Complexity
LiftNot marked
Rice. 12.1. Diagram of air flow in the ventilation, heating and air conditioning system: 1 – windshield blower deflectors; 2 – air flow distribution flaps to the windshield deflectors and to the instrument panel deflectors; 3 – instrument panel deflectors; 4 – air ducts for heating the driver’s and passengers’ foot area; 5 – damper for the distribution of air flows to the instrument panel deflectors and to the heating air ducts for the driver’s and passengers’ footwells; 6 – heater radiator; 7 – salon air filter; 8 – damper of the recirculation system; 9 – air supply box; 10 – air intake in the car interior; 11 – fan impeller; 12 – fan electric motor; 13 – air conditioner evaporator; 14 – drainage hole for draining condensate; 15 – temperature regulator damper; 16 – body of the heating and air conditioning system unit.
Rice. 12.2. Schematic diagram of the movement of refrigerant in the air conditioning system: 1 – combined pressure sensor; 2 – pipeline section high pressure; 3 – receiver-dryer; 4 – service valve of the high pressure line; 5 – condenser (air conditioner radiator); 6 – fan of the condenser and radiator of the cooling system; 7 – air conditioning compressor; 8 – pipeline section low pressure; 9 – service valve of the low pressure line; 10 – heater fan; 11 – evaporator; 12 – thermostatic valve.
The heating (air conditioning) and ventilation system is a single complex that provides the most comfortable conditions in the car interior, regardless of weather conditions and driving mode. The system includes a heater (increases the air temperature in any mode of operation of the system), an air conditioner (reduces the temperature and humidity of the air), a fan and air ducts with a filter (provide air exchange in the cabin, clean the air from dust), as well as a control unit (controls all elements systems for obtaining specified comfort parameters).
Note.
An air conditioning system is installed on part of the vehicle exhaust.
Outside air can enter the cabin through the door windows when the windows are down and the air blower located in front of the windshield. Air from the air blower can enter the vehicle interior through the windshield blower nozzles, side and center nozzles, as well as through the lower nozzles of the heater housing.
The heating and ventilation system of the cabin is controlled independently from the air conditioning system when performing the function of heating and ventilating the cabin, removing frost and condensed moisture from the windshield, as well as blowing the door glass. At the same time, the main elements of the heater also work when the air conditioner is turned on. The heater and air conditioner evaporator units are made in one unit.
To clean the air supplied to the cabin from dust contained in the street air, a filter is installed in the heater unit.
The car is equipped with a liquid-type heater. It is connected to the engine cooling system by two hoses passing through engine compartment.
The main components of the heater (Fig. 12.1): – heat exchanger 6 (radiator), designed to heat the air entering the cabin with the heat of the engine cooling liquid; – fan 11 s electric drive 12 (air blower), providing a controlled supply of outside air to the heater and air conditioner dampers; – damper 15 of the air temperature regulator coming from the heater into the passenger compartment; the amount of air passing through the heat exchanger of the heater and the outside air passing bypassing the heat exchanger depends on changes in its position; – dampers 2 for the distribution of air coming from the heater through the air ducts into the passenger compartment or for blowing the windshield.
In Fig. Figure 1.7 shows the panel of the control unit for heating (air conditioning) and ventilation of the car interior, installed on the instrument panel console.
Switch 18 (see Fig. 1.7) for the intensity of air supply to the cabin operates regardless of the position of the air distribution and temperature controls and controls the fan speed by changing the voltage in the electric motor power supply circuit.
The air flow distribution regulator 16 and the temperature regulator 27 control the heater dampers using cable drives.
The air conditioning system is controlled through controls located on a panel common to the heater.
By car Chery Tiggo A compressor-type air conditioning system is installed (Fig. 12.2).
Compressor mounted on the engine using a special mounting bracket and driven by a poly-V-belt that drives auxiliary units.
Axial piston compressor with variable capacity. The compressor shaft is mounted in an aluminum housing on two needle bearings and sealed on the drive pulley side with an oil seal. The compressor has seven pistons with Teflon sealing rings. Reed type valves. The capacity regulator is built into the compressor housing.
The drive pulley is installed on a double row ball bearing and when the engine is running it rotates constantly. When the air conditioner is turned on, the torque from the pulley to the compressor shaft is transmitted through friction clutch With electromagnetic drive. The compressor circulates the refrigerant through the system and creates the pressure necessary to force the refrigerant through the expansion valve opening.
