Gas Charging in Split Air Conditioners (AC)

Page content

In the previous articles we was the factors affecting the location of the indoor and outdoor units of split AC, the installation of the indoor unit, the outdoor unit and the refrigerant tubing. In this article we shall see the final step of the installation of split air conditioner, the gas charging.

If the installation of the indoor unit, outdoor unit and the refrigerant tubing is done properly, the process of gas charging in the new split air conditioner is very simple. In fact in the new split air conditioners no process like gas charging is involved. In the new units, the indoor and the outdoor units are prefilled with the gas.

When indoor unit is connected to the outdoor unit via refrigerant tubing, the tip of tubing originally attached to the indoor unit has to be opened, which leads to the leakage of refrigerant that comes with the unit prefilled from the factory. Thus this gas cannot be used in the split air conditioner for the cooling purposes.

Gas Charging from the Outdoor Unit

The outdoor unit is also prefilled with the refrigerant or the gas from the factory. Most of the gas is filled in the condenser coil at very high pressure. Since the gas is filled at high pressure sufficiently large quantity of gas can be filled in the condenser, which is good enough to produce the desired cooling effect in the room.

Since the refrigerant is already present in the air conditioning system, we don’t have charge the extra gas, however, if the distance between the indoor and the outdoor units is large, some external gas charging may be necessary. The gas present within the outdoor unit has to be released to the whole system including the refrigerant tubing and the indoor unit. Thus in the new split unit there is no actual gas charging in real sense, it is only distributing the gas compressed in the outdoor unit to the whole air conditioning system.

There are two valves located at the lower end of the outdoor unit, one for supplying the compressed gas from the outdoor unit to the indoor unit and other one for receiving the return gas from the indoor unit. Initially, both the valves are closed. During gas charging both the valves are opened slowly. With this the refrigerant gets distributed in the whole air conditioning system including the indoor unit, the outdoor unit and the refrigerant tubing.

Checking for the Gas Leakages

The gas charged into the system is like the life blood for the whole unit. Even slight leakages of the gas can hamper the performance of the system and it continuous leakage can render the unit useless. Further, even the cost of the gas is very high, so its leakage will not only lead to the breakdown of the air conditioning system, but also high costs of repairing. Hence it is vital to check right at the installation of the system that there are no leakages of the gas.

The leakages have to be mostly checked at the joints of the refrigerant tubing. There are four joints in the split air conditioner: two at the indoor unit and two at the outdoor unit, connecting the refrigerant tubing and the indoor and the outdoor units. Since the gas is now present in the air conditioning system, it is at high pressure.

To check for the leakages soap solution is applied to the joints. If there are any leakages, you will see the gas leaking in the form of the bubbles and if there are no leakages the soap solution remains stable.

If there is some gas leakage the connections have to be tightened. If the leakage doesn’t stops, the leakage point may have to be dismantled and reinstalled.

Starting the Air Conditioning System

Once the gas has been charged in the air conditioning system and it has been checked for the leakages, the system can now be started. It is assumed here that everything is goes well with the installation. When the system is started you can feel the cool air coming from the indoor unit within a minute or two.

You can adjust the position of the louvers of the indoor unit to evenly distribute the cool air inside the room or you can keep them at fix position to divert the cool air in particular direction. You can also adjust the speed of the fan. If you don’t need the cooling effect, you can keep the AC on fan mode. Most of the settings can be done from the remote control.

This post is part of the series: Installation of Wall Mounted Split Air Conditioners

This is the series of articles that gives step-by-step guide for installation of split air conditioners. It explains various factors, like deciding location of the indoor and outdoor units, their installation, gas charging etc.

  1. Installation of the Split Air Conditioners: Deciding the Location of Indoor and Outdoor Units
  2. Installation of the Wall Mounted Indoor Unit
  3. Installation of the Outdoor Unit of Split Air Conditioners
  4. Installation of the Refrigerant Tubing in Split Air Conditioners
  5. Gas Charging in Split Air Conditioners