UpTime Tech Tips

Air Conditioning System Pre Season Inspection

With the summer weather fast approaching I'm sure your drivers will be calling you to get their air conditioning fixed. Nothing seems to generate a call faster from a driver than an air conditioning system that is not performing correctly or worse yet, not working at all!

With a pre season inspection a lot of unscheduled repairs can be prevented and your drivers can be cool and happy!

Several key items that can be inspected to reduce cost, driver complaints and unscheduled downtime are:

• A/C condenser. Inspect the condenser for accumulation of debris, restriction or cooling fins damaged that could result in poor air flow thereby reducing effective heat rejection and also possible overheating of the engine. Also inspect any additional coolers that maybe mounted before or after the condenser for restricted air flow, loose mounting or worn mounts. In severe dusty conditions it may be necessary to wash or blow out the cooling package to insure proper A/C function and prevent engine overheating.
• A/C lines. Lines need to be inspected for proper routing and clipping to prevent chaffing/rubbing that will cause lines to fail. Also many A/C line on today's trucks are comprised of both rubber and metal so it is important to insure that the metal portion is also properly secured to prevent vibration and rubbing that can cause a line to fail.
• Cab or Cabin filters. Restricted cab filters will reduce the air flow over the evaporator core resulting in poor performance and increasing the stress on the blower motors. In severe dusty conditions the evaporator core can also be come restricted and require cleaning. Inspecting and or replacing cab filters will insure proper air flow, reduced stress on the air conditioning components and a cleaner environment for drivers.
• A/C Compressor and Compressor Drive Belt. Close inspection of the compressor mounting bolts can prevent damage to the compressor. Loose mounting bolts will damage the compressor and ultimately lead to a failure due to increased vibration. Many new trucks only use one serpentine belt to drive the fan, alternator, and A/C compressor so it is vital to inspect the belt at every PM to prevent an unscheduled breakdown. While inspecting the belt or belts it is always a good idea to check all the tensioner's and idler pulleys.
• Recirculation Vents. Inspect the intake vents if your truck is equipped with them to insure they are not blocked or restricted preventing proper air flow to the evaporator core that will reduce A/C performance.
• Charge port Caps Verify that the charge port caps are the correct style for you truck and are in place and securely tightened. Charge port caps prevent a gradual loss of refrigerant and prevents A/C system contamination when an A/C machine is connected.

If you have a set of A/C gauges it is a good idea to hook them up during a pre season inspection and operate the system while monitoring operating pressures. The reading can then be compared to a temperature/humidity compensated pressure chart to insure the system is operating correctly before it is most needed.

Please consult your owner's manual or appropriate OEM for the correct A/C system information and specifications.

A/C systems should only be repaired by a properly trained and certified technician in accordance to the current EPA guidelines.

Should your truck require service please contact anyone of our nearby Hill International Service Departments to schedule your appointment for our factory trained and certified technicians to repair your truck.

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