Climate Change in the Actros

Mercedes-Benz Trucks - Driving Experience Slovenia 2015

Procurement, Development and suppliers. Together, they developed a new auxiliary air conditioning unit for the Mercedes-Benz Actros in the space of just two and a half years. Two components were added to the existing concept.

The Mercedes-Benz Actros has just been given a new auxiliary air conditioning system that is lighter, smaller and more cost-effective than its predecessors, with a maximum output of 2.5 kW. This was made possible by a newly developed, electric A/C compressor featuring unique technology. The Development and Procurement functions of Daimler Trucks and Buses were working together to find a supplier with a suitable technical solution. They ultimately found what they were looking for at the Japanese automotive supplier Sanden. The company developed the first ever automotive, 24-volt A/C compressor for Daimler.

Design and components of the electrical auxiliary air conditioning system.

Two new components

The typical auxiliary air conditioning system of the time was replaced by two components: an electric refrigerant compressor and a blower fan module in front of the A/C condenser. When the engine is running, the compressor is powered mechanically by a flat drive belt. The compressor condenses the refrigerant to a high level of pressure. This heats it up. If the vehicle is stationary, the electric refrigerant compressor provides this function. The heat generated during compression is removed in the A/C condenser. When the engine is off, it does this using a blower fan module. The expansion valve located directly next to the evaporator relieves the pressure on the refrigerant. This allows it to absorb heat at low temperatures and pressures. The driver’s cab is cooled to a pleasant temperature, even when it’s sweltering outside.

More space, less consumption

The system does away with a cold reservoir and rear wall unit, which was previously used to blow cold air into the cab. This is now done by the electric auxiliary air conditioning system. This means that there are no longer any recesses in the paneling of the rear wall, giving the driver unrestricted use of the top berth. The stowage compartment underneath the cab on the left-hand side is also accessible again. The new system is also much lighter, weighing 53 kg less than the previous system. This benefits the payload. The compressors, blower fan module and vents are powered by the vehicle’s battery. Cool air can be generated for up to eight hours at a time. Recharging the battery takes less energy than charging the cold reservoir. The fuel consumption of the Actros is improved.

Omitted components in electric air conditioning system.

In just two and a half years, Procurement, Development and suppliers have developed and implemented a state-of-the-art air conditioning system. The only new thing is the electric A/C compressor. Those involved in the project were otherwise able to make use of the existing technology. This is another thing that they are all proud of.

Apr 20, 2016
Nadescha Vornehm