R-410A is classified as an HFC refrigerant and has no undesirable ozone-depleting properties because it does not contain any chlorine.
Comprised of an equal blend of HFC-32 and HFC-125, R-410A is a near azeotropic refrigerant mixture that exhibits a negligible temperature glide. This means the system can be topped off repeatedly without risk of fractionalization should refrigerant loss occur.
Because it is incompatible with mineral oil, R-410A systems use synthetic polyol ester (POE) oil. Unfortunately, POE oils are hydroscopic, meaning they readily absorb water. This can degrade the oil, causing harm to the entire system. R-410A systems should not be left open to the atmosphere longer than absolutely necessary.
The operating pressures of R-410A are approximately 50 to 70% higher than that of R-22. For example, a normally operating R-22 system will typically have a high-side pressure of 260 psig and low-side pressure of 76 psig, while a normally operating R-410A system will have a high-side pressure of 418 psig and low-side pressure of 130 psig.