Signs of Low Freon in Car

The compressor in any vehicle’s air conditioning system operates with a gas (Freon) that has been compressed by the compressor. The Freon returns to its original form and reaches temperatures well below zero degrees Fahrenheit when the compressor decompresses it. Temperatures similar to those outside, coupled with the air coming in through the windows, are what reach the interior of the car.

This is why Freon is so critical in any refrigeration system, as, without the refrigerant gas, the system would not cool or heat as well as it should, and could even cause compressor damage in certain cases.

The air conditioner will not work effectively if the Freon level in the car is too low, so we must constantly maintain the proper amount of gas in the vehicle. Here we look at 7 signs of low Freon level.

What Is Freon?

All refrigeration systems, including those used in automobiles, rely on refrigerants to maintain a comfortable cabin temperature. More than a brand name, Freon is a substance used in automotive air conditioning systems that have been associated with refrigerants for many years. Arsenic, fluorine, hydrocarbons, and bromine are the main components of this substance.

Freon is a refrigerant gas that helps cool and heats the air blown by an air conditioner. It is possible for a low Freon level to not only cause the air conditioner to malfunction, but also to cause other components to fail.

Signs of Low Freon in car

1. Car A/C Comes Out With Hot Air

Warm air coming out of the vents indicates low Freon levels. As mentioned above, your car’s air conditioner circulates refrigerant under pressure.

Amounts that are too low eventually impair performance. As a result, the system blows hot air. This means that Freon levels are too low or have disappeared.

2. Air Conditioning Gauge Reading

On the air conditioning system, connect a pressure gauge to the high side and low side service ports. The high side gauge hose connects to the high side service port of the vehicle. This hose connects to the low side (blue) service port on the high side of the gauge assembly.

Depending on how the knobs on the gauge are turned, the readings range from 80 to 105 psi when the engine and air conditioning are off. When the engine is running and the air conditioner is operating at full throttle, the pressure ranges from 25 to 35 psi. The gauge should register between 200 and 350 psi. Low or near-zero figures imply a total loss of the data set.

3. Coolant Leak

Look for any apparent refrigerant leaks during your inspection. Refrigerant leaks are an important indication of low Freon levels. In the case of a coolant leak, the fluid has the appearance of a “thin” greasy liquid.

Refrigerant leaks are usually found under the hood, in the engine compartment, or at the compressor location. You should take any refrigerant leak to a local repair company as soon as possible.

4. Ice In The Compressor

A brief layer of ice on the compressor indicates a low Freon level in most cases. What causes this? During this time, water will take the place of Freon. However, if you are a skilled technician, you should be able to quickly load Freon into the vehicle, to be more accurate.

5. Loss of cooling capacity

As mentioned above, the air conditioner uses a large amount of refrigerant to cool the vehicle.

The cooling system suffers when your vehicle’s Freon is low. If you think the air conditioner is not blowing, you are probably driving a car with low Freon levels.

6. AC Clutch Fails To Engage

When you turn on your vehicle’s air conditioner, you should hear a “click” from the clutch. If the Freon levels in the system are too low, the clutch will not engage. Due to the shortage of refrigerant, the compressor cannot properly pressurize the system.

The clutch “click” has a specific meaning: it senses the amount of Freon in the system and allows the compressor to pressurize the system accordingly.

7. Unclear liquid moving sight

In modern automobiles, a sight glass model is used that allows the coolant flow to be seen. It would be possible to see the liquid hand, the high-pressure points, and the movement of the liquid. A fully charged device has the ability to operate accurately and smoothly. However, the presence of bubbles or a blurred appearance may occur when the refrigerant level is very low.

How to add Freon to car Ac

It is necessary to recharge an air conditioner once it has been determined that it has run out of gas in order to maintain proper operation. To do this, consider the following actions:

Step 1: Find the inputs of the system or circuit.

First and foremost, locate the circuit inlets, which are usually two pipes (one high-pressure and one low-pressure), each of which has a plug that needs to be unscrewed.

The high-pressure pipe is the thinner of the two pipes, while the low-pressure pipe is the wider of the two. If they are not obvious to the naked eye, it is advisable to consult the instruction manual for more information.

Step 2: Connect the machine to the circuit

Connect the hoses to the low and high-pressure ports of the pressure regulator. The pressure gauge on the unit should initially show readings between 8 and 10 bar during first use.

However, before connecting the circuit, check that all other hoses are tightly closed.

Step 3: Open the conduits

After checking that the connection is secure, the next step is to open the hoses to allow air to flow through them. However, only one of these should be done at a time, not both at the same time.

Open the hoses only until the marker rises a few points above the ground. The goal is to prevent the howitzer from rupturing and gas from leaking through the hoses as the howitzer is disconnected from the pipeline.

Step 4: Recover gas and vacuum

This procedure consists of recovering the gas residue and cleaning the area afterward. This is a simple procedure that only requires opening the low and high-pressure ports of the device and pressing the green button.

To recover the gas after self-cleaning, it is essential to open the green valve on the side of the tank. Once this procedure is completed, the suction will run for a total of 20 minutes.

Step 5: Check the pressure

Check that the pressure gauges on the equipment, both low and high pressure, are set to -1 bar. If the gauge starts to rise slowly, the gas leak may still be present.

If this is the case, stop the process and inspect the circuit to determine the source of the problem in order to perform a successful gas recharge.

Step 6: Recharge

Once the circuit has been completely closed, continue with the gas recharge, which starts when the red button on the machine is pressed for a while.

Always have at hand the exact amount needed by the vehicle; this amount will appear on a label on the engine.

Step 7: Check that the A/C is working

Close the valves once you have finished recharging the system and check if the air conditioner is working properly.

In addition, you should block the hose channels. It is essential that you turn on the cooling system and set it to maximum capacity. If the airflow is strong and the room is cool, this indicates that the task has been successfully completed.


How Often Should I Recharge My Car’s AC System?

Although there is no definitive solution, most mechanics suggest charging the Freon in the car’s air conditioning unit every two to three years.

How Much Does It Cost To Recharge A Car’s AC System?

The cost of charging the car’s air conditioning device ranges from US$200 to US$300, depending on the size. Note that the cost of replacing any part of the air conditioner may be higher.

How Much Freon Should I Add To The AC System?

To determine the actual volume of Freon that can be absorbed by the car’s air conditioner, refer to the owner’s manual or the details under the hood.

Is Freon Flammable?

Freon is not flammable, but it is very toxic. Wear safety gloves and then goggles, and load the car’s contact device with more Freon.

Final Thoughts – Signs of Low Freon in Car

Using one or two cans of refrigerant in the car’s air conditioner until the summer is over will not be enough. Using more refrigerant than the manufacturer advises will also cause further damage.

Freon leaks usually indicate an internal problem that requires the replacement of one or more components.

This guide should help you identify and resolve any low Freon problems you may have.

Liam Dare

As CEO of, my passion for the automotive world motivates me to build online businesses that provide information and entertainment to users. I am proud to contribute in a positive way to the automotive community.