Mazda RX-8 Workshop Manual page 2569

WARNING:
If charging the system with refrigerant by service cans or refrigerant tank,
running the engine with the high–pressure side valve open is dangerous.
Pressure within the service cans or refrigerant tank will increase and they could
explode, scattering metal fragments and liquid refrigerant that can seriously
injure you. Therefore, do not open the high–pressure side valve while the
engine is running.
20. Start the engine and actuate the A/C compressor.
21. Open the low–pressure side valve of the manifold gauge and charge with refrigerant until
the weight of the refrigerant tank has decreased 430 g {15.2 oz} from the amount in Step 13.
22. Close the low–pressure side valve of the manifold gauge and the valve of the refrigerant
tank.
23. Stop the engine and A/C compressor.
24. Inspect for leakage using a gas leak tester.
If there is no leakage, go to Step 26.
If leakage is found at a loose joint, tighten the joint, then go to next step.
25. Inspect for leakage again.