Line Set Cleaning for R-410A Retrofits, Refrigerant Conversions, and Compressor Burnouts
When converting R-410A from R-22 and using the same line set it is necessary to thoroughly clean out the system by flushing it. There are several varieties of flushing solutions available from your AC supply which will effectively flush oil, moisture, acid and other impurities from any HVAC system and completely evaporate from the system during evacuation prior to charging. These flushing solvents can be used for both Air Conditioning and Refrigeration systems requiring R-410A retrofits, refrigerant conversions, and compressor burnout cleaning. They can be used with all refrigerants and compressor coils. To flush a system thoroughly:
1. Use a flushing solution from your AC supplier or R-11 kit and safety equipment including gloves and goggles.
2. Recover the R-22 from the system.
3. Disconnect any power leads.
4. Using a tubing cutter, cut the suction and liquid lines at both the condenser and evaporator.
5. Temporarily connect the liquid and suction lines at the evaporator using clear plastic tubing and hose clamps.
6. Put a clean container at the outlet of the liquid line at the condenser to catch solvent and contaminants as they are purged from the system.
7. Connect the flush can using the hose.
8. Connect the refrigeration service hose to the can valve and to the suction line outside with injection tool and rubber adapter.
9. Invert the flush can and dispense a 15-20 second burst. Inspect the clear tubing at the evaporator and look for liquid. If no liquid is present continue 15 seconds until liquid is observed. Follow flush solution with a regulated supply of dry nitrogen and push the solvent into the receiving container while observing the condition of the material. When you see that the solvent is clear, the flushing is complete. Follow with a dry nitrogen purge.
10. Connect the line set to the new evaporator and condenser and evacuate and leak check and charge per factory specifications.