Helpful advice.
If the system is working properly, when the air conditioner is turned on, a click is heard - this clutch, under the action of an electromagnet, engages with the drive pulley, and the compressor rotor begins to rotate.
But during operation of the air conditioner, the following compressor malfunctions may occur.
1. If, when the air conditioner is turned off, the clutch makes noise during rotation. extraneous sounds, it gets hot or there is a burning smell, then its bearing has probably begun to deteriorate. In this case, the bearing must be replaced. In some advanced cases, it may be necessary to replace the compressor clutch or its components.
2. If you don’t hear a clicking sound after turning on the air conditioner, then perhaps: – there is a refrigerant leak, and electrical diagram control blocks the start of the compressor; – the pressure sensor in the system has failed; – the electrical control circuit is broken; – the coil burned out electromagnetic coupling; – the engine control unit has blocked the compressor from turning on for some reason.
3. If the clutch rotates easily and freely, but when you turn on the air conditioner, you can clearly hear extraneous noise or even the engine stalls, then most likely the compressor is jammed.
The internal pumping part of the compressor cannot be repaired; the compressor will have to be replaced.
4. And the last, most insidious option. There is a click, the clutch easily rotates the compressor shaft, but there is no coolness in the cabin. In this case, perhaps the compressor is only pretending to work, but in fact it is not pumping anything.
Only an experienced specialist with control and diagnostic equipment can establish the truth. If your compressor has been diagnosed with “no compression”, then you should be sure that a good specialist has identified the problem. If in doubt, you can run the diagnostics again and make sure that the costs of purchasing and replacing the compressor are truly unavoidable.
The exact cause of the malfunction can only be determined by full diagnostics at a car air conditioning repair service center.
In some compressor versions, an emergency pressure relief valve can be installed on the cover 8 (see Fig. 12.4) of the reed valve block. In the event of an increase in pressure in the system due to failure of the pressure sensor or other emergency situations, when the set maximum pressure is exceeded, the valve membrane is destroyed and part of the refrigerant is released into the street.
As a rule, after this the emergency valve does not have sufficient tightness.
Therefore, after eliminating the reasons that caused the pressure increase and refrigerant discharge, the valve must be replaced.
Condenser (air conditioner radiator) multi-flow type installed in front of the radiator of the engine cooling system. The condenser honeycomb is made of flat thin-walled aluminum tubes with internal longitudinal partitions to increase rigidity and external fins to improve heat transfer. Aluminum tanks with flanges for connecting pipes.
The height of the tanks is divided into sections, therefore, passing through the condenser, the flow of refrigerant changes direction several times.
In the condenser, the vapors of the refrigerant compressed by the compressor are condensed and the heat released is released into the surrounding air.
When the air conditioner is turned on, the engine control unit turns on the power supply circuit for the electric engine cooling radiator fan. This improves heat exchange in the condenser and reduces pressure in the air conditioning system.
Helpful advice.
At least once a year, preferably before the start of summer operation, wash the fins A of the condenser honeycomb from adhering dirt, dust and de-icing agents B. This will improve heat transfer, reduce pressure in the system and increase the service life of system elements.
Do not use high-pressure water jets to clean the condenser. This may cause damage to the B thin-walled fin plates.
Even with regular cleaning, the need to replace the condenser arises much more often than we would like. The fact is that it is the first to absorb the flow of deicing agents, dirt and pebbles from the road. And the walls of the tubes are thin In most cases, the condenser is damaged by corrosion in the third or fourth year of operation.
If the seal of the condenser is compromised as a result of corrosion, it will be more expensive to repair it. Even if an argon welder manages to patch the hole, a leak may soon appear in another place. By the way, the pressure in the system on hot days can reach 25–28 bar.
In addition, the complex structure of the condenser tube should be taken into account: along it it is divided by partitions into channels, so there is a high probability that after welding some of the channels will be blocked. Accordingly, the dissipated power will drop and the performance of the air conditioner will deteriorate, especially in traffic jams and in hot weather.
After each experiment with patching the condenser, you will need to pay for removal and installation, welding of the condenser and refilling the system with refrigerant. So it is better to immediately install a new condenser. Instead of an expensive original one, it is quite possible to buy a cheaper condenser from authorized manufacturers of spare parts.
