In this post, you’ll learn the step-by-step process of introducing R410A refrigerant into an air conditioner completely empty of refrigerant.
Step 1: Prepare the System
With the unit powered off, remove the protective caps from the service valves or pipe stems. Use an L-type wrench to open the valves.
Step 2: Use a Vacuum Pump
To remove moisture, improve efficiency, and extend the lifespan of the system, connect the yellow hose from the manifold gauge set to the vacuum pump. Then, connect the blue hose to the thicker pipe of the air conditioner.
Step 3: Start the Vacuum Process
Turn on the vacuum pump and quickly open the blue gauge valve to create a pathway between the blue and yellow hoses. This will allow air and moisture to be expelled by the pump.
Step 4: Monitor the Vacuum Level
If your vacuum pump has a built-in vacuum gauge, keep it running until it reads 500 microns of mercury. Before turning off the pump, close the blue gauge valve.
If using an independent vacuum gauge, connect it to the red manifold port and wait for it to read 500 microns of mercury.
Step 5: Without a Vacuum Gauge
If no vacuum gauge is available, monitor the blue gauge until it reads 28 inches of mercury. Continue the vacuum process for an additional 10 minutes before shutting off the pump and closing the blue valve.
Step 6: Check for Leaks
Wait 30 minutes to ensure system tightness. If the blue gauge pressure increases, there may be a leak.
Step 7: Prepare for Refrigerant Charging
With the unit still off and the blue valve closed, disconnect the yellow hose from the vacuum pump and connect it to the R410A refrigerant cylinder. Do not open the cylinder yet.
Since R410A is a gas mixture, always introduce it in liquid phase by inverting the cylinder.
Step 8: Purge Air from the Yellow Hose
To remove air and moisture from the yellow hose, connect the vacuum pump to the red gauge. Open the red valve and run the pump for 30 seconds. Then, close the red valve and turn off the pump.
Step 9: Verify Refrigerant Weight
If you have a scale, check the refrigerant weight requirement on the air conditioner’s label. Ensure the scale matches the required weight during the charging process.
Step 10: Begin Charging
Start introducing R410A by briefly opening and closing the blue valve. Repeat this process to charge the system gradually, reaching 80% of the required refrigerant weight.
Step 11: Complete Charging with the System On
To charge the remaining 20%, turn on the air conditioner and continue the process of opening and closing the blue valve until the final weight is achieved. Once done, close the refrigerant cylinder valve while the system is running.
Step 12: Recover Refrigerant in the Hoses
With the system on, close the thinner pipe’s valve to prevent refrigerant from flowing into the indoor unit. This will cause the blue gauge pressure to drop.
Step 13: Disconnect the Gauges
When the blue gauge reads zero, quickly disconnect it and simultaneously reopen the thinner pipe valve to restore normal operation.
Step 14: Final Checks
Remove the manifold gauges and use a clamp meter to measure the system’s amperage. Compare it with the air conditioner’s specification label to ensure proper operation.
