A driving career covering over 6 million miles hauling refrigerated freight across one of the hottest continents on the planet makes Australian owner-operator Bob McMillan well-qualified to haul temperature-controlled freight successfully.
More importantly, driving millions of miles across the vast Australian Outback has meant he has had to manage load temperatures and reefer motor maintenance carefully – all three simultaneously. Hauling what’s known in Australia as a B-Triple (see Figure 1), which has 46 wheels, Bob has operated reefer motors for approximately 25,000 engine hours, so who better to ask about the successful operation of specialized equipment?
Bob McMillan’s 10 tips for operating a reefer motor and hauling temperature-controlled loads:
These tips apply to any brand of reefer motor:
- Spare parts: always carry extra belts, fuel filters, and air cleaner elements (whether you can fit them yourself), as you can’t always access the right part in an emergency.
- Belts: renew all belts every third, fourth, or fifth full service, depending on usage. Belts are cheaper than rejected loads:
- When it’s time for a full reefer motor service, including an oil change and new filters, I always install new belts regardless of their condition.
- Off-season: If you carry dry freight in the off-season, always run your motor(s) for half an hour or so each week.
- Leaks: check all lines for fluid and air leaks weekly and keep the battery in top working order.
- Service intervals: Recommended manufacturer service intervals should also be observed, and Bob recommends every 1,500 engine hours. Also, check for software updates to ensure the reefer unit runs on the latest version.
- Gas: Ensure your reefer motor(s) are always gassed up. Keep an eye on the steel ball in the window on your air receiver dryer. Gas levels are good if it’s at the top of the window.
- Temperature settings:
- It would be best if you used continuous cycle mode when hauling produce instead of cycle-sentry. Produce loads need continuous air flow to handle the heat of product respiration. Continuous airflow also allows for a more consistent temperature throughout the trailer for the duration of transport.
- Cycle-sentry should only be used for frozen loads, as it can handle more significant temperature variances without damaging the product.
- Hot loads: Loads that have yet to be pre-cooled are inevitable, and regardless of the set point, you’ll have to lower the temperature as quickly as possible without damaging the product or reefer motor. I advise bringing the temperature down gradually, only some at a time.
- For example, if the set point is 46F and the load temperature is 60F, don’t set the reefer motor at 46F as soon as it’s loaded. Instead, put it at 55F initially, and then every few hours, stop and drop the set point a few more degrees until you reach the desired temperature.
- I recommend this because if you try to pull down the set point too fast, the coil will freeze up.
- Seals: Ensure your reefer trailer door seals and door hinges are not damaged.
- Air flow: on all produce loads, especially high loads like lettuce, where the grower always wants that extra row of boxes on top, make sure the air chute is not compressed, ripper, or torn. Improper air distribution will create cool and hot spots in the trailer, resulting in load damage.
This list is by no means conclusive, but it is based on years of on-road experience. Keeping reefer motors well-maintained and in top operating condition is vital to any carrier’s success in the temperature-controlled sector. It’s also great to consult your manufacturers’ warranty requirements, recommended service intervals, and best practices. Stay cool, everyone!
