Four Common Reefer Unit Issues and How to Troubleshoot

Tags: For Drivers, Reefer

Refrigeration trailers, also known as reefers, play a large, dynamic part in the freight and logistics industries. Without reefers, temperature-sensitive goods can only be transported a matter of miles from their starting location. That’s not far when thinking about how many perishable goods these days travel hundreds of miles on reefers to arrive at their destination.

Like any trailer, reefer trailers experience occasional issues that require attention. Tending to issues with reefers is particularly important due to the sensitivity of transported products. If the issue relates to a reefer unit not cooling properly, cargo can become spoiled and unusable, which spells big losses for all stakeholders.

To avoid issues, it helps to be familiar with the most common problems associated with reefer trailers and what signs indicate that a reefer may need preventive maintenance. Drivers can benefit from in-depth knowledge about their reefers, especially since they are responsible for maintaining proper temperatures during transport. Here are a few common problems that arise with reefer trailers and how to approach them. 

How to Know a Reefer Unit May Not Be Cooling Properly

If you’re looking into reefer trailer rentals, you’ll want to first consider what goes into maintaining the trailer, particularly regarding its cooling capacity. Reefer trailers require a fair amount of investment, but because their demand is high, these trailers can be a worthwhile asset with some understanding of how they operate. 

Be Aware of Leaks

Leaks come in many forms, including fluid and air leaks. Since reefers contain several mechanisms that aid in the cooling process, there is potential for leaks in multiple areas. If a reefer unit is not cooling properly, checking for leaks is a good place to start investigating.

Fluid leaks

Fluid leaks are a common problem in vehicles. Of course, it’s always wise to check typical leak sites, like oil from the engine. But when it comes to cooling issues, you’ll want to look at areas that directly relate to the compressor and condenser and support the reefer’s cooling abilities. 

Check these places for fluid leaks if there is a noticeable change in reefer temperature:

• Equalizer tubes: Equalizer tubes control the flow of liquid refrigerant entering the evaporator. They are an essential component of the overall cooling system and one of the first places to check for fluid leaks. If there is a leak from the equalizer tube, it is cause for concern and may be the reason for ineffective cooling. 
• Cracked Cooling Hoses and/or Belts: Cracked, broken, or worn hoses can be a major source of concern if a reefer is not cooling properly. Many hoses and belts make up cooling systems, both for refrigeration and engine function. 

Also, check whether leaks happen continuously or only when the unit is ON or OFF. Leaks that occur at specific times may help diagnose the problem more quickly. 

Air leaks

Like fluid leaks, air leaks are a common problem in reefer trailers. If seals are ineffective, cool air can escape the trailer while warm air enters. It can be easy to miss air leaks if reefers aren’t receiving regular maintenance, so staying on top of routine trailer service is critical. 

The following are places to check for air leaks: 

• Broken Seals: Seals can be broken or cracked in many places, but they are most commonly associated with doors. Seals in other places, like air chutes, can also be broken or cracked. 
• Door Hinges: Also, be aware of door hinges. If they are broken or corroded, they may contribute to improper cooling. 

Calibration for Sensors

Sensors help alert drivers to changes in reefer temperature, but even the sensors themselves can have issues. If inaccurate readings occur or alerts are not timely, a reefer may not cool properly for an extended period, putting the cargo at risk.

Condenser

Condensers act as heat exchangers. Just as a radiator helps to maintain a stable temperature for a car’s engine, a condenser supports the maintenance of stable temperatures in reefer trailers. 

A condenser contains several components, such as coils, clamps, bolts, and tubes. Damage to any of these parts can be detrimental to the cooling system’s overall function.

Bulkhead Issues

Bulkheads are used to separate different types of temperature-sensitive cargo within the same trailer. If airflow through bulkheads is blocked or inadequate, it can affect different temperature zones within the trailer. This is particularly concerning if operators are shipping different types of goods that require different storage temperatures. 

Maintaining and Troubleshooting a Reefer Trailer

The first step to avoiding improper cooling in a reefer is to receive regular maintenance. Check with the manufacturer to ensure that your reefer is serviced at the recommended intervals. 

Generally, it’s best practice to have service checks done every 90 days. During the summer months, drivers may want to receive more frequent service as the cooling systems have to work harder. Addressing issues before they worsen will save time and money and keep operators on the road with more consistency. 

In addition to regular maintenance, it’s wise for drivers to begin each trip with an inspection of their own. It’s not uncommon to find small issues that can be addressed before loading cargo and thus prevent a lost shipment. Here are some simple items to check pre-trip:

• Check hoses, belts, and seals for cracks or wear
• Check for any visible leaks around or within the reefer or its compressor unit
• Ensure that doors close tightly and lock
• Check that displays are functioning and represent accurate measurements and temperatures

Drivers can use thermometer sensors in the trailer for an added layer of protection against a reefer with cooling issues. Placing sensors in different temperature zones and at the top, bottom, front, and back of the trailer will ensure that the temperature being measured matches the displays. 

Reefer trailers with sensors that have alarms can be very helpful for drivers so they don’t miss temperature fluctuations or maintenance issues. 

Reefer Troubleshooting

Drivers who regularly operate reefer trailers or other commercial trailers should be well-informed and educated about them. Knowing how to perform simple maintenance if there are issues on the road can help prevent serious problems with a shipment. 

One of the most important skills for troubleshooting is a thorough knowledge of how to read and interpret alerts from the cooling unit. Codes will indicate issues with certain elements in the reefer, such as the battery, belts, or pressure. 

In addition to understanding how to read and operate all equipment within the reefer, keeping a UV coolant leak detector handy is helpful. If a driver believes that a leak is occurring but can’t locate it by a simple eye test, a UV leak detector will illuminate the source of a leak. 

Rent or Purchase a Reefer

If you are looking to purchase or rent a reefer trailer, it’s important to first consider and understand the nuances of operating one to determine whether your investment will be worthwhile.

Hale Trailer offers a wide variety of reefer trailers for rent at 12 trailer rental locations. We also carry new and used reefer trailers from top manufacturers, including Hyundai, Great Dane, Utility, and Wabash. We pride ourselves on offering industry-leading customer service to help you choose the right commercial trailer for your needs. Contact one of our trailer experts to discuss your requirements and learn more about Hale Trailer’s services.