Receiver-dryer installed in the engine compartment with right side. The receiver body is non-separable, made of aluminum alloy. The pipelines are attached to the receiver body using flange connections. Inside the housing there is a filter element and a cavity filled with desiccant granules (silica gel). The liquefied refrigerant passing through the receiver is cleaned of possible impurities, dirt and moisture.
Note.
In case of repair or replacement of elements of the air conditioning system, if the system was in open state(some components were removed, pipelines were destroyed, etc.), the receiver dryer must be replaced. Without this, after charging the system, the refrigerant will not be dried and acids may form inside the system, which will destroy the air conditioner parts from the inside. When purchasing a new receiver, make sure that the connecting pipes are tightly closed technological plugs. A receiver stored without plugs is not suitable for use, even if it is brand new.
Thermostatic valve block type is located under the hood near the engine shield. Has flange connections. Having passed through the throttling hole in the valve body, the liquid refrigerant sharply reduces its pressure and begins to boil. A control element is installed in the valve body, which changes the flow area of the throttling hole depending on the pressure and temperature of the refrigerant. The control element is set at the factory and is not adjusted during operation.
Evaporator located in a common building with the interior heater. Made from flat aluminum tubes with external fins for improved heat transfer. Passing through the evaporator tubes, the boiling refrigerant actively absorbs heat from the air blowing on the outer finned surface of the tubes. The air is cooled and supplied by a fan to the vehicle interior.
An electronic thermostat sensor is attached to the evaporator. It monitors the surface temperature of the evaporator and, when it drops below the freezing point, sends a signal to the engine control unit to turn off the air conditioning compressor - the evaporator defrosts.
Note.
When the air passing through the evaporator cools, the water vapor contained in it condenses.
The condensate is drained through a drain pipe under the bottom of the car. If the ambient air humidity is high, a puddle of water may form under the vehicle. This is an indirect sign of the health of the air conditioning system.
During vehicle operation, particles of road dirt and dust settle on the outer surface of the evaporator, damp from condensation.
This layer is an excellent environment for life and rapid reproduction of putrefactive bacteria and fungal cultures. Over time, it appears in the car bad smell. It is felt especially strongly when the air conditioner is turned off and in humid weather.
To minimize the risk of this problem, when purchasing a car, it is necessary to carry out preventive treatment of the evaporator with special chemicals and regularly clean the drain tube. If the smell still appears, you should contact a specialized car air conditioning repair service to flush the evaporator. If the contamination is very severe, the evaporator will have to be replaced.
Pipelines connect all elements of the air conditioning system into a single sealed circuit. The pipelines and their mounting flanges are made of aluminum alloys.
Rice. 12.3. Design of the flexible insert hose: 1 – outer protective sheath; 2 – fabric cord of the load-bearing frame; 3 – plastic sealing layer; 4 – internal oil-resistant layer To connect mutually movable elements of the system, pipelines in individual sections have flexible inserts (Fig. 12.3) made of synthetic materials.
At junctions individual elements systems installed O-rings round section made of neoprene. During system repairs and when pipeline sections are disconnected, the O-rings must be replaced.
The pipelines also have two service valves for connecting diagnostic and filling equipment.
The valves are closed with threaded caps to protect them from dirt. The caps are marked with H and L symbols for the high and low pressure lines, respectively.
Note.
This is how the service valves for high pressure A and low pressure B are located on the pipelines.
The valves are equipped with spools, similar in design to the spools of wheel tires, but differing in size.
A special wrench is used to turn the spools inside and out.
Warning.
It is prohibited to check the presence of refrigerant in the system by pressing the service valve spools, since after such a check the valve spool may not close completely and refrigerant will leak from the system!
Pressure meter combined type installed on the high pressure pipe section in the engine compartment. It forcibly turns off the air conditioning compressor in case of depressurization of the system (no more than 1.7 bar) and an emergency increase in pressure in the system (no less than 28 bar) in order to protect the compressor from overloads. At a pressure of 18 bar, the sensor turns on the power circuit of fan 6 of the radiator of the engine cooling system, which improves heat exchange in the condenser and reduces the pressure in the air conditioning system (see Fig. 12.2).
Note.
The sensor is installed on the pipeline using a threaded fitting with a locking valve, so when replacing or checking the sensor can be unscrewed without disturbing the tightness of the system.
