Automatic air conditioning system (BMW 5 Series E28)

1, 3 — Temperature control rollers for the left and right sides of the passenger compartment

The temperature control mode is switched on and off by a roller on the driver's side.

Left end position - temperature is not regulated, the supplied air is cooled as much as possible.

Rotate from the fixed position to the right - temperature regulation is activated.

Right end position (fixed) - maximum heating of the cabin, temperature regulation does not occur (this position can be used for emergency switching in case of a malfunction of the electronic temperature control system).

The scales indicate approximate values for the set temperatures. The selected temperature is reached extremely quickly and, as a rule, should not change. Turn the switch gradually to avoid unwanted temperature jumps.

2 — Switch and roller for regulating the amount of air supplied

Position 0 - the system is switched off, the air supply is blocked.

Turn to the right until it locks - the system is on, ventilation operates at minimum capacity. Further rotation to the right - the amount of air supplied increases.

Right end position (fixed) - maximum air supply (this position can be used for emergency switching in case of a malfunction of the electronic temperature control system).



4, 8 — Keys for switching on the automatic mode of distribution of supplied air for the right and left sides of the cabin



Air distribution occurs automatically depending on temperature conditions.

Air flows through the intensive heating deflectors of the windshield and front side windows, through the deflectors on the instrument panel and in the front doors, as well as on the upper side of the instrument panel, through the front nozzles into the footwell in the front and rear of the passenger compartment, and through the deflectors at the end of the center console for ventilation of the rear of the passenger compartment.

After a cold start in bad weather and when the heating element temperature is below 30°C, air only enters through the intensive glass heating deflectors.

This program satisfies almost all requirements for comfortable air conditioning in the passenger compartment.

For optimum operation of the automatic air distribution system, do not cover all the deflectors located on the instrument panel.



Air supply through all deflectors with automatic distribution of supplied air disabled.



Recommended for use in hot weather for ventilation and cooling of air in the lower part of the cabin.

Press this button to increase the fan speed and close the ventilation nozzles to eliminate fogging of the windshield and side windows if you do not want to press the button.

Distribution of air supplied to the feet in the front and rear of the cabin

The heated glass deflectors are only slightly open and no air reaches the flaps at the end of the center console.

Recommended for use in cold weather when ventilation is not desired and an intensive supply of hot air to the feet is required.

5 — AUC switch - automatic air recirculation system*



This system detects the maximum permissible level of pollution of the outside air with harmful substances and prevents them from entering the passenger compartment.



Pressing the switch again activates three functions:

• lEDs off - normal fresh air supply mode;
• the LED on the left lights up - the sensor measures the proportion of harmful substances in the outside air; when the content of harmful substances in the outside air is elevated, the dampers of the fresh air nozzles are automatically closed and the system operates in recirculation mode;
• the right LED lights up - recirculation mode is on.

Air recirculation systems



The air recirculation mode is recommended when the outside air is heavily polluted - the interior air is recirculated in the cabin, which prevents the penetration of polluted air from the outside.

Despite the fact that in order to improve air quality (for example, drying) the air conditioner is connected automatically, the air recirculation mode should not be turned on for a long time.

If the windows fog up from the inside in recirculation mode or AUC mode, switch to normal operation mode and press switch 9 of the air conditioner.

6 - Air conditioning switch



When the button is pressed, the air conditioner switches on in all operating modes, starting from approx. 1°C outside temperature. The air is cooled and becomes drier.



When the humidity is very high, it is recommended to dry the air by turning on the air conditioner in advance (while the evaporator is not yet covered with condensation), in this case, the glass does not fog up. At the same time, cooled air should not be supplied to the windshield, since it can fog up from the outside.

At maximum cooling capacity, the system switches automatically to air recirculation mode (with a small amount of fresh air), the glass heating nozzles are closed.

7 — Switch for maximum heating of windshield and side windows



Fogging of glass occurs due to condensation due to temperature differences or excessively high air humidity. Condensation can only be eliminated by heating the glass with a large amount of warm air.

When you press this switch, maximum heating of the windshield and side windows is carried out automatically, i.e. there is no need for any additional actions.

The maximum effect is achieved only when the engine is warm.

After this switch is unlocked, the previous operating mode is automatically restored.

Please note: when you first press the switch after starting the engine, the rear window heating turns on.





The noise after the engine is turned off is caused by the air flaps operating - they are set to their original position.

Comfortable driving conditions - thanks to the layered distribution of conditioned air: warm feet - cool head.

Driver and front passenger

The temperature of the air supplied through the deflectors on the instrument panel and front doors can be changed by rotating roller 1:

• rotate right - warmer
• left rotation - colder

Passengers in the rear seats

The air vents at the end of the centre console open and adjust as required. These vents supply only fresh air or, if the air conditioning is on, cool air.

The rear passenger compartment ventilation is automatically closed when the driver's side ventilation is switched on

• AUTO - (only in cold weather);
• air distribution only through the nozzles in the footwell.

Important recommendations for air conditioner operation:

1. The condensate formed on the evaporator is discharged under the vehicle; its quantity can be up to 2 liters per hour, depending on the air humidity.

2. As a preventative measure, the air conditioner should be turned on for a short time at least once a month (especially in the cold season). Otherwise, there is a risk of loss of elasticity of the compression shaft sealant, which may result in a leak of coolant.

3. For all air conditioner malfunctions - for example, no cold air when the system is on (temperature adjustment roller or rotary switch on driver's side in left end position) - turn it off and contact BMW service.

Microfilter

Fresh air is sucked in through a microfilter. In this case, pollen is filtered out by 100%, dust by 60%.

Filter replacement is part of the scheduled maintenance work. Reduced air exchange indicates the need for early filter replacement.

(The original text is available on the website BMWman.ru)