Comfort in the cabin when operating the car in winter is ensured by a stove in the cabin. Before the advent of the “tenth” family of models, AvtoVAZ equipped its cars with a simple mechanically controlled heating system. Starting with the VAZ-2110 model, designers revised the design of the stove and improved its control mechanism. Such modifications increase the convenience of adjusting the heating operation, and sometimes cause failure or improper functioning of the interior heating.
The design of the heating system of the VAZ-2110
The concept of interior heating on the VAZ-2110 remains the same - the air supplied to the cabin is heated by the cooling system. To do this, a radiator is installed in the cabin, under the front panel, which is included in the cooling system; heated antifreeze moves through it. The air passing through the radiator is supplied through the air intake. After heating, the air flow through the air ducts is supplied to the necessary areas - the windshield, legs, torso.
Forced air circulation is provided, which increases the efficiency of the distribution of warm flow throughout the cabin. For this purpose, the stove is equipped with a fan driven by an electric motor.
The air heating temperature is regulated by dampers. One of them allows the flow either through the radiator (for heating) or bypassing it. The damper divides the flow to obtain the desired temperature - one part of it goes through the radiator, and the second bypasses it, after which it is mixed, the degree of heating is regulated and supplied to the air ducts.
The second damper is designed to shut off the air supply to the cabin from the outside. Thanks to it, a closed air circulation mode is established.
↑ Interior ventilation
Interior ventilation is supply and exhaust: air is supplied into the cabin through holes in the windshield trim (spontaneously - when the car is moving, or forced - when the heater fan is operating) and exits through the cracks between the upholstery and the inner door panels and then through the holes in the ends of the doors. These holes have valves that allow air to come out, but prevent it from getting inside the car. This design improves the thermal insulation of the cabin.
↑ Interior heating
The air entering the cabin is heated, if necessary, by passing through the heater radiator and distributed in accordance with the position of the air flow control handle. The main part of the air is directed to the windshield and - through deflectors blocked by flaps - to the side windows and to the central part of the cabin. Air is also supplied to the feet of the driver and the passenger sitting in front through two pairs of deflectors (one pair at knee level, the other at the floor) and to the feet of rear passengers through the lining on the floor tunnel and two air ducts under the front seats.
To speed up the heating of the cabin and prevent the entry of outside air into the cabin (when crossing gas-filled, smoky, dusty sections of the road), an air recirculation system is used. When the recirculation button is pressed down (on the instrument panel), the electro-pneumatic valve opens, and under the influence of vacuum in the intake manifold, the recirculation system flap blocks the access of outside air to the car interior. Thus, the recirculation system can only operate when the engine is running. At the same time, if the fan is turned on, the air in the cabin continues to circulate, passing through the heater air ducts.
↑ Fan operating modes
The fan has three operating modes: low speed, medium and automatic speed selection (determined by the control unit). The fan electric motor is a commutator, DC, with excitation from permanent magnets. Current consumption at maximum rotation speed is 14 A.
Depending on the selected speed, the electric motor is connected to the vehicle’s on-board network directly (maximum speed) or through an additional resistor. The latter has two spirals with a resistance of 0.23 Ohm and 0.82 Ohm. If both spirals are included in the circuit, the fan rotates at low speed, if only one (0.23 Ohm) rotates at medium speed.
It is not recommended to press the fan wheel from the electric motor shaft - this can upset the balancing. The electric motor cannot be repaired (except for cleaning the commutator); if it fails, it should be replaced as an assembly with the fan wheel.
The heater radiator is installed horizontally under the instrument panel in a plastic casing and consists of two plastic tanks (the left one has a steam outlet fitting) and two rows of aluminum tubes with pressed plates. Depending on the position of the dampers, part of the intake air passes through the radiator (in the extreme positions of the dampers all the air passes or does not pass at all), while the rest of it bypasses the radiator. Unlike previous VAZ models, there is no valve to shut off the flow of coolant, so the heater radiator is always heated when the engine is running. This design ensures low inertia of the system (the set air temperature is reached faster) and the absence of leaks associated with faucet leaks.