Warnings
When replacing the sensor, O-ring A on the threaded fitting of the pipeline should be replaced with a new one and lubricated with oil for the air conditioning system before screwing on the sensor.
Check the condition of the sealing surface on the sensor body. The surface must be clean and smooth.
If there are signs of corrosion, the sensor will have to be replaced.
Refrigerant. The system is charged with R134a refrigerant. Refrigerant added special oil for compressor lubrication. It is strictly prohibited to use other types of refrigerants and oils in the system.
Helpful advice.
The recommended oil type is indicated on a label affixed to the compressor housing.
Warning.
The air conditioning system is charged with high pressure refrigerant.
Contact of liquid refrigerant with a person’s skin causes severe frostbite, so if possible, carry out all work related to the maintenance, repair or dismantling of air conditioning system elements in specialized service centers equipped with professional technological equipment. When carrying out work on your own, take precautions. Wear safety glasses.
Notes
During operation car air conditioner From time to time situations arise when the air conditioning system requires servicing or repair. For this purpose, modern diagnostic and repair equipment is used. The most common situation is the depressurization of the system and the release of refrigerant from it.
Highly sensitive halogen leak detectors with sound indication are used to detect leaks.
In some difficult cases The method of ultraviolet diagnostics of the tightness of the car air conditioning system is used.
The method consists of introducing a special dye into the system in microdoses.
In places of microleaks, the dye, together with the refrigerant, gradually reaches the surface of the system elements.
During inspection of the system, under the influence of ultraviolet rays of a special lamp, the dye begins to glow (fluoresce)
and refrigerant leaks become visible. It should be noted that the dye does not have any negative effect on the system.
It can remain in the refrigerant and circulate through the system for as long as desired and only serve its purpose when a leak occurs.
After repairing the car air conditioner, it is necessary to evacuate and charge the system with the appropriate refrigerant (R134a). The volume of refilling the car air conditioner is individual for each car model.
For high-quality refueling car air conditioner required:
– precision pressure gauge blocks with special connecting tips;
– two-stage Vacuum pump For complete removal air and water vapor from the system;
– high-precision scales (division value up to 5 g) for dosing refrigerant.
Due to specific features repair of the air conditioning system, this section describes only work on the removal and installation of individual elements and the system control unit. Work related to filling the system with refrigerant should be carried out in specialized service centers.
The heating (conditioning) and air ventilation system operates effectively when the windows are closed and is a single complex that provides the most comfortable conditions in the car, regardless of weather conditions and temperature environment. The system includes:
- A heater that increases the air temperature in any operating mode of the system;
- Air conditioning, which reduces the temperature and humidity;
- Control unit for mixing cold and hot air to achieve the required temperature in the cabin.
Outside air can enter the cabin through the door windows when the windows are down and the air blower, the air intake of which is located in front of the windshield. Air from the air blower enters the vehicle interior through the windshield blower nozzles, side and central nozzles, as well as through the lower nozzles of the heater housing.
Fig 1: Distribution of air flows from deflectors and air ducts of the heating (air conditioning) and ventilation system of the LADA Granta interior.
The following air flow distribution elements are located in the cabin:
- front door glass blower nozzles;
- side air supply nozzles to the driver and passenger on front seat or on the glass of the front doors;
- windshield blower nozzles;
- central air supply nozzles to the cabin;
- air ducts supplying air to the feet of passengers in the rear seat;
- air ducts for supplying air to the driver's and front passenger's footwells.
LADA Granta climate system control unit
Fig 21 2 3 4 5
Fig 31
- fan operating mode switch; 2
- temperature regulator for air supplied to the cabin; 3
- block of push-button switches; 4
- regulator for the distribution of air flows supplied to the cabin; 5
- recirculation system control lever
The following switches and regulators are installed in the control units:
1) Fan operating mode switch. To increase the intensity of air supply to the passenger compartment while driving and to ensure air supply when the vehicle is stationary, use the switch handle to set one of the four operating modes of the air blower fan.
2)Air temperature regulator. To change the temperature of the air entering the cabin, rotate the temperature control knob. The blue part of the scale corresponds to the supply of the most cooled air, the red part to the supply of the most heated air. When the handle is in the middle position, air is supplied to the passenger compartment at ambient temperature. On a vehicle equipped air conditioning system also provides an automatic maintenance mode in the cabin set temperature.
