HOT WATER FLOOR HEATING DEVICE

PROBLEM TO BE SOLVED: To prevent reduction comfort due to rapid drop of a floor temperature in a hot water floor heating device.SOLUTION: A second operating state for supplying hot water of a first temperature while opening and closing a thermally-actuated valve, is provided between a first operating state for supplying the hot water of the first temperature to a floor heating panel while keeping open the thermally-actuated valve, and a third operating state for supplying hot water of a second temperature lower than the first temperature while opening and closing the thermally-actuated valve. Thus, heat quantity per hour, to be supplied to the floor heating panel does not rapidly decrease during the time from when the floor heating is started at the first operating state to when the third operating state is set. As a result, the heating device prevents a user from feeling as if the floor temperature has rapidly decreased to reduce comfort.