Replaced failed compressor on Heil H4A348AKA air conditioning unit. Recovered R-410A refrigerant using Fieldpiece MR45 recovery machine. Removed faulty Copeland ZP31K5E-PFV-830 compressor. Installed new compressor, applying POE oil. Brazed connections with nitrogen purge. Evacuated system to 500 microns with Yellowjacket 93600 vacuum pump. Recharged to factory specifications. Tested amperage draw and superheat/subcooling. Verified proper operation across all stages of cooling.