The Frigoblock product development team loves a challenge. Particularly when it’s posed by a customer seeking unique functions and features to help them unlock new business opportunities.

So, when customers came and asked for more silent electric units that didn’t compromise on cooling capacity, we were more than happy to help out. Fast forward to today, and Frigoblock is launching the EK Whisper Pro, a PIEK-certified transport refrigeration unit (TRU) that:

• Offers ultra-low noise operation during delivery and when connected to the grid
• Delivers no loss of cooling capacity in standard operation
• Is compact and lightweight with better performance, airflow, and serviceability

Let’s take a brief look at how the story unfolded.

Keeping the noise down

The conversation initially started around the topic of pre-cooling. A challenge that’s particularly acute for customers loading goods into trucks at night, before dispatch the following morning. In this scenario, the TRU needs to be working to not only bring the temperature inside the truck body down to set point – but also to maintain this setting before the engine is started. It’s a process that clearly benefits from silent operation when the TRU is connected to the grid, thereby avoiding any complaints from close-by neighbors.

Then, during the day, the same customers run trucks to inner-city destinations. Journeys that typically involve a large number of door openings with little time between each stop. That makes high cooling capacity important for recovering temperature inside the truck body. The good news here though is that the EK Whisper Pro allows full power for ‘normal’ road operations, with full control of the unit’s power and noise thanks to the inverter control.

As a result, customers can run in silent mode anywhere during the day and night to meet all regulations relating to noise pollution. This is a particularly valuable capability during PIEK hours (7pm-7am), where companies are forced by regulation to be silent. Which is why it was one of the three core outcomes imagined for EK Whisper Pro:

• Achieve a noise/decibel level of operation that was certified as PIEK compliant
• Deliver the highest levels of cooling capacity, airflow, and pulldown
• Give drivers the flexibility of operation, depending on route and time of day

Delivering silence and performance

To achieve these aims, Frigoblock went back to the drawing board in terms of both the unit’s design and the materials employed.

First, we needed to address the main source of noise in any TRU: the compressor. Noise that is caused by vibrations during operation, and with the EK Whisper Pro we’ve been able to reduce the speed of the compressor by half.

That’s easier said than done however, as such a move can drastically impact performance. But with the EK Whisper Pro, Frigoblock can actively demonstrate:

• The same level of airflow you’d expect from any of our units
• A refrigeration capacity of 9.5 kilowatts¹ in Whisper Pro operation
• PIEK noise compliance, with the unit running at less than 59 decibels²

A more compact design

The redesign also presented the ideal opportunity to act on feedback from both dealers and clients, to create a compact and lightweight unit that’s easier to service. To this end, Frigoblock engineers have developed an all-new housing for the EK Whisper Pro. Importantly, this is made from plastic rather than fiberglass, and the resulting robustness brings its own benefits:

• The increased (and certified) side impact protection on offer means that barriers are no longer needed to shield the unit, which in turn helps improve air flow and cooling performance
• The compact design of the EK Whisper Pro also ensures the unit takes up the least space possible when fitted underneath a vehicle’s chassis
• In addition, maintenance is improved through easier access to the unit’s internal components – and a simpler process for running diagnostics

Command and control

A final point to touch on is the control that EK Whisper Pro offers to Fleet Managers and drivers. As previously mentioned, the initial requirement underpinning the design was for ultra-silent operation during the PIEK timeframe of 7pm-7am. But when re-thinking the control logic for the unit, Frigoblock engineers also thought: “wouldn’t it be good to allow drivers to switch to silent running even when they’re not having to conform to local regulations?”

The answer of course is yes, which is why the software in the control unit contains the intelligence required (thanks to Frigoblock’s full inverter control) to ensure the best mode is always employed – with the driver able to adapt as necessary. For example, a truck may use the unit’s standard mode from a distribution center and along a motorway, with the driver switching (using the HMI interface inside the cabin) to ultra-silent when entering the inner city.

In addition, with EK Whisper Pro drivers can now automatically set and adjust ‘ultra-low noise’ times from the controller. PIEK legislation may be defined as 7pm-7am, but it’s often useful for our customers to be able to extend these timings (for example, 6pm-8am) to meet the demands of their clients. 

Push the boundaries of what’s possible with Frigoblock

With the EK Whisper Pro comes technology that’s flexible, adaptable, and highly sustainable, which makes it the perfect solution for multi-drop city distribution. It’s also a unit that doesn’t compromise on performance, as even in ultra-silent mode it’s able to deliver high cooling capacity while running fans and evaporators at full speed to ensure equal airflow throughout a cooling compartment.

These are capabilities that help open up new possibilities for Fleet Managers – and expand fleet utility even further.

If that sounds of interest to you, why not find out more by clicking here:

1) Measured under ATP conditions at 0/30º

2) Recorded at 7,5m distance, following PIEK measurement conditions