What must be done before recovering refrigerant from an R-410A unit if your recovery/recycling machine contains R-22 refrigerant?

Before recovering refrigerant from an R-410A unit when your recovery/recycling machine contains R-22 refrigerant, it is essential to remove the R-22 from the recovery unit and change the filter. This measure is crucial because mixing different refrigerants can lead to contamination, which may affect the performance of the recovery unit and possibly violate regulations.

R-410A and R-22 have different chemical compositions and pressures, and their compatibility is not guaranteed. By removing the R-22 before attempting to recover R-410A, you ensure that the recovery process is safe, effective, and compliant with EPA regulations. Switching filters also helps to prevent any residual contamination in the recovery system that might come from the R-22.

Implementing these steps helps maintain the integrity of the refrigerants and the recovery equipment, ultimately leading to safer and more efficient handling of refrigerants.