Every vehicle that uses coolant to cool the engine has a little device, called thermostat, in the cooling system. It regulates the temperature of the antifreeze, and speeds up the warming-up of the engine, maintaining an adequate heat mode.
Thermostat’s main purpose is to block the coolant stream going to the radiator, while the engine is not hot enough. When the engine is still cold the coolant doesn’t go through it. After the engine reaches the operational temperature of 95º C, the thermostat opens. By allowing the engine to warm up faster, the thermostat reduces dangerous emissions and decreases the wearing out rate of the engine.
The thermostat is located between the engine and the radiator and is usually made of brass or copper. It has a small cylinder located on the side that is near the engine. Inside that cylinder there is a ball made of artificial wax that starts to melt down when the temperature reaches 82º C. Wax is used because it can expand significantly, due to changing its physical state from solid to liquid when temperature rises. The pin is pressed in into the cylinder and connected to the valve. When the wax begins to melt, it expands and squeezes the pin out of the cylinder, opening the valve. This allows the coolant to go through the radiator. When the engine is turned off, it cools down and the wax solidifies again.
A problem with the thermostat can lead to very serious consequences. If, on one hand, it got stuck in an opened position, your car’s engine will not reach its operational temperature. If, on the other hand, the thermostat is permanently closed, it will lead to engine overheating, which can be extremely dangerous. So choose a thermostat made by a reliable company, such as Wahler. They use the best materials to minimize the risk of the thermostat getting stuck in some position. Wahler thermostats are also very precise, so the cooling system will function properly.