Cooling system provided with intercooler and control method thereof

A method for controlling a cooling system including an intercooler configured to heat-exchange a coolant and air and supply the heat-exchanged air to an engine, a radiator configured to cool the coolant heated in the engine through heat-exchange with air, and a low temperature radiator configured to cool the coolant of the intercooler and form a fluidically-closed circuit with the intercooler, the method comprising:

• determining whether the engine is in a warmed-up state on a basis of a coolant temperature of the engine;
• and
• when the engine is determined to be not in a warmed-up state, controlling a flow of the coolant according to a first operation mode, and
• wherein, in the first operation mode,
• the coolant heated in the engine is supplied to the intercooler to heat air and supply the same to the engine, and the coolant which has passed through the intercooler is supplied back to the engine without going through the radiator or the low temperature radiator.