3) Push-button switch block. Depending on the configuration, the block can be equipped with:
4) Regulator for distribution of air flows supplied to the cabin. To change the direction of air supply, use the control knob to select one of four options (clockwise):
- air supply to the windshield (through the windshield blower nozzles);
- air supply to the upper part of the cabin (through the side and central nozzles of the instrument panel);
- air supply to the lower part of the cabin (through the lower nozzles of the heater housing);
- air supply to the lower part of the cabin and to the windshield (through the lower nozzles of the heater housing and the windshield blower nozzles).
WARNING
- heater switch rear window. When you press the button, the rear window heater turns on and the heater on indicator on the button lights up;
NOTE
- the heated windshield switch is used to quickly remove frost and moisture from it. When you press the button, the windshield heater turns on and the heater on indicator on the button lights up. The system operates only when the engine is running.
The system turns off:
- automatically after 6 minutes;
- when you press the switch key again during heating;
- when the voltage drops in on-board network below the permissible level;
- when engine speed decreases below permissible limits;
- when the ignition is turned off;
NOTE
Interior ventilation
To ventilate the interior, set the ventilation and heating control unit controls to the following positions.Preventing glass fogging
When the air humidity is high (during heavy rain), the car windows may fog up. To prevent the windshield and front door windows from fogging up, do the following:Cleaning windows from snow and ice
To quickly clear snow and ice from the windshield and front door windows, do the following:Quick heating of the interior
To do this, do the following:WARNING
Ensuring a comfortable air temperature in the cabin
If the windows in the cabin are cleaned and the temperature has not yet reached the desired temperature, do the following:Cooling
To cool the interior air, do the following:NOTE
WARNINGS
In fact, not many drivers are familiar with this mode and know about its useful and negative sides.
Air recirculation in a car is the intake and “distillation” of air masses directly from. In this case, the air is cooled while passing through the climate control system, and after passing through it is distributed through air nozzles for supply to the cabin.
pros
Using this mode The air temperature in the cabin is lowered in a faster manner than the mode of intake of air masses from the environment. This mainly happens due to the repeated passage of air into the car, the temperature of which is already below the ambient temperature, through the air conditioning system.
With the reverse procedure - heating, everything is even simpler, since the temperature in the cabin is much higher than outside the car.
One more positive thing is the fact that the power consumption for compressor operation is significantly lower than when taken from the outside.
Recirculation is also an indispensable mode for people sensitive to road dust, pollen, unpleasant odors and other allergenic factors.
As an example, it is worth mentioning a situation that is probably familiar to any driver - this is a KAMAZ driving in front of you or any other vehicle that emits strong specific odors, recirculation in in this case- this is an excellent way out of the situation.
Minuses
The negative factors of air recirculation include one very important point– this is the absence of any air exchange. If in simple words, then you will have to breathe the same air.
With prolonged use, glass fogging is inevitable due to increased humidity in the car interior. Many solve this problem with joint and recirculation mode.
Where is the power button
The location of the recirculation button varies depending on the model of your car, but there are two generally accepted symbols (icons) that make them easy to find.
The buttons look like this:
Unfortunately, these designations are not typical for all models. For example, on VAZ cars the recirculation button looks like a circle of three lines and is located to the left of the regulator temperature regime. Or it may look like arrows arranged in a circle.
For those whose car, the question of using or not using this mode largely disappears, since it takes care of the cleanliness and temperature of the air upon itself.
The principle of recycling is applicable not only to cars, but is also actively used at home and in industrial areas.
For example, built-in hoods in the kitchen, which work on the same principle as described above, do not allow you to connect to a stationary ventilation pipe, but operate through integrated filters.
25 ..Peugeot 3008 Hybrid4 (2017). Guide - part 24
Comfort systems
Heating and ventilation
Air supply to the cabin
The air entering the cabin is filtered
and fed into it either from the outside through
located under the windshield
air intake, or is driven through
closed circle through the recycling system.
System management
Driver's choice, front and rear
passengers, air can be supplied to
salon in different ways - depending
depending on the vehicle configuration.
Temperature control system
allows you to adjust thermal comfort
in the salon at your own discretion
by mixing different
air flows.
Air distribution system
flow allows you to direct air into
various points of the cabin by combining
various controls.
