We begin by performing a Megger test. The Megger device is used to test resistance and insulation. Meggers use a high-voltage, low-current DC charge that measures the resistance within wires and motor windings to identify current leakage and faulty or damaged insulation. With a Megger test, we can verify the integrity of the wires in a machine.

Oil filter is removed and oil quality is inspected

To inspect the quality of the oil, we first remove the oil filter. The oil filter gets a visual inspection to determine if the filter is still in good shape, or needs replacement. After that, the oil itself gets inspected to see if there is enough oil and if the oil is clean enough.

When the oil and filter are of expected quality, the compressor gets released for a pressure test.

Pressure test

After the oil is inspected and it is safe to run the compressor, we perform a pressure test. The compressor is run to build up pressure to 15 bar. For numerous hours the compressor is observed to check if the pressure does not drop. If the pressure is maintained, the pressure gets released and the compressor is put on 2 bar nitrogen. After this test, we can be assured of good functionality of the compressor. This is why HOS BV provides warranty for the compressor

Cleaning and painting

When a compressor passes all the quality checks, it gets sent to the cleaner. Here the compressor gets an industrial cleaning. In some situations the customer wants a new paint job, in which case the compressor gets transported to our spray booth to get painted to look as good as new.