Nippon Thermostat group companies have an extensive lineup of automotive thermo devices such as thermostat that control the temperature of engine coolant and others that control the temperature of oil and air. Such high potentiality is verified in races and rallies as well and is recognized the world over. Notably, Nippon Thermostat boasts the top share in the Japanese market and has been highly rated for performance and reliability.

To maintain engines at an appropriate temperature is an indispensable element to display the full capacity of the engine and is a critical technology impacting environmental load reduction and fuel efficiency improvement. In addition, amidst advancing functionality and complexity of engine control, we are proactively addressing new product creations that respond to such advancements and simultaneously constantly challenging proposal-type developments through combining with peripheral parts and adopting experimental and analysis equipment from the perspective of the system overall.

Inlet IntegratedThermostat


Thermostats control the temperature of engine coolant. This is one of the most important parts to constantly maintain the engine at the temperature at which the engine can display its optimal performance. Thermostats determine the engine performance as well as the environmental load that results from fuel consumption and exhaust gas, and in the end impact the overall performance of the vehicle. Thermostats for which we hold the top share in Japan can very well be said to be a product that is the “face” of Nippon Thermostat.

Our Products

Sports Thermostat

NTCL Low Temp. Thermostats are used in a wide range of motorsports, including Le Mans and the WRC, where they have proven their operating performance and durability. This is because they are based on NTCL thermostats, which are used in more than 50% of cars produced in Japan. NTCL has complete confidence in the quality and reliability of its thermostats. Even if it is not an NTCL Low Temp. Thermostat, your vehicle probably already has an NTCL thermostat on board.

One absolute difference between NTCL Low Temp. Thermostats and those from other manufacturers is the presence of a function for precise control of flow when the valve is opened. Since an ordinary thermostat allows a great volume of coolant to flow through when the valve is opened, hunting (dramatic changes in water temperature) can result. However, NTCL Low Temp. Thermostats can control flow precisely when opening the valve (to ensure that coolant flows through a little bit at a time instead of in one great gush), making it possible to restrain hunting. This function, patented in Japan, the United States and Europe, is added to the main valve.