TURBRO Mini Split Evacuation Step-by-Step Guide

Installing a TURBRO Mini Split (ductless mini-split air conditioner/heat pump) requires the evacuation (vacuum pumping) process as one of the most critical steps. It completely removes air, moisture, and impurities from the refrigerant lines and indoor unit, preventing abnormal system pressure, reduced efficiency, or compressor damage. TURBRO’s existing models follow a highly consistent installation procedure.

Important Safety Warnings 

• This procedure requires professional HVAC tools and experience. It is strongly recommended that a qualified technician perform the work.
• TURBRO Mini Split units are factory-precharged with refrigerant; evacuation is only for the piping and indoor unit.
• TURBRO Mini Split units use mildly flammable A2L refrigerants (such as R454B in the Greenland series or R32 in other series) — Recommend use a vacuum pump rated for A2L refrigerants. 
• Before starting, confirm that the refrigerant lines, power wiring, and signal cables between the indoor and outdoor units are fully connected and secure.
• Wear safety goggles and gloves. Keep away from open flames.
• Never turn on the air conditioner power during evacuation to avoid damaging the compressor.

Required Tools (Officially Recommended)

• A2L-rated vacuum pump (compatible with R454B/R32)
• Manifold gauge set (with compound pressure gauge reading down to -76 cmHg)
• Charging hoses
• Hex wrench (for valve operation)
• Soapy water or professional leak detector (for leak checking)

Vacuum Pumping Procedure 

1. Remove Protective Caps Remove all protective caps from the service port, low-pressure valve (gas valve), and high-pressure valve (liquid valve) on the outdoor unit.
2. Connect Equipment Connect the manifold gauge charging hose to the service port and attach the other hose to the vacuum pump. (Refer to the manifold gauge’s Handle Lo / Handle Hi valves.)
3. Open Manifold Low-Pressure Valve Open the low-pressure valve on the manifold gauge and keep the high-pressure valve closed.
4. Run Vacuum Pump Start the vacuum pump and run it for at least 15 minutes. Confirm the compound pressure gauge reads -0.1 MPa (approximately -76 cmHg—deep vacuum).
5. Close and Observe Close the manifold low-pressure valve and turn off the vacuum pump. Wait 5 minutes and verify that the pressure change does not exceed 0.005 MPa. (If pressure rises more, locate and repair the leak immediately.)
6. Brief Refrigerant Release Use a hex wrench to open the outdoor unit’s low-pressure valve counterclockwise 1/4 turn to release a small amount of refrigerant. Close the valve after 5 seconds and quickly remove the pressure hose.
7. Perform Full Leak Check Use soapy water (or a professional leak detector) to inspect all refrigerant pipe joints, the two outdoor valves, the service port, and any welded joints. Tighten flare nuts if bubbles appear and re-test until leak-free.
8. Fully Open All Valves Completely open both the low-pressure and high-pressure valves on the outdoor unit with a hex wrench. Reinstall all protective caps and valve covers (tighten to the specified torque using a torque wrench).

After Completing Evacuation:

• The system is now in a proper vacuum state, allowing the factory-precharged refrigerant in the outdoor unit to safely flow into the lines.
• Double-check all electrical connections, drainage pipe direction, and mounting security.
• Install the indoor unit air filter and front panel.
• Perform a final pre-power safety inspection (voltage, grounding, insulation resistance, etc.).

Common Issues & Helpful Tips

• Insufficient Vacuum: Extend the vacuum time to 30 minutes or check for leaks in the piping.
• Extra-Long Lines: For unusually long line sets, additional refrigerant may be required—refer to your specific model’s manual or contact TURBRO support.
• Triple Evacuation Method (Advanced Option): For best results, use dry nitrogen for a triple evacuation-break-vacuum cycle to remove even more moisture (recommended for professional installs).
• Test Run: After evacuation and leak checking, power on the unit and observe cooling/heating performance and any unusual noises.

Properly completing the evacuation ensures your TURBRO Mini Split delivers peak performance, maximum efficiency, and the longest possible service life. If you have any questions during installation, contact TURBRO support at support@turbro.com or consult a licensed HVAC technician.

This guide is compiled from TURBRO’s official installation manuals for reference only. Always follow the exact manual included with your specific unit.

Enjoy the perfect comfort from your TURBRO Mini Split! If you need installation videos, accessory recommendations, or more TURBRO tips, feel free to leave a comment below.