Air control system
allows you to increase or decrease
speed of the fan supplying air
to the salon.
Depending on the configuration of your
car, the system can be controlled
via the menu "
Microclimate"
on touch screen, or with front panel
center console.
Air distribution throughout the cabin
Windshield blower nozzles for removal
frost or condensation.
Front side window blower nozzles for
removing frost or condensation.
Side ventilation grilles with damper and
air flow direction regulator.
Central ventilation grilles
with damper and direction regulator
air flow.
Air supply to the feet of the front passengers.
Air supply to rear legs
passengers.
To close the ventilation grilles:
F
side: move the cursor to the middle
position, then sideways, to the side
doors.
central: move the cursor to
middle position, then to the side, to
center of the instrument panel.
Comfort systems
"Stop-start"
Cabin heating systems and
air conditioning working
only when the engine is running.
To maintain a comfortable
microclimate can be temporarily
suspend the stop system
start".
Additional information
about the system "
stop-start" see in
To ensure proper operation of these systems, the following is recommended:
rules:
F
To ensure air flow is distributed evenly throughout the cabin, keep it clean.
external air intake grilles located under the windshield and not
block nozzles, ventilation grilles and air ducts, as well as exhaust
channels located in the luggage compartment.
Do not block the light sensor located on the instrument panel from light; He
works in the automatic air conditioning system.
To ensure long, trouble-free operation of your air conditioner, turn it on
at least for 5-10 minutes at least once or twice a month.
Keep it clean cabin filter and systematically replace everything
its design contains an additive with active components intended for
purifying the air and maintaining cleanliness in the cabin (the filter removes all kinds of
allergens, eliminates unpleasant odors and prevents the settling of grease stains).
air to specialists in accordance with the instructions given in the service manual.
warranty book.
If the air conditioner stops cooling the air, turn it off and contact your
PEUGEOT service network or a specialist workshop.
If towing a trailer with maximum weight uphill in high temperature
ambient air, turning off the air conditioner helps relieve the load on
When the air conditioner is running while parked
natural release occurs
water condensate draining
under the car.
If as a result of prolonged exposure to the sun
the temperature inside the car remains too
high, you can open it to
a few seconds to ventilate.
Set the air regulator to the mode
sufficient to ensure effective
interior ventilation.
The air conditioning system does not contain
chlorine-containing components representing
threat to the ozone layer of the earth's atmosphere.
Comfort systems
Air conditioning with manual settings
Rotate this knob between
blue zone (cold
air) and red (warm
air).
Temperature regulation
Distribution regulation
air in the cabin
To the windshield and side
windows.
To the central and side
ventilation grilles.
At the feet of passengers.
Click this button as many times as possible
how much does it take to choose
desired air direction.
Temperature setting.
On / Off air conditioner
Setting up air distribution
Setting the air supply to the cabin.
Air recirculation in the cabin.
Air conditioning system
works only when the engine is running.
Air flow distribution can be
change by adding appropriate
control lamps.
Comfort systems
Adjusting the air supply to the cabin
On/Off
air conditioner
Air recirculation in the cabin
The air conditioner is designed to operate at any time
time of year, and the interior windows must be closed.
With it you can:
-
V summer time lower the air temperature in the cabin,
in winter, at temperatures above 3°C, accelerate removal
condensation from glass.
Click this button to
turn on the system; wherein
her control panel will light up
lamp.
Click on the "
big
propeller" or " small
propeller"to enlarge
or reduce the air supply.
At the same time they will light up
relevant control
lamps.
Inclusion
Shutdown
The air conditioner doesn't work
if the air regulator
switched off.
To cool the atmosphere faster
in the cabin, maybe for a few seconds
turn on air recirculation.
Then turn the supply back on
outside air.
If you hold down the button
"
small propeller"until maturity
all warning lights (turn off
systems), the microclimate in the cabin is greater
will not be regulated.
However, slight air movement
throughout the cabin, provided by movement
car, will be felt.
Try not to include
long-term air recirculation is
may cause windows to fog up
and deterioration of the atmosphere in the cabin.
The supply of outside air allows
avoid condensation settling on the wind
and side windows.
Air recirculation allows
isolate the interior from the outside
unpleasant odors and smoke.
This same function helps speed up
reaching the desired temperature
air in the cabin.
