R134a Air Conditioning Recharge Instructions
1. Preparation
1.1 Turn the knob on the hose with the piercing valve (large dial) fully to the left to retract the needle completely.
1.2 Connect the hose with the pressure gauge to the can by screwing the knob onto the can’s thread.
Do not move the needle while connecting!
1.3 Ensure that the engine is running and the A/C is turned on in recirculation mode, at maximum fan speed and lowest temperature. Then, open the hood.
2. Charging Process
2.1 Connect the quick coupler on the hose with the gauge to the low-pressure port (LP) on the vehicle’s A/C system.
This port is usually marked with a blue or black cap and the letters “LP”.
Hold the can upside down (valve facing downward).
2.2 Check the pressure in the system using the pressure gauge:
If the pressure is between 25–45 psi, no recharge is needed.
If the pressure is below 25 psi, continue to the next step.
2.3 Filling the system
Turn the knob clockwise to lower the needle and open the check valve – the refrigerant will begin to flow.
Fill the refrigerant gradually, by turning the knob slowly to control the flow.
During filling, the pressure on the gauge may temporarily rise – this is normal, as the gas has not yet fully expanded.
Stop the filling process once the pressure reaches the recommended level or the can is empty.
3. Finishing the Procedure
3.1 Disconnect the hose from the vehicle’s A/C system.
3.2 Turn off the engine and the A/C.
3.3 Check the temperature of the airflow inside the vehicle – it should feel cold.
3.4 If the air is not cold, repeat the pressure check (step 2.2) to determine if an additional recharge is needed.
R1234yf Air Conditioning Recharge Instructions
1. Preparation
1.1 Turn the large dial on the hose with the valve fully to the left to fully retract the needle.
1.2 Connect the gold R1234yf adapter to the quick coupler on the pressure gauge hose.
1.3 Screw the other end of the hose onto the R1234yf can by tightening the dial onto the can’s thread.
Do not move the needle during this step!
1.4 Make sure the engine is running and the A/C is turned on in recirculation mode, at maximum fan speed and lowest temperature. Then, open the hood.
2. Charging Process
2.1 Connect the gold R1234yf adapter (already attached to the quick coupler) to the vehicle’s low-pressure port (LP).
The LP port is typically marked with a blue or black cap and labeled “LP”.
Hold the can upside down (valve pointing downward).
2.2 Check the pressure in the A/C system:
If the pressure is between 25 and 45 psi, no recharge is needed.
If the pressure is below 25 psi, proceed to the next step.
2.3 Filling the system
Turn the dial clockwise to lower the needle and open the check valve – the refrigerant will begin to flow.
Add refrigerant slowly, by turning the dial gently to control the flow.
During charging, the pressure gauge may show higher values temporarily, because the gas has not yet fully expanded.
Stop the filling process once the pressure is in the recommended range or the can is empty.
3. Finishing the Procedure
3.1 Disconnect the hose from the vehicle’s A/C system.
3.2 Turn off the engine and the A/C.
3.3 Check the airflow temperature inside the vehicle – it should feel cold.
3.4 If the air is not cold, repeat the pressure reading (see step 2.2) to determine if an additional recharge is necessary.