You should check your vehicle’s A/C system BEFORE hot weather lands to be sure it is functioning properly and blowing cold air. The following tips on how to inspect your car’s air conditioning system has been offered
Note: Always be very careful any time you are under the hood while the engine is running. Stay off all rotating components with your hands, clothing, and hair, and always wear eye protection around a running engine.
1. With the engine on, does the compressor clutch engage when the A/C is turned on? If it does not, this actually indicates a low (or empty) refrigerant condition, or an electrical problem. Also, listen for rapid clicking or cycling noises at the compressor when the A/C is turned on. If this is occuring, it could also show low refrigerant or some other problems. Have it inspected by your service technician. (Note: Some A/C systems prevent compressor clutch engagement in low temperatures, typically at or below 40� F.)
2. Is the A/C system blowing cold air? Luke warm air or air that is hardly cooled at all could show a low refrigerant charge in the A/C system. Pressure gauges can be used to check the refrigerant charge. If low, include refrigerant to bring the system up to full charge.
3. With the engine still running and the A/C switched off, listen for knocking or rumbling sounds in the vicinity of the compressor. These could show a failing compressor clutch, and/or loose mounting hardware.
4. Are A/C parts mounting bolts in place and tightly secured? Nothing loose or rattling around?
5. Are caps mounted on the A/C system service ports? This keeps out dirt, and also offers a seal for refrigerant.
6. Inspect all belts for cracks, wear, and glazing. Have them changed at the first sign of any of these conditions. Also, inspect for belts that vibrate while the engine is running and the A/C is on. This may show a belt that needs to be tightened, or a defective automatic belt tensioner.
7. Check all A/C and cooling system hoses for cuts, abrasion, weak spots, and signs of leakage. Leakage from A/C system hoses is often seen by an accumulation of dirt and oil, particularly at connections and fittings.
8. Ensure the condenser (in front of the radiator) is free of any obstructions, such as leaves or insects. This could lower airflow, resulting in lowered A/C performance. You can rinse the condenser clean with a garden hose.