German heat-exchanger manufacturer Walter Roller, which makes air coolers (evaporators) for commercial cabinet and cold-rooms among other products, has announced a new high-efficiency air cooler for CO2 (R744) commercial applications.
The ceiling-mounted DLK Next unit will offer up to 14kW (4TR) in cooling capacity and is available for systems with an operating pressure of up to 80bar (1,160psi), according to a statement from the manufacturer.
The DLK Next has been designed to meet the increasing demand for ceiling-mounted air coolers in commercial refrigeration applications and expands its range of “optimized evaporators,” the company added.
Available from June 2023, the DLK Next will eventually replace Roller’s DLKT Euroline Plus model.
Optimized for efficiency
The DLK Next is equipped with up to four high-efficiency, two-stage electronically commutated (EC) fans as standard. There is also an option to include fans with speed control, said Roller.
According to industry experts, EC fans are known to improve the efficiency of CO2 refrigeration systems.
“For complex cooling tasks and careful air-conditioning of sensitive refrigerated goods, the evaporator blocks are available with four and six rows of tubes in depth, which is accompanied by correspondingly large heat exchanger surfaces and thus lower dehumidification,” explained Roller.
“For deep-freeze applications, the units are offered in T-design with electric defrosting systems in block and tray.”
The DLK Next is also available for use with water and brine.
The DLK Next is characterized by its increased flexibility for installation, said the manufacturer.
“Among other things, attention was paid to an easy-to-install aluminum housing with practical and generously dimensioned cut out options to meet the diverse requirements of installation engineering,” it added.
This is complemented by flush ceiling-suspension stainless-steel brackets instead of mounting rails.
“Among other things, attention was paid to an easy-to-install aluminum housing with practical and generously dimensioned cut out options to meet the diverse requirements of installation engineering.”Walter Roller
To make installation and commissioning easier, the DLK Next includes a pre-installed electronic expansion valve with precise superheat control. According to Roller, this feature is refrigerant-agnostic and is pre-parameterized for 40 refrigerants, including CO2.
Compact air coolers
In addition to the DLK Next, Roller recently launched a range of “super narrow” air coolers for refrigerated cabinets. The new VM, VW and VD models are suitable for CO2, propane (R290) and brine systems.
The range includes EC fan technology, which Roller has said saves 80% of energy compared to previous models.