Which outcome occurs when a refrigeration system mixes R-410A with legacy mineral oil?

💡 Explanation

When R-410A is mixed with mineral oil, lacking miscibility causes the oil to separate and thermally degrade at high compressor temperatures, forming varnish deposits that stick to valve surfaces preventing proper sealing and thus compressor failure. Therefore valve failure occurs, rather than icing, pressure drop or valve blockage which involve different refrigerant properties interactions.

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