Stove control
Previously, the dampers on VAZ were controlled mechanically - the damper was connected by a cable to a handle on the heater control unit. Additionally, the heater was equipped with a tap to shut off the supply of antifreeze to the heater radiator, which was regulated by a handle on the control unit.
Video: The stove on the VAZ 2110 does not heat up? Replacing the heater damper gearmotor
On the VAZ-2110, the shut-off valve is no longer installed, and the heater is turned off in the summer using a damper, which, when completely closed, separates the radiator from the passenger compartment. The mechanical control of the dampers was replaced with an electromechanical one - a micromotor gearbox was installed. Heating control for VAZ-2110 includes:
- controller of the automatic heater control system (AHC);
- temperature sensor;
- damper position sensor;
- micromotor gearbox
The controller is equipped with a front panel with two handles - the left one is responsible for adjusting the temperature, the right one is for operating the fan. Models of the 10th family use controllers, the difference between which comes down to the number of fan operating modes and the presence of an automatic operating mode.
Air duct modification
Damper leaking
The main reason for a poorly functioning heater is a leaky air flow distribution damper, which is originally installed on the car, causing the heat flow to dissipate in the heater itself.
In order to fix this, it is recommended to make a new damper from plastic, which will fit more tightly and ensure precise direction of air flow. Additionally, the housing is sealed to ensure higher heater efficiency.
As a rule, this helps solve the problem, but a more noticeable effect will be achieved if you additionally tune the heater as a whole.
Side windows fogging
For example, to solve the problem of side windows fogging, two options are used:
- or lay corrugations;
- or seal as tightly as possible the cracks in the panel itself, through which significant losses of air flow occur.
The corrugation helps to improve the airflow of the feet, but it will not have much effect for the airflow of the side windows. So the best way to improve side airflow is to seal all the cracks in the panel. It is especially worth paying attention to the holes for the fastening bolts - they should be sealed with tape or modelin. After this, you can additionally pay attention to the joining of the upper and lower parts of the panel.
These measures will help eliminate air loss, and all the warm air will be directed to the right place, so that the stove will begin to work noticeably more efficiently.
Principle of operation
The operating principle of such a control system is simple - the driver uses the left handle to set the desired temperature (completely cold or in the range from 16 to 28 degrees). Based on the set mode, the controller supplies power to the micromotor gearbox and it sets the dampers to the desired position.
Two-way communication is used between these elements - a position sensor is installed on the gearbox, which “informs” the controller about the opening angle. Thanks to the installed temperature sensor (located on the ceiling), the controller constantly monitors the degree of heating of the air in the cabin, based on which it adjusts the position of the damper to maintain the temperature set by the driver.
Temperature sensor VAZ 2110
Thanks to the use of automatic control system, the driver no longer needs to adjust the operation of the stove in order to maintain a comfortable temperature; he sets the temperature with a handle, and the controller does the rest. On the early VAZ-2110, the heater fan had three operating modes, the difference between which comes down to the rotation speed. Speed adjustment is carried out by installing a rheostat block in the power supply circuit of the electric motor. Then models appeared in which the fan received a 4th operating mode - automatic. When it is turned on, the fan operates under the control of the controller - the ACS regulates the rotation speed of the electric motor to adjust the temperature in the cabin.
The use of electromechanical control on the VAZ-2110 increased the convenience of controlling interior heating, but due to the more complex design, the likelihood of stove failure increased.
Stove design
This unit includes several devices. The radiator is the main element of the stove - it heats the air entering the cabin. It is located under the hood. The next component is the air distributor, equipped with special pipes that run through the cabin of the 2110.
Removing a faulty radiator, you can get to it through the hood
If we compare the “ten” with previous models, an important innovation has appeared in its heating system - an evaporator (the diagram includes it in the list). The device is installed in an air conditioning system. Not all owners know about its existence, since it rarely fails.
