Why Is Your Car Air Conditioning Blowing Hot Air?


car air conditioning button, car air conditioning blowing hot airKeeping your car air conditioning working properly is an important part of maintaining your vehicle correctly.  If you find your car air conditioning blowing hot air unexpectedly it’s important to get it fixed to avoid further damage to your system.  For example, if your systems aren’t working due to a leak, leaving the leak open will allow debris and contamination into your system which will lead to future problems.

Why is my car air conditioning blowing hot air?

There are a few reasons you might be experiencing hot air from the vents of your car and the process for fixing each type of problem is very different so we’ll talk through each potential cause separately.

  • Ventilation System Problem
  • Electrical Problems
  • System Leaks

Ventilation System Problem

Many air conditioning problems are not really air conditioning problems at all but are really ventilation system problems.  In today’s cars, your ventilation system problem has its own control module, much like the computer that controls your engine, except this module controls a series of servo motors that move flaps and doors around in your ventilation system.  If the module has a fault in it, a door breaks or servo motor malfunctions it can cause your ventilation system to skip blowing the air over the evaporator so it never gets cooled and feels like your air conditioning is broken. The best way to diagnose this problem on new cars is to take your car to a mechanic so they can use their scan tools to communicate with the ventilation system module.

Electrical Problems

Like most of the systems in your vehicle, the air conditioning system relies on electrical signals from the control module as well as sensors in the system to work properly.  If any of these signals are interrupted it could cause you to find your car air conditioning blowing hot air. The most common problems are an interruption of the signal for the compressor clutch to engage or a problem with the signal for the AC condenser fans to turn on.  If there is a problem in either of these circuits it will leave your perfectly good AC system inoperable. If you suspect this is your problem try reading our article about diagnosing electrical problems!

System Leaks

Leaks are the most common problem with air conditioning systems in cars.  Air conditioning systems leak due to the high pressures and the volatile nature of the refrigerant used.  Even with normal maintenance, air conditioning systems can leak. Small leaks are usually noticed by a slow reduction in cooling power until you’re left sweating.  Large leaks usually result in an immediate loss of cooling and should be fixed quickly to keep debris out. If you’re looking for a quick fix to seal your leak without having to replace any hard parts, consider using Red Angel A/C Stop Leak to seal your leak quickly and without any tools!  Simply locate the low-pressure port in your system, connect the included coupler to your system and inject our powerful combination of stop leak formula and refrigerant!
Red Angel AC Stop Leak & Conditioner

You can find Red Angel A/C Stop Leak at any of our partnering local auto parts stores like:

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car_air_conditioning.jpg – by Coffeekai – Licensed by Getty Images – Original Link

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