THERMOSTAT CONTROL METHOD AND THERMOSTAT ASSEMBLY OF COOLING SYSTEM FOR ENGINE

摘要

A thermostat assembly for an engine cooling system and a thermostat control method are provided to improve the heating performance by allowing cooling water to be bypassed through only an outlet port as an electronic thermostat is closed and allowing the cooling water to be supplied to a heater core when a heater control valve is opened. A thermostat assembly for an engine cooling system comprises a thermostat housing(2) and a thermostat(22). The thermostat housing includes first and second fluid chambers(6,8), a first inlet port(10), a first outlet port(14), a second outlet port(16), a second inlet port(18) and a third outlet port(20). The thermostat is provided at the third outlet port. The second outlet port is formed in the first fluid chamber. An electronic thermostat is provided at the second outlet port. A bypass fluid path(28) is formed between the first outlet port and the second inlet port. A heater control valve(30) is provided at an inlet portion of the bypass fluid path.