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Corrosion in Refer system

  • Moisture can cause corrosion. However, moisture in combination with a HCFC refrigerant containing chlorine (like for example R-22 or R-409A) creates much more serious corrosion, as the chlorine hydrolyses with the water to form hydrochloric acid (HCl) which is aggressive to most metals. Heat adds significantly to the problem by accelerating the acid-forming process.
  •  For HFC refrigerants (like R-404A or R-407C), it is the polyolester oils that are very hygroscopic and may decompose at high temperatures forming hydrofluoric acid with the moisture which could be introduced to the system through a sub-standard refrigerant.

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