To control the operation of the heater, an SUAO unit is installed in the VAZ 2110 car, which is called a controller in the technical operating manual. The unit works in conjunction with a temperature sensor in the cabin; it is also called a ceiling sensor. The sensor reports the temperature to the unit, then this indicator is compared with the set temperature on the handle. If the indicators differ by more than 2°, warm or cooled air is supplied to the VAZ 2110 interior.
It’s worth taking a closer look at the handle, or more precisely at its extreme positions – MAX and MIN. If the heater knob is set to one of these indicators, heat is supplied without the operation of the temperature sensor in the cabin. The scheme includes all of the above elements.
The device of the “tens” heater includes another unit - a gearmotor, which is responsible for opening and closing the damper. The miniature electric motor performs an important task in the operation of the heating system, as evidenced by the diagram. If the gearmotor is faulty, the system will only produce cold or hot air. If the gearmotor fails when the damper is closed, the system will stop functioning. We have described the main components of the VAZ 2110 heater; the diagram contains a more detailed list.
Let us highlight the main components of the system:
- Radiator.
- Air distributor.
- SUAO block.
- Ceiling sensor.
- Lever.
- Damper.
- Gearmotor.
Radiator
In the heating system, a radiator is installed for heating, which enters the VAZ 2110. It is also called a heat exchanger. Heating is carried out by the heat of the antifreeze. This component is connected to the engine cooling system by pipes and hoses. Antifreeze constantly circulates through the heat exchanger of the stove. The damper, based on the commands of the unit, directs the incoming air to the radiator or directly into the passenger compartment. If the heater damper is in an intermediate position, then one part passes through the heat exchanger, and the second bypasses the radiator. If we compare this part of the stove with previous generations of the VAZ, it has a number of useful improvements, as the diagram demonstrates.
SUAO and ceiling sensor
The process of removing the interior temperature sensor
These components of the VAZ 2110 heater are connected and operate according to the following principle:
- The sensor determines the temperature inside the car;
- This data is sent to the SUAO block;
- The block compares the temperature with the position set on the handle of the VAZ 2110 stove;
- After comparison, the position of the damper changes or remains the same - it depends on the indicator;
- This way the temperature in the cabin is controlled;
- If the heater handle is set to MAX or MIN, then the data from the ceiling sensor is not taken into account.
All these actions are demonstrated by the diagram. The block is a set of microcircuits; the normal operation of the stove depends on its serviceability. Both the sensor and the control system can be replaced.
Damper and gearmotor
The heater gear motor changes the position of the damper, due to which air is supplied to the cabin. This component is controlled by the control system block. If the device is faulty, the damper will not move. The unit is a miniature electric motor. When it breaks, it is usually replaced, since repairing it will be problematic. This also applies to the damper. The diagram shows the connections between the gearbox and the block.
Malfunctions of the VAZ 2110 stove and their elimination
VAZ-2110 owners are faced with the problem of a non-working or malfunctioning stove. The malfunction boils down to the fact that the air does not heat up, the heater supplies hot air, or there is uneven heating - cold air goes to the windshield, but well-heated air goes to the foot area.
Why does the stove not heat well?
These symptoms occur due to a malfunction in the stove control system:
- Damage to the ACS controller.
- Malfunction of the micromotor gearbox.
- Damper deformed or jammed.
- Temperature sensor malfunction.
To identify the problem, first determine in which branch of the control system the malfunction occurred. To do this, start the engine, turn on the heater fan at maximum speed, and then turn the temperature control knob from “Min” to “Max” and listen to whether the noise changes from the fan operation. If the “controller-gearbox” branch is working properly, then the dampers move, and by changing the direction of air flow, the noise from the stove operation changes in tone.
But if the sound of operation does not change, the reason lies in the controller, gearbox or dampers.
To check the controller, replace it with a known good one and check whether the operation of the stove has changed. The next thing to check is the gear motor. The difficulty of checking is that it is located under the “jabot” on the engine side, and it is difficult to get to the gearbox. This control branch may not work due to jammed dampers.
