Fig. 18.5. Installing a transition valve when refilling from a cylinder with a low refrigerant level
1. Unscrew the filling valve handle as far as it will go (the valve is open) and insert it into the filling cylinder.
2. Unscrew the handle of the transition valve until it stops (the valve is closed) and insert it into the filling valve.
3. Connect the filling hose (blue) to the transition valve.
4. Connect the low pressure quick coupling to the filling hose (blue).
5. Turn the filling valve handle all the way (valve closed) to pierce a hole in the cylinder.
6. Turn the handle of the transition valve and remove the air.
7. Connect the low pressure quick release fitting to the low pressure service valve (Fig. 18.6).
Fig. 18.6. Connecting the low pressure quick coupling to the low pressure service valve
8. Start the engine.
9. Turn on the air conditioner and set the air temperature control knob to the maximum cooling position (MAX. COOL).
10. Set the engine crankshaft speed to 1500 min⁻¹.
11. Tighten the handle of the transition valve (the valve is open) and fill the system with the required amount of refrigerant, observing the filling level through the sight glass.
12. After completing the refrigerant filling, unscrew the handle of the transition valve as far as it will go (the valve is closed) and remove the quick-release fitting.
(Original version of the article on the website MITSUBISHIMAN)