Click this button again to
turn off the system; while her
warning lamp will go out.
Turning off the air conditioner may cause
associated with discomfort (increased
humidity in the cabin, condensation on the windows).
Click on this button again
while her control
the lamp will go out.
Click on this button when
this will light up her control panel
lamp.
The car heating system of many models is designed and operates on a similar principle. Understanding the principle of turning on and adjusting the speed of the interior heater fan will be very helpful when searching for a fault on your own (for example, if you have).
General air circulation diagram
Air is drawn into the car interior by a fan, which can be installed in the cabin or behind the engine shield. It is located above the electric motor. If heating is necessary, the air flow passes through the heater radiator. The heater radiator is connected to the car's cooling system, so when the engine heats up, circulating fluid from the engine cooling system heats the heater radiator honeycomb. Therefore, passing through the honeycomb, the air flow also becomes warm.
Air dampers
Redirection of air flows to regulate temperature is carried out by a special damper. Types of damper control:
- mechanical. The damper drive is connected directly to the switch in the cabin via rods and cables. In this case, the driver, by moving the regulator, manually doses the temperature of the incoming air;
- electronic. The damper is equipped with a servo drive. The electric motor changes the position of the damper, receiving commands from the control unit. This scheme is used on cars with climate control systems. The driver just needs to ask on-board computer desired temperature in the cabin, after which the electronic control unit, focusing on temperature sensors, will control the air damper servomotor.
Channels extend from the stove fan into the cabin, through which air can be supplied to Windshield, at the feet or through the central deflectors. Depending on the operating scheme, the modes can be either combined or single, when all the intake air is supplied to only one zone. Switching modes can be done mechanically or using a servo drive and a control unit. The mechanical method involves direct connection of the air dampers to the switch on the dashboard. The electric drive of the dampers allows you to control them by pressing a key, and also implement automatic control electronic unit cabin air conditioning systems. 
Recycling
In recirculation mode, the main air damper, after which the heater fan begins to take air from the passenger compartment. This mode of operation allows you to block the access of unpleasant odors and polluted air from the street if, for example, you are driving a car along a dusty gravel road.
In winter, the recirculation mode allows you to warm up the car interior faster, since not frosty air, but warm interior air passes through the heater radiator. Accordingly, in summer, recirculation makes it easier for the air conditioner to cool down.
Types of recirculation drive:
How does a stove fan work?
The car interior heating fan is a regular engine alternating current. This can be either the simplest axial fan or a diametrical version, which is most often installed on modern cars. The design of the internal part of the stove fan is no different from that of a conventional AC electric motor excited by permanent magnets.
Of greater interest to us is the operation of the electric motor on different speeds. This possibility is realized by including additional resistance in the circuit. Resistors increase resistance, which leads to a decrease in current flowing in the circuit. Consequently, the fan begins to rotate more slowly. The value of the resistor determines how much current will drop in the circuit. Last speed the fan is direct because there is no resistance included in the circuit. This allows the heater fan to remain operational even if the resistance has failed.
Connection diagram
The figure shows the simplest circuit diagram connecting the stove fan. When the positive terminal of the switch, protected by a fuse, is connected to terminal H, current flows directly to the motor, causing it to rotate at maximum speed. When the positive contact is closed to the V pin, current flows through the resistance, which reduces the fan speed. 
The electric heater motor of the VAZ 2108, 21099 models already has 3 fan speeds. When the positive terminal of the mode switch is shorted to 1 contact, 2 resistances are connected in series in the circuit, so the rotation speed of the electric motor will be minimal. When power is applied to the second contact of the mode switch, current will flow through one resistor, which will correspond to average speed rotation. Accordingly, pin 3 is designed to supply power bypassing the additional resistor and corresponds to the most fast speed rotation.
This is exactly the principle of turning on the electric heater motor on most cars. For a better understanding of the scheme, we suggest watching the video.
Automated control system
In the diagram we still see an additional resistor, only now all commands are transmitted to the electric fan not directly from the speed shift knob, but through the heating system control unit (No. 3). The block also controls solenoid valve interior recirculation and a micromotor-reducer for the damper drive. This scheme uses only one temperature sensor in the cabin, but in more advanced versions there are also intake air temperature sensors, as well as sensors that measure the temperature of the air supplied to the cabin at several points. 
