Air Conditioning System — General Information and Precautions (BMW 3 Series E46)

General information

1. The air conditioning system can be installed on any model. It cools the air in the cabin and reduces its humidity, making the atmosphere in the cabin more comfortable and eliminating the cause of fogging of the windows.

2. The cooling part of the system works like a household refrigerator. The compressor, which is driven by a belt from the crankshaft, compresses the gaseous refrigerant and forces it into the condenser, located in front of the radiator. In the condenser, the gaseous refrigerant cools and turns into a liquid state. The liquid refrigerant passes through the expansion valve into the evaporator, where it again changes from a liquid state to a gaseous state. This transformation is accompanied by a drop in the temperature of the refrigerant, due to which the evaporator cools. The gas from the evaporator again enters the compressor and the cycle is repeated.

3. The evaporator is a heat exchanger through which outside air is blown. The air in the evaporator is cooled and enters the mixing chamber. Here it mixes with the warm air that has passed through the heater radiator, thereby achieving the required temperature in the cabin.

4. The heating part of the system works the same as in a system without air conditioning.

5. The system operates under the control of an electronic unit with a self-diagnostic function. If any malfunction occurs in the system, it is recommended to contact BMW service station specialists.

Precautionary measures

6. If the car is equipped with an air conditioning system, then when working with the system itself or when performing work with other systems that require disconnecting or partially disassembling the air conditioning system, it is necessary to observe certain safety precautions. If it becomes necessary to disconnect the air conditioning system at some point, do not do it yourself under any circumstances - contact service station specialists.

Warning! The refrigerant is potentially dangerous and must be handled by a trained professional. It can cause frostbite if it comes into contact with the skin. The refrigerant itself is not poisonous, but in the presence of an open flame or even a lit cigarette it forms a toxic gas. Uncontrolled discharge of the system is dangerous for people and equipment.

Warning: Do not use the air conditioner if you know it is not fully charged, as this may damage the compressor.

This publication was borrowed from an online resource «BMWMAN»