Mazda CX-9 Grand Touring 2009 Manual page 1734

Fig. 3: Identifying Charging Preparation
Courtesy of MAZDA MOTORS CORP.
EVACUATION
1. Open all the valves of the manifold gauge.
CAUTION:
2. Start the vacuum pump and let it operate for 15 min.
Fig. 4: Starting Vacuum Pump
Courtesy of MAZDA MOTORS CORP.
3. Verify that high-and low-pressure side readings of the manifold gauge are at - 101 kPa {-760 mmHg, -
29.9 inHg}. Close each valve of the manifold gauge.
2008 Mazda CX-9 Grand Touring
2008 HVAC Refrigerant System - Mazda CX-9
Close the manifold gauge valve immediately after stopping the
vacuum pump. If the valve is left open, the vacuum pump oil will
flow back into the refrigeration cycle and cause a decrease in
the efficiency of the air conditioner.