Fig. 10.1. The heating and ventilation system with climate control in E-class models is equipped with two filters (1) with activated carbon and one filter (2) for cleaning the air entering the passenger compartment. The carbon filter housings are located behind the fan, the dust filter is located in front of the fan. Due to this, the air is also cleaned in recirculation mode
The car is equipped as standard with an automatic heating system with electronic control and a filter for cleaning the air entering the passenger compartment, with separate adjustment for the driver and front passenger, which is traditional for Mercedes cars. An air conditioner or climate control system can be installed as additional equipment (Fig. 10.1).
On E-Class models with six- and eight-cylinder engines, as well as on all vehicles with air conditioning, an additional electric pump is installed to improve the circulation of fluid in the heating system.
Fresh air enters the heating system through the inlet under the windshield. The air passes through the heater body and is distributed by a system of various flaps through separate air ducts to the ventilation deflectors. When the heater is set to heating, the system flaps in the engine compartment open access to the heater radiator. The radiator is located in the heater body and is heated by hot engine coolant. The incoming air, passing through the hot radiator plates, is heated and then supplied to the passenger compartment.
Control and regulation device is located in the center of the instrument panel and consists of two rotary temperature controls and an electronic temperature setting system. The set temperature values (given values) are compared by temperature sensors with current values (actual). Depending on this, the double valve is controlled. The opening period is related to the difference between the set and actual temperature values.
Circulation valve (double valve) is located in the mounting block on the right side of the engine compartment. The double valve consists of two interdependent electromagnetic valves installed in a single block. Each valve is installed in the coolant circulation system and opens access to it through the corresponding heat exchanger. So, for example, if full power is needed for heating, the valve is open constantly. On the contrary, when the heating is off, the valves are closed. When the temperature is regulated automatically, the valve can often be heard working with the ignition on. Through an electrical contact, voltage is supplied to both magnetic coils of the valves. The magnetic anchor moves downward under the influence of the magnetic field, and the valve seat blocks the flow of coolant. When voltage is not supplied, the valve is open.
Circulation pump is installed under the air filter on the right side of the engine compartment. When the ignition is on and the heating system is running, the pump pumps the coolant through the heat exchanger. At the same time, it supports the main coolant pump. After the engine is stopped, the circulation pump continues to maintain the circulation of the coolant independently. Thus, heating can occur until all the heat from the engine is used up. The pump connection circuit is protected by fuse No.3. Connection to the "ground" is carried out through the automatic control and adjustment device of the heating system.
Article text obtained from the website mercedesman.ru