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How to Fill Gas in Split AC

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Most people, especially in the summer, use air conditioners to be cool and comfortable. The heat from the room is absorbed by the refrigerant, which is a fluid, gas, or liquid, and the hot air is expelled into the environment. It's worth noting that there would be no air conditioning, refrigeration, or freezing technology without refrigerant.

After confirming that your air conditioner is in good working order, you will require a refill to allow you to continue moving and in the event that the gas level in the air is low. The toxin or chemical used to aid the cooling process is known as air conditioning gas. They house the air conditioner coils, which help to humidify the indoor air.

The gas used to refuel the air conditioner comes in a variety of forms. Since the gas is trapped within the coils of an air conditioner, it allows for air conditioning. These liquid gases are extremely efficient since they effectively chill and dehumidify the indoor air. The process of re-filling the AC gas, on the other hand, is extremely dangerous and necessitates extreme caution and safety precautions.

Before we get into how to fill gas in split AC, it's necessary to understand a few different types of AC gases because not all air conditioners use the same refrigerant.

Types of Gas Used as Refrigerant in Air Conditioner

Among various types of gas used as refrigerants in AC, the following three popular ones are provided below. 

1. Puron (R410A): Puron (R410A) is a hydrofluorocarbon gas that is extensively utilized in modern air conditioners. It has no negative impact on the ozone layer and is widely used as household air conditioning. The gas has a high heat transfer efficiency, allowing the AC unit to make less effort for the same amount of cooling. In addition, the gas operates at very high pressure.

2. Freon (R22): Freon (R22) is a hydrochlorofluorocarbon (HCFC) gas. It contributes to the ozone layer's depletion. For domestic air conditioners, this sort of gas is not recommended. It is well known to have negative environmental consequences.

3. R32 refrigerant: This refrigerant is a low-GWP, zero-ozone-depleting refrigerant that is somewhat combustible.

It's important to remember that the refrigerant in air conditioners is poisonous and can easily cause frostbite. As a result, it's critical that you read the highlighted precautions listed below before starting the procedure of refilling the AC gas. These liquid gases are extremely efficient since they effectively chill and dehumidify the indoor air. The process of refilling the AC gas, on the other hand, is quite dangerous, and caution is advised.

Precautionary Measures

Make sure you're always wearing gloves. 

Since your eyes are very important, use protective eyeglasses.

Required equipment


To create a vacuum, a vacuum pump is utilized.

A unit of power

A set of gauges for AC manifolds.

How is the Air Conditioner Gas Filling Procedure?

Having factual tools and safety attires, filling AC gas is usually a very easy thing. 

•To begin with, you will be required to check and locate the low side that is the suction line and the discharge line too that is the high side from the air conditioner.

•The two are usually set behind a window AC and in a riven AC in the out-of-doors unit. The suction line is chilly to the touch and is located directly above the discharge line. The discharge line, on the other hand, is warm to the touch and is placed beneath the suction line. The suction line will be used to recharge the gas into the AC.

•To enable you to fix the lines, you will be needed to unscrew the bolts of the suction line. Loosen the screws to let the gas out since these screws act as the valve used to draw the gas. The screw is efficient, and it won’t let the refrigerant flow in or out until it is closed. However, to enable you to refill the AC gas, you will have to loosen the screw.

•To connect the blue hose of the AC, loosen the bolt on the left side and then connect the blue hose of the AC manifold gauge to the port you unscrewed. Ascertain that the yellow pump is linked to the vacuum pump. After everything is in place, be sure that all of the air has been removed from the system. This step must be handled with caution since any moisture that gets inside the compressor can damage it.

•Check and confirm that all of the valves on the AC manifold gauge are completely closed. The yellow pipe is then connected to the refrigerant tank. Loosen the yellow hose at the manifold end slightly. Make sure there is no air inside the hose, and always double-check this by opening and closing the cylinder knob. This will aid in the discharge of any trapped air inside the pipes. Remember to tighten the yellow hose after that.

•Before turning on the air conditioner, open and close the manifold's low side knob. After that, turn on the air conditioner and wait for the compressor to kick in.

•At this stage, it is prudent to maintain a close eye on the gauge. Because you will have to open and reopen the compressor for a few seconds when it starts. Also, keep an eye on where the pressure settles in the gauge; you'll need to constantly opening and shutting it to ensure efficacy. You must repeat the operation until the pressure reaches 60-70 PSI.

•Keep in mind that releasing all of the gas at once might easily damage the compressor, which is why the AC refrigerant is loaded in little volumes.

•When the pressure reaches 60-70 PSI, close the manifold valve. After that, you close the manifold valve and the refrigerant tank knob. Finally, remove the blue hose from the suction line as well as the yellow hose from the refrigerant tank.


As written above, now you know everything about how to fill gas in split AC, refilling, and the types of gases used, and the precautions to take. Maintaining your air conditioner with all of its services will help you use it for the long term. 

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