Evacuating the Refrigerant CircuitUpdated 13 days ago

Introduction

Follow this guide to properly evacuate the refrigerant circuit in your air conditioning system.

Air and foreign matter in the refrigerant circuit can lead to abnormal rises in pressure, which can damage the appliance, reduce its efficiency, and cause injury. 

Use a Micron or Torr gauge to evacuate the refrigerant circuit, removing any non-condensable gas and moisture from the system. 

Perform the evacuation after the initial installation and when relocating the system. 

Notes

General Note

When opening valve stems, turn the supplied Allen wrench until the valve stem comes into contact with the stopper. Do not try to force the valve to open further. 

Caution

Only qualified personnel may evacuate the refrigerant circuit, as this system uses R-454B refrigerant.

Prerequisites

• Confirm the pipes connecting the indoor and outdoor units are properly attached. 
• Ensure all electrical wiring is connected properly.

Steps

1. Discharge the oxygen-free nitrogen. Evacuate the system to 8,000 microns (8 Torr) using all service valves. 

2. Break the vacuum by introducing nitrogen into the port connection (liquid and gas lines) until achieving positive pressure. 

3. Evacuate the system to a reading of 5,000 microns (5 Torr). 

4. Break the vacuum again by introducing nitrogen into the port connections (liquid and gas lines) until achieving positive pressure. 

5. Evacuate the system to reading of 500 microns (0.5 Torr). 

6. Hold the vacuum without movement for a minimum of 4 hours to ensure a moisture-free system. 

7. If the vacuum fails to hold, repeat the steps until it does. 

Reminder: Insulate the Refrigerant Piping Joints

Once the refrigerant circuit is evacuated, remember to insulate the refrigerant piping joints. 

For instructions, click this link.