Warm air randomly comes out the car air conditioning vents, the problem is somewhat on and off.
Car Problem Diagnosis
When a car air conditioning system blows warm air in randomly fashion, this is an indication of two possible problems. The first one is that the car a/c unit has a failing compressor and the second one is that the a/c unit has a problem on the electrical system.
Let’s have a look first at failing compressor. The compressor is the heart of the car air conditioning system and the refrigerant moves through every components of the system because of compressor. Once the compressor fails, the flow of the refrigerant within the system will stop, thus a warm air will start to come out the the conditioning vents.
Now, another problem is when the air conditioning unit has electrical problem, usually a loose wire. When the wiring is loose, it can affect the components of the air conditioning system, the components will seize to function and can cause the warm air that comes out the air conditioning vents. However, once the wire regains contact, the affected air condition components will start to work making the air conditioning unit to function normally.
Possible Cause Random Warm Air Coming on Car A/C
Failing compressor, Electrical system problem.
All About Auto Recommendation
Bring the car to a reputable auto repair shop that specialized in car air conditioning system, and ask the mechanic to inspect the compressor and air condition wiring for any trouble and repair if necessary. Tell the mechanic that the problem is randomly encountered and that you have done your diagnosis.