Car air conditioning does not cool: the most common causes

Air conditioning is especially important on hot summer days, but sometimes it doesn’t cool properly. You can find out what that can be and what you can do yourself in our article.

Car air conditioning – that’s why it doesn’t cool

When the open windows in the car are no longer enough, the air conditioning is used. However, if you find that the cooling effect is missing, you should go on troubleshooting. Below we present the most common causes:

  • Refrigerant: First think about when you last had your air conditioning refrigerant refilled. The consumption or loss of refrigerant is relatively low, but something is always lost over time. Therefore, you should have the amount of refrigerant checked every two years. You can only have refrigerant refilled in a workshop.
  • Condenser: The condenser ensures that the refrigerant releases the heat. Since it is installed in the front part of the engine compartment, it is often damaged by small stones. The stones can hit the condenser so quickly that you can seriously damage the thin slats. In this case, the condenser fails and the air conditioning no longer works. Have the capacitor checked in a specialist workshop.
  • Foliage remnants: Especially in the beginning of autumn, leaves collect in front of the cooler. The air conditioning will no longer work on the hot autumn days. You can remove the foliage yourself and then quickly find out whether it was the cause. Dirt can also clog the cooler and thereby prevent the cooling effect, so you should also clean the cooler regularly in summer.
  • Compressor: If all of the previous causes are not applicable to you, the compressor may be defective. It processes the refrigerant under high pressure. Your car’s compressor has many moving parts that can get stuck over time. This is particularly the case with older models and especially when the air conditioning system is used little. Have the compressor checked in the workshop.
  • Switch: A common reason that is neglected is a broken switch. You can easily find out whether the switch is defective. To do this, start your car and press the switch, you should now hear the compressor and the condenser. If there is no noise, this can indicate a defective compressor or condenser, but also a defective switch.
  • Tip: Always switch the air conditioner on even on cooler days, as this lubricates all moving parts. It also prevents the refrigerant from becoming moldy and causing a smelly smell. If you have the air conditioning serviced regularly, it will serve you well for a very long time.


Often the capacitor becomes unusable. Dirt clogs the honeycomb, reducing the effectiveness of the air conditioner, which is increasingly reluctant to regulate the temperature. Over time, under a dirty crust, the metal begins to rot and the part turns into a non-working one. Radiator contamination leads to overheating. The first sign that it’s time to wash is the spontaneous shutdown of the air conditioner when driving in city traffic jams. The problem disappears at speed.

Malfunctions in the air conditioning electronic system can be added to problems arising from dirt. Usually, these are broken contacts. Because of this, the high-pressure sensor may not work: it rises to a critical level and freon is discharged from the air conditioning circuit through the emergency valve. Air conditioning “does not blow” and does not cool.

A fully-sealed climate system loses up to 15% of the total refrigerant volume each year. Even a properly functioning air conditioner of a new car should be inspected once every 2-3 years. For a car older than 6 years, the check should be annual, because over time the gaskets of the joints wear out, and microcracks appear on the highways. There are several types of freon, depending on the year of manufacture of the car. As a rule, somewhere under the hood, there is a sticker informing about the type of refrigerant. Refrigerant oil is renewed with freon.

Flash Cash For Cars is a Cash for Cars Brisbane service that you would need if you were selling a junk car, old car or scrap car. We buy cash for any make or model, regardless of its condition and mileage. Contact us today and get cash for your car today. We are the only address for cash for cars in Brisbane.


      • captcha