A new generation of air conditioning systems is being premiered in the
B-Class. THERMATIC manual air conditioning (standard) and THERMOTRONIC comfort automatic air conditioning (optional) feature a host of improvements over their predecessors. The new air conditioning systems are noticeably quieter and generate markedly less vibrations, as the blower motor is mechanically decoupled from the housing with the aid of special rubber elements. The systems furthermore offer optimised air intake in snowy conditions and offer more manual blower levels.

The efficient use of drive energy also constituted a key development objective. The air conditioning compressor operates according to the actually prevailing requirements: in dry weather or at temperatures in which no cooling is necessary, the air conditioning system carries out automatic and infinitely variable lowering of the compressor output. For this purpose, the B-Class possesses a special window misting sensor in the base of the rear-view mirror which measures the window temperature and the interior humidity and is thus able to detect whether the window is misted over.

A further aid to the efficient use of fuel is an internal heat exchanger which enables a reduction in the drive power of the refrigerant compressor. Supply and return of the refrigerant take place in separate but adjacent channels. As a result of this separate channelling of the two refrigerant flows, the refrigerant in the supply channel undergoes additional cooling without consuming any additional energy.

The ECO start/stop function is linked to the air conditioning system, which monitors regulation of the interior temperature and then enables the stop function. Automatic air conditioning continues during stop phases.