2008 Mercedes R-Class Owner's Manual - Page 220

Controls in detail Climate control Air conditioning The air conditioning is operational while the engine is running and cools the interior air to the temperature set by the operator. In addition, the air conditioning dehumidifies the interior air at outside temperatures above 41°F (5° C) and helps prevent window fogging. Press button 9 ( page 210). The indicator lamp on the button goes out. Activating Moist air can fog up the windows. You can dehumidify the air with the air conditioning. Press button 9 ( page 210) again. The indicator lamp on the button comes on. The air conditioning uses the refrigerant R134a. This refrigerant is free of CFCs which are harmful to the ozone layer. Residual heat and ventilation With the engine switched off, it is possible to continue to heat or ventilate the interior for up to 30 minutes. This feature makes use of the residual heat produced by the engine. i How long the system will provide heating depends on the coolant temperature the battery voltage Regardless of the temperature and air volume set on the climate control panel, an interior temperature is aimed at by 72°F (22°C) and the blower runs on low speed to protect the vehicle battery. i Condensation may drip out from underneath the vehicle. This is normal and not an indication of a malfunction. Warning! G If you turn off the cooling function, the interior air is not dried. The windows can fog up more quickly. Window fogging may impair visibility and endanger you and others. ! If the air conditioning cannot be turned on again, this indicates that the air conditioning is losing refrigerant. The compressor has turned off. Have the air conditioning checked at the nearest authorized Mercedes-Benz Light Truck Center. Activating Switch off the ignition ( page 39). Press button 9 ( page 210). The indicator lamp on the button comes on. Deactivating It is possible to deactivate the air conditioning (cooling) function of the climate control system. The air in the vehicle will then no longer be cooled or dehumidified. 219