The principle of the thermostat in the car: diagram, device and recommendations

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Every day we are faced with the need to adjust the temperature of the water. For such purposes, a mixer with a thermostat was invented. Its working principle is very simple. But today we will talk about how the thermostat works in a car. This is a very important part that maintains the normal temperature range of the coolant. Water is not always used as the latter. Now this function is performed by a more technologically advanced antifreeze or antifreeze.

Mechanism device

This is a very small piece that fits in the palm of your hand. It consists of a body, a rod, inlet and outlet pipes, as well as a rubber chamber. Wax filler is used as a working substance. Yes, yes - it is on wax that the principle of operation of the VAZ thermostat and many other cars is based.

Among other things, the design also hasreturn spring, O-ring, valve disc and guide element. You can see a diagram of this mechanism in the photo above.

Functions

The thermostat (the principle of operation will be discussed later) is used to regulate the temperature of the coolant in the system. The element performs several tasks at once:

• Maintaining the desired thermal regime of the engine.
• Accelerating the warm-up of the power unit.

The principle of the thermostat

As we said earlier, it is based on a thermoelement - a wax filler. It is he who controls the movement of the valve. There is no electronics in the device of the element - everything is controlled mechanically. So, what is the principle of the thermostat?

When the engine is running, the element valve is in the closed state. Thus, the pump circulates the liquid only in a small circle, bypassing the main radiator. This ensures that the engine warms up quickly. As soon as the temperature has reached the set point (it can be 70-85 degrees, depending on the model and type of car), the substance begins to melt. The valve opens under the action of a spring. As a result, antifreeze begins to go to the radiator, which provides liquid cooling.

After the car has stopped working, the temperature of the antifreeze starts to drop. When it reaches a certain point (below 70 degrees), the valve will close. This will prepare the system for a cold start, where the engine will warm up quickly.

It is worth noting that the valve does not close and open immediately. The principle of operation of the thermostat in the car is designed in such a way that the element can only open halfway. Usually this range is 70-80 degrees. It will fully open only at temperatures above 95 degrees. In the same way, the valve closes softly.

About malfunctions

Note that this mechanism is highly reliable and malfunctions associated with the thermostat are very rare.

The first problem is the constantly open valve. In this case, the liquid will pass through the main radiator constantly, even during a cold start. The problem is fraught with a long warm-up of the car, especially in winter.

The second problem is the permanently closed thermostat. Unlike the first, this malfunction is clearly manifested both in winter and in summer. Signs of breakdown - too fast warm-up of the motor and overheating. The arrow does not stay in the green zone and begins to rapidly go into the red scale, beyond 110 degrees. Overheating is a very dangerous phenomenon for the engine. Therefore, if the car starts to boil, turn off the engine and move to the place of repair in tow (or go on your own with long pauses, controlling the gauge arrow on the instrument panel). The next problem is opening too early. This phenomenon is also equated to a malfunction and occurs most often due to marriage. The motor not only warms up to operating temperatures for a long time, but also does not reach its"green" mode. So, the arrow on the panel does not grow above 70 degrees. And constant driving on a cold engine can cause increased fuel consumption.

Cause of breakdowns, solution methods

In 99 percent, the cause of the malfunction lies in the fuser. In the first case, in the second case, the wax could be washed out due to breakdown and depressurization of the chamber (or it dried up due to time). In the third, the manufacturer simply did not report the thermoelement in full or installed a poor-quality spring. But in any case, the only way to solve the problem is to buy and install a new thermostat. The element is non-separable and changes entirely. And the cost of it is not too high to take measures for repair.

Recommendations for use

Domestic cars often have problems maintaining engine operating temperature. Moreover, this can occur even on a working thermostat. To solve this problem, experts recommend using different thermostats seasonally. For example, in winter, drive with an element at 85 degrees, and in summer - at 75. So the car will warm up faster in winter and not boil in summer. Also, you will not experience problems with a cold stove.

If you have an old-style 5-hole thermostat installed (these are carbureted VAZs, including “nines”), it should be replaced with a more productive, 6-hole one. The cost of such a mechanism is 800 rubles. As practice has shown, with it the motor quickly warms up in a 20-degree frost, it works greatstove.

How to check?

Since the principle of operation of the thermostat (including Kalina) is the same, this instruction is suitable for all cars. You can check the element in place without removing it. To do this, we warm up the car to operating temperatures, turn off and feel the pipes in the upper and lower parts of the radiator. Be careful - they can be hot (use gloves). If the arrow has reached 80-90 degrees, and one of the nozzles (or both) is cold, then the element is stuck and does not work.

You can determine the he alth of the element in more detail when removing it. To do this, it is placed in a container with water and brought to a boil. The principle of operation of the thermostat is based on the melting of wax, due to which the valve opens. This can be seen visually by placing the part in boiling water.

So, we found out the principle of the thermostat and its main malfunctions.