Performing an A/C System Inspection

Mitchell McAfoose, Parts & Service Manager, Fyda Freightliner Barkeyville
July 2017

Several items can be inspected on your a/c system to ensure optimal efficiency and performance.

Start with the a/c compressor clutch. When the clutch is not engaged there will be a gap between the clutch and the compressor. When the clutch is powered it will move towards and contact the compressor, engaging the compressor. The clutch uses the belt drive system to rotate the internal components of the a/c compressor. If this gap is too large, the clutch will fail to engage fully and will not allow the compressor operate to its full potential. This will also cause premature failure of the compressor. In most cases, the clutch can be replaced separately from the compressor and at a low cost.

A visual inspection of the condenser is necessary. It's important to ensure that it is not blocked or restricted by dirt or road debris. Also check the condition of the fins and make sure there is not any physical damage.

Inspect all hoses and fittings for signs of leaks. Inject a/c dye into your system and let the system run. A UV light is best for visual inspection of a/c dyes. If you have a sleeper cab, don't forget to check under your bunk. The evaporator inside could also be leaking.

If you have access to gauges, run your system and check pressures. Normal pressures will depend on the outside air temperature and humidity. For 80-degree outside air with a/c compressor engaged, normal pressures are between 40-50 psi on the low side and 175-210 psi on the high side.

While your system is running, inspect all external components. Check for any spots or components that are icing over. This would indicate a restriction, and that repairs are necessary. The photo illustrates a needed repair to a line that is beginning to ice over. The repair to this particular problem was to replace the expansion valve.

Maintenance items that should be serviced include cabin air filters, receiver dryers, accessory belts, and Freon levels. Fyda Freightliner offers a large line of OEM and aftermarket maintenance items to ensure you are running at full capacity!

Take advantage of our A/C Tune-Up Special at all Fyda Freightliner service locations through August 31, 2017 for just $118.80. Let our factory-trained technicians help keep you cool this summer!