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Heating Rods for Refrigeration Compressor Oil Heating

  • The refrigeration compressors are delivered in a standard execution with built-in heating coils or rod in the crankcase.
  • The purpose of the heating coil or rod is to keep the oil in the crankcase warm even during standstill of the compressor. This ensures a low content of refrigerant in the oil.
  • Too much refrigerant in the oil makes it loose its lubricating properties. This may lead to damage of the movable parts in the compressor.
  • Further, the danger exists that the oil, during start-up of the compressor, foams so vigorously that the lubricating pressure will disappear.
  • Before start-up the heating rod should be switched on for at least 8 hours.
  • The heating coil or rod must not be switched on if the oil level in the vessel is below minimum in the sight glass. While the compressor is operating, it is usually switched off.
  • Further, remember to switch off the heating rod if the compressor crankcase is opened for inspection.

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