To check the “controller-temperature sensor” branch, disconnect the wires from the sensor. Without its readings, the controller controls the damper based on the temperature set by the driver. If the problem with the operation of the stove lay in the temperature sensor, then after it is turned off, the normal functioning of the heating system will be restored, with the only difference that the automatic fan mode will stop working and the ACS will not be able to adjust the temperature of the air flow.
More often, problems arise with the controller and gearmotor. These units can be repaired, but since their price is low, it is easier to replace them with new ones.
Video: The stove on the VAZ 2110 does not heat up? Heater damper repair
Diagram and explanations for it
Below is a diagram of the parts that make up the heater system of a VAZ 2110 car.
It is worth saying that recirculation operates in the “tens” heater system, as the diagram tells us. In simple words: air circulates inside the VAZ 2110, and is not taken from the street. The main advantage is that dust and unpleasant odors do not enter the cabin from the street. There are more disadvantages to such a stove system - the glass quickly fogs up. It is recommended to open windows more often if the outside temperature allows it. Air stagnation negatively affects the health of the driver and his companions. The heater gear motor can rarely be repaired, so it should be replaced immediately.
For VAZ 2110 owners who want to modify the heater system or carry out electrical repairs, an automatic control circuit will be useful.
Other reasons
The problems associated with stove control are described above. But the stove may not work or not function efficiently enough for other reasons:
- the appearance of an air lock in the heater radiator;
- radiator clogged;
- severe wear or breakdown of the fan motor;
- malfunction of the rheostat block of the control mechanism;
- damper deformation.
These malfunctions affect the performance of the stove. On the VAZ-2110 they occur less frequently than control system breakdowns, but they should also be taken into account. To identify the reason for the cessation of normal operation of the VAZ-2110 stove, determine why this could have happened. If the fan does not work, then to fix the problem, check it, the rheostat unit and the power circuit.
The stove blows cold air - the reason lies in the stove radiator (clogged, a plug has formed in it) or in the dampers (jammed in a position where the air flow bypasses the radiator).
The stove heats poorly and it is not possible to adjust the temperature - check the functionality of the controller, micro-reducer and temperature sensor.
To identify the cause and eliminate the decrease in stove productivity, move “from simple to complex.” First, check the functionality of the system elements located in the cabin (controller, temperature sensor), and then climb under the hood to diagnose the operation of the gearbox, dampers, and fan motor.
Device diagram with all explanations
The operation diagram of the VAZ-2110 stove can tell the motorist about the presence of recirculation in it, in other words, moving air flows circulate inside the car without taking new volumes of air from the street. Thanks to this, dust and unpleasant odors, which are present in large quantities in the street air, do not enter the unit. However, it is worth noting the main drawback of such a system - the windows fog up too quickly. Experts recommend opening windows often (at a comfortable temperature outside). Otherwise, the stagnant air will negatively affect the health of everyone involved in driving this car. Due to the complexity of repair, the gearmotor must be completely replaced in case of malfunctions.
About problems with the damper
As noted a little above, two types of dampers are installed at the manufacturer: old and new. In the first case, it is plastic with a foam rubber seal. It does not shine with special quality and quickly breaks down during operation. The second type is more reliable, since the damper is metal and the seal is rubber. So, on the VAZ-2110 there are two dampers: upper and lower. The first is responsible for supplying cold air to the cabin, the second is responsible for supplying warm air. If, when switching with the handle, you hear the damper moving, but the air is cold, both blowing and blowing, then it is quite possible that the drive or the damper itself has failed. In the latter case, it is easiest to change it to a new one. In some cases, it makes sense to use glue, such as dichloroethane. However, you need to understand that for this you will have to disassemble the heater, and this is a labor-intensive task.
Using the SAUO controller, move the lever to minimum. Cold air should be blowing. If you turn it to maximum and there is no flow, this indicates a malfunction of the lower damper, which is responsible for supplying warm air. But at the same time you need to monitor whether the top one closes. If there is no cold flow, then it is closed. Another probable cause is jamming. This happens due to a banal misalignment or jamming due to rust. You can try to remove the central deflector, reach to the damper with your hand and try to move it there. This element may not fully open or close. In this case, the easiest way is to replace the damper with a new, better one.
