If you’ll be transporting refrigerated or perishable goods from one location to another, you’ll need a reefer for your trailer to maintain the correct temperature inside. But, before you can start using your reefer, it needs to be primed.
Below, we’ll highlight the exact steps you need to take to prime your Thermo King brand reefer. Keep reading to learn more!
What is Thermo King?
Many who are not familiar with trucking may not know what a Thermo King is. So, what is it?
Thermo King is an American manufacturer that provides temperature control systems, such as reefers, to truckers and other commercial vehicle drivers across the nation.
What is a Thermo King Reefer?
Before we show you how to prime a Thermo King reefer, you may ask the question: Just what is a Thermo King Reefer?
Originally developed by the ice cream industry in 1925, a reefer is a refrigeration unit that attaches to a semi truck’s trailer. A reefer is a necessary component of any tractor-trailer or other truck that will be transporting perishables and other temperature-sensitive cargo.
How Do Thermo King Reefers Stay Cool?
Reefers stay cool through a couple of different methods.
The most common cooling methods include:
- Cryogenic cooling
- Diesel-powered generators
Those that use cryogenic technology work with carbon dioxide ice, which melts over time to keep the trailer’s contents cool. Diesel-powered reefers, on the other hand, use a connected diesel gas reserve to cool the truck’s contents. Thermo King mainly uses the diesel-powered method.
What Is a Good Thermo King Reefer Option?
Their most popular reefers are part of the Precedent S-Series, which was developed in an effort to meet both Evergreen CARB and EPA emissions compliance standards.
Thermo King’s Precedent S-Series reefers provide an advantage to truckers trying to stay green: they do not include a diesel particulate filter, or DPF. DPFs are a part of nearly all diesel-powered vehicles and units, intended to reduce the overall amount of emissions that are released into the atmosphere.
With the Precedent S-Series, Thermo King has developed a way to maintain environmental compliance without sacrificing performance. If you’re looking to stay as green as possible while on the road, this type of reefer is your best bet.
When Do You Need to Prime a Thermo King Reefer?
Now that you know a bit about Thermo King reefers and Thermo King, you may be wondering when you need to prime them
Most Thermo King models, namely the Precedent S-Series, will prime automatically. Other older models, like the C-566, will need to be manually primed before you can use them for the first time.
How to Prime a Thermo King Reefer
Before your diesel-powered Thermo King reefer can be started for the first time, the fuel pump needs to be primed. Priming the fuel pump will also bleed the entire fuel system of any air inside.
There are a couple of different ways to prime your reefer, but Thermo King recommends the following method:
- To prime the fuel pump and bleed air from the fuel system without starting the engine, you’ll need to use the SR-4 controller unit. This allows you to operate only the fuel pump relay.
- Access “Maintenance Menu” from your SR-4 controller.
- From the Maintenance Menu, choose “Output Test.” Then, press “Run Relay.”
- After choosing “Run Relay,” press the lock key on your controller. This will allow the fuel pump to begin to operate.
- Let the fuel pump run for approximately five minutes before continuing.
- Once these five minutes are up, you can start the reefer’s engine through the usual controller functions.
Now, let’s see an alternative method.
Alternative Priming Method
If the above method doesn’t work for you for whatever reason, there is an alternative priming method that Thermo King suggests.
Here’s how to get started:
- Use your SR-4 controller unit to start the reefer as you normally would.
- It may take a few attempts before the engine actually starts, as the fuel pump will begin priming itself as you start the engine. It does this by filling the fuel lines and filter with diesel fuel, automatically bleeding out air in the process.
- Once your unit does start, you may see Alarm Code 20 on your controller unit. This is the system alerting you that the engine failed to start. If you do get this code, clear it before you continue to use the reefer.
After you complete one of the two priming processes outlined above, your reefer will be ready for use.
Final Thoughts
A reefer is an essential part of any truck or tractor-trailer that will be transporting cold, frozen, or perishable goods. It keeps your cargo at the correct temperature to ensure there are no temperature-related problems while dropping off your goods.
Before you start your reefer for the first time, however, you need to prime the fuel pump. If you’re using a Thermo King unit, you can do this easily by using your SR-4 controller unit.
