It is important to keep refrigerated containers clean, especially when storing fresh or perishable materials. Similar to how our refrigerators and air conditioners get extra attention during spring cleaning, regular cleaning of refrigerated containers is essential to keep them in good shape.
Reefer containers are similar to refrigerators and AC units at home, so much so that they need love and care to operate efficiently. As the change of weather brings pollen, dirt, dust, and the start of humid warm air, regular cleaning is key to reducing the potential for mechanical issues down the road.
When considering how to start cleaning your refrigerated unit, Portables360 likes to break it down into two parts – the exterior and interior. The guide below will review how our units can be efficiently cleaned so they can run smoothly and use less energy, saving you time and money.
Cleaning the Exterior of a Refrigerated Container
The exposed components can be divided into three sections:
For Portables360 units, the compressor is not a major or time-consuming concern because the majority of the ones in our fleet are scroll compressors. These energy-efficient and quiet compressors are hermetically sealed, making it difficult for the weather and ambient conditions to impact the unit.
2. Compressor Fan
This is the large fan behind the grates on the outside of the container. Over time the fan, fins, and bearings get dirty and/or wear. A dirty fan (and components) can cause a louder fan operation, strain the motor, and speed up wear on the bearings.
3. Condensor Coils
The compressor pressurizes the refrigerant, turning it into a hot, high-pressure gas. This gas leaves the compressor and flows into the condenser coils.
This is where the refrigerant releases much of the heat. As it cools, the refrigerant changes from a hot gas to a hot liquid. The condenser fan pulls outside air through the coils’ metal fins helping cool the refrigerant gases.
As air passes through the coils over time, the dust, pollen, debris, leaves, etc. will accumulate and clog the coil and fins.
Clogged coils will not only put excessive wear on the fans, but the reduced airflow limits the refrigeration units’ efficiency. Moreover, it could cause the system to overheat and shut down.
Cleaning the Compressor, Compressor Fan, and Condensor Coils
Cleaning the three components is simple: simply turn the unit off using the power button (Thermo King units) or I/O toggle switch (Carrier). Once the unit is powered off, you can remove the metal plates using a Phillips head screwdriver or socket wrench. You can also clean without removing the plates.
Next, with the unit turned off, take a low-pressure hose (i.e. garden hose) and rinse the fan and the coils until the water runs clear. You can flow the water upward through the fins or down/outward from the fan blades. Make sure to fully rinse as many rows as your water can access.
Finally, replace the metal plates/grate and turn the machine back on.
Once the unit is back on, we always recommend forcing it into a manual defrost. This will activate the heater on the evaporator coils, and melt any accumulated ice. This cycle can run from 5-to-20 minutes and will automatically return to the normal operating cycle.
Cleaning the Interior of a Refrigerated Container
The reefer units are equipped with two massive evaporator fans hidden behind the inside back panel of the unit. Most people don’t realize how much air enters the unit every time the doors are opened. When on, these fans are circulating and pulling return air from the box and doorway when the doors are open.
While we always recommend powering down while entering/exiting the unit, we know that’s not always feasible. To limit the air exchange as much as possible and Portables360 installs vinyl curtains at the doors. Meanwhile, the air entering the unit is “wet” air that typically cycles directly to the evaporator fans and freezes on the evaporator coils.
Regular defrosting cycles help to reduce the ice coating on these coils. Similar to the dirt on the condenser coils, ice on the evaporator coils will both limit airflow and make it difficult for the unit to drop and/or maintain low temperatures.
Separate from the defrost cycles, we always recommend customers consider the occasional full-box defrost. To do this, you have to remove all cargo, set the temperature to 70°F, and operate the unit for 24 hours. This will melt any accumulated ice on the coils and/or ice that settled on the ground in front of the supply vent.
We also recommend checking the drain holes inside the box. Every box is equipped with 4 drain holes at each of the interior corners. The finite screen and/or float balls frequently get clogged and limit the amount of water expelled from the interior.
There are many ways to clean the drain holes, such as:
- Compressed air
- Pressurized water
- Simply pulling the drain gizmo from the hole and rinsing it
Portables360’s fleet is the youngest in the marketplace, therefore requiring less ongoing maintenance than any other leased unit. That said, seasonal cleaning is about taking steps to ensure your unit is energy efficient and removes any debris or contaminants inside the unit that may damage your future cargos.