How does the car thermostat work? Your vehicle's thermostat opens to allow coolant to flow through the radiator and cool the engine down. The safety of our customers and team members is always our first priority, and we are taking steps to protect the health and well-being of our team and customers. If it is cold, the thermostat stays closed, keeping it in the engine. It then makes a few more stops along its way through the cooling system and ends up back in the engine. Simply put, it responds to temperature changes in the engine coolant. Size aside, the thermostat in your car has a vital job to perform. Here’s The Fix, Why Won't My Car Start? 318 A North El Camino Real Encinitas, CA 92024 (760) 634-1000, Ford Mustang on CW-5 Matte Grey Machined Face, Lexus GS-F Sport on CW-S5 Matte Black Machined Face, BMW 3series Sedan on CW-S5 Matte Grey Machined Face, THE NEW 2018 RANGE ROVER – TO BE REVEALED FOR THE FIRST TIME IN THE REGION AT DUBAI INTERNATIONAL MOTOR SHOW. To put it in simple words, a car thermostat works by responding to the changes in the temperature of the engine coolant. An overheated engine is hazardous to the well-being of the car as well as the driver. Share this conversation. This can confuse the system and cause it to display incorrect readings. How To Fix And Start Your Car. Make sure that you obtain the correct replacement by checking the serial number on the unit. When this happens, you’ll notice a drop in engine performance as it struggles to keep up. Similar to any water-cooled engines, the vehicle’s engine has to work within a specific temperature range. When the heat subsides, the agent shrinks, returning the valve to its usual closed position. The Thermostat in Your Car: A cars thermostat is a simple device that is basically a thermometer that is attached to a switch that turns on your heater. It does this by regulating the amount of water that goes through the radiator. While it may be small in size (fits in the palm of your hand), the job it performs is crucial for your engine to stay within a safe operating temperature. Including what it is, how it works, and how to tell if it’s not operating correctly. As the engine is started, it takes a few minutes to warm up, and during that time, the coolant is cold. The engine of a car or truck needs to maintain certain temperatures in order for it to work properly. First, start the engine and let it idle for a minute or two. And since the T-stat price is only about $8, it makes more sense to replace it than to spend hours diagnosing the problem. Anything that disrupts this balance of opening and closing of the thermostat valves can result in symptoms that indicate the need for proper servicing, replacement, or maintenance of the thermostat. The thermostat is a mainly a traditional stat set to a high temperature and when the car demands more power the ECU switches on the electric feed to the … The other side of the equation is an engine that’s overheating, which can be a severe issue. Car engines need an optimal temperature range, which is 194°F or 90°C, to function effectively. One of the main components in charge of regulating how hot or cold it gets is the thermostat. Most things get bigger when they heat up and smaller when they cool down (water is a notable exception: it expands when it heats up and when it freezes too).Mechanical thermostats use this idea (which is called thermal expansion) to switch an electric circuit on and and off.The two most common types use bimetallic strips and gas-filled … Finally, we will provide a step-by-step guide explaining how to check a car thermostat. (www.coldstar.co.uk) Any liquid-cooled car engine has a small device called the thermostat that sits between the engine and the radiator. A car engine works much the same way, averaging between 195-220°F. This expansion results in opening the primary valve, passing through which the coolant reaches the radiator and cools down, becoming ready to recirculate the engine again. Too much heat for too long, and you can end up with a cracked engine block or blown head gasket (basically the two worst-case scenarios). Once the engine reaches its operating temperature (generally about 200 degrees F, 95 degrees C), the thermostat opens. Once it leaves the engine, it goes to the radiator, where that excess heat is removed. Source | Hoikka1. It consists of a wax-filled cylinder, two valves-main and by-pass, and a spring. How Thermostats Work. A safe and smooth driving experience depends upon a well-functioning vehicle. 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