Cleaning your outdoor coils on AC or Heat Pump system, Here is proper step that should be taken when your Professional AC Technician comes out for annual maintenance or Tune up on the A/C equipment.
Step 1 Shut off power to AC unit by shutting off breaker at the main panel or
the disconnect by Air Conditioning Equipment
Step 2 Remove the top of AC equipment and any panels
Step 3 Remove any major debris
Step 4 Add special chemical to outdoor coils and let it sit on the coils and break up the hard dirt and calcium thats been baked on the coils.
Step 5 Hoses the coils and clean the system from the inside out and make sure the dirt and calcium is removed from the coils and fins
Step 6 Reassemble the AC equipment and clean up