Charging the AC system with a large container of refrigerant along with an accurate weight scale and manifold set is a reliable technique. This method of charging the AC system requires more technical knowledge than using the AC machine because of the process of opening and closing valves as well as allowing the vehicle’s AC system to operate during the operation. However, a skilled person can charge the AC system with high levels of quality and accuracy if the proper steps are followed. The correct charge amount must be known before beginning the process and can be found on the AC decal or from a reliable database source. Follow these steps to charge the AC system.
Charging the AC System with a Large Container
1. See the previous steps on pulling a vacuum with the electric pump or with the pneumatic pump. These steps must be followed prior to charging the AC system with this method.
2. Place the container of refrigerant on the electric scale.
3. Remove the cap from the container and connect the yellow hose from the manifold set to the port on the container.
4. Open the valve on the container and carefully loosen the yellow hose connection to purge the air from the hose. Quickly tighten the hose connection as soon as any hissing sound is present.
The manual valve on the refrigerant container is opened by turning counterclockwise. The yellow hose should be slightly loosened at the manifold to purge the air from the
The yellow hose from the manifold set is connected to the threaded fitting on the refrigerant container. This connection should be tightened to a secure torque using a firm
5. Press the power button on the scale and wait for the warm-up process to finish. The scale used in this process moves to a zero setting after warming up and will begin displaying the amount being charged when the valves are opened.
The refrigerant scale is turned on by pressing the on/off button. After warming up, the display shows a 0 amount and will begin displaying the amount that exits the container when the valves are opened. This makes it easy to see how much refrigerant has been added to the AC
6. Open the blue and red valves on the manifold to allow the refrigerant to move from the container into the vehicle’s AC system. The scale will begin to show the charge amount immediately when this process begins.
The blue manifold knob needs to be turned counterclockwise to allow the yellow hose to feed refrigerant into the blue hose and the low side of the AC
The red manifold valve knob must be closed off to prevent high side system pressure to be directed into the container of refrigerant when the vehicle is started and the AC is turned
7. Once the process slows down, the red valve on the manifold needs to be closed (turned clockwise), the vehicle can be started, and the AC system is turned on.
The red manifold knob needs to be turned counterclockwise to allow the yellow hose to feed refrigerant into the red hose and the high side of the AC
8. The charging process will continue due to the low side pressure being lower than the pressure in the container. Allow this process to continue until the correct amount of refrigerant has been added to the vehicle.
The electronic scale provides a digital readout of the amount of refrigerant that is being added to the vehicle. Using this tool allows an individual to charge an AC system to the exact desired
9. Once the correct amount of refrigerant has been added to the vehicle, close the valve on the container and then close the blue valve on the manifold (turn clockwise).
The engine is started and the AC is turned on to assist in the manual charging process by lowering the pressure in the low side of the AC system. This low pressure in the low side of the AC system will cause refrigerant to move from the container to the AC system on the
When the vehicle AC system reaches the correct level, the valve on the refrigerant container needs to be closed and the blue manifold valve should be turned clockwise to close off the
10. The AC system is now charged and the pressures can be evaluated along with the duct temperatures to determine if it is operating as designed.
