When you turn on the air conditioner in your car, you expect to receive a flow of fresh, cold air. However, that’s not always what happens. A number of different problems can prevent your AC from blowing cold air into the cabin, and some are more serious than others.
Potential causes of hot air
As mentioned, there are many potential causes for your AC to blow warm or hot air into the cabin rather than cold, fresh air. These include:
Low Refrigerant: Low refrigerant will prevent your air conditioner from operating (the clutch won’t kick in and make the compressor cycle if the amount of pressure in the system is off). This is actually the single most common problem for an AC not to blow cold. Low refrigerant can stem from a number of things, including leaks and failed components.
Bad Clutch Cycling Switch: If the clutch cycling switch has failed, then the electromagnetic clutch on the air compressor won’t kick in, which means that the refrigerant cannot be pressurized and the system won’t work.
Blocked or Broken Condenser: The condenser is where the magic happens in your air conditioner and if it has been blocked up with debris or is damaged, you won’t get cold or even cool air from the system.
Restrictions in the System: What happens when you kink your garden hose? The water won’t flow, right? The same is true for your car’s AC system. If there’s a restriction somewhere in the system, it blocks it all up and prevents the AC from blowing cold.
While there are several potential issues, the most common is low refrigerant. The level of refrigerant in your system decreases naturally over time (very, very slowly), but leaks can also occur. If your AC isn’t blowing cold, it must be serviced by a licensed mechanic certified for HVAC (Heating, Ventilation, and Air Conditioning) work.