How many thermostats does the new Jetta (model 13) have? Where are they all? (Please specify)

There is a thermostat next to the engine sewer pipe, as shown in the following figure:

A valve that controls the flow path of coolant. It is an automatic temperature regulating device, which usually includes a temperature sensing element to turn on or off the flow of air, gas or liquid through thermal expansion or contraction.

According to the temperature of cooling water, the amount of water entering the radiator is automatically adjusted, and the circulation range of water is changed, so as to adjust the cooling capacity of the cooling system and ensure the engine to work in a suitable temperature range.

The thermostat must be kept in good technical condition, otherwise it will seriously affect the normal work of the engine. If the thermostat main valve is opened too late, it will lead to overheating of the engine; If the main valve is opened too early, the engine warm-up time will be prolonged and the engine temperature will be too low.

How extended data works:

When the cooling temperature is lower than the specified value, the fine paraffin in the thermostat temperature sensor is solid, the thermostat valve closes the passage between the engine and the radiator under the action of the spring, and the cooling liquid returns to the engine through the water pump and circulates in the engine.

When the temperature of the coolant reaches the specified value, paraffin wax begins to melt, gradually becomes liquid, the volume increases, and the rubber tube is compressed and shrunk. When the rubber tube contracts, it generates upward thrust on the push rod, and the push rod generates downward reverse thrust on the valve to open the valve. At this time, the coolant returns to the engine through the radiator and thermostat valve, and then returns to the engine through the water pump for large circulation.

Thermostats are mostly arranged in the water outlet pipe of the cylinder head, which is simple in structure and easy to eliminate bubbles in the cooling system; The disadvantage is that the thermostat is often switched on and off when it works, resulting in oscillation.