A heat accumulating unit includes an upstream heat accumulator and a downstream heat accumulator each accommodating a supercooling heat accumulating material. Each of the upstream heat accumulator and the downstream heat accumulator has a channel in which fluid flows. In heat accumulation of the supercooling heat accumulating material, the channel of the upstream heat accumulator and the channel of the downstream heat accumulator are set in a serial connection state by a serial connection pipe. In a temperature rise mode, fluid that has passed through the channel of the upstream heat accumulator flows in a bypass pipe.

Models that employ both measurable engine parameters as well as predictable engine parameters may be used to determine when a thermostat is malfunctioning before the thermostat malfunction results in an engine breakdown. Particular models may be used to provide an estimated coolant temperature and an estimated thermostat position. The estimated coolant temperature can be compared to an actual measured engine coolant temperature. The estimated thermostat position can be evaluated with respect to what the thermostat position should be given a particular engine coolant temperature. In some cases, comparison between a healthy model and a faulty model may be used to ascertain thermostat health.

Methods and systems are provided for a coolant system. In one example, a method may include diagnosing a condition of a pump of the coolant system based on a temperature change of coolant. The diagnostic may determine if the pump is stuck on or off.

A cooling circuit for a vehicle includes a single cooler, a refrigeration machine, a first heat-generating device, a second heat-generating device, a coolant pump arrangement configured to pump a coolant, a valve arrangement, and an electronic control module. The first heat-generating device requires the coolant at a first coolant temperature level. The second het-generating device requires the coolant at a second coolant temperature level. The valve arrangement is configured to supply the coolant from the first and second heat-generating devices to the refrigeration machine and/or to the single cooler. The electronic control module is designed to control a temperature of the coolant at coolant inlets of the first and second heat-generating devices by varying flow rates of the coolant through the refrigeration machine and/or the single cooler.

A control valve 8 according to the present disclosure includes a casing 21 in which an outlet for a liquid is formed and the liquid is accommodated, a rotor 22 rotatably accommodated in the casing 21 and having a communication port communicating with the outlet, and a sliding ring 131 having a sliding surface 141a sliding on an outer surface of the rotor in a state of being disposed inside the outlet and causing the outlet and the communication port to communicate with each other according to a rotation position of the rotor 22, in which a liquid holding portion for holding the liquid between the sliding surface 141a and the liquid holding portion is provided on the outer surface of the rotor 22, and the liquid holding portion has a recessed portion for accommodating the liquid.

A method for controlling heating of a hybrid vehicle is provided. The vehicle includes a duct flowing air into the indoor of the hybrid vehicle from the outside, a heater core for circulating the coolant heated from an engine inside the duct, a PTC heater heated by the power supplied from a high-voltage battery of the hybrid vehicle inside the duct, and a controller. The controller operates the engine and the PTC heater and heats the air flowing into the indoor of the hybrid vehicle through the duct. The voltage supplied to the PTC heater from a low voltage DC-DC converter (LDC) is changed based on the state of the engine and an auxiliary battery for supplying power to an electric component of the vehicle to apply power to the PTC heater.

An air release structure of an integrated flow control mechanism includes a flow control housing, a radiator nipple provided on an upper portion of the flow control housing and forming a bypass passage portion together with the flow control housing, a float provided in the bypass passage portion and an elastic member to support the float elastically and to selectively open the bypass passage portion.

A control valve includes a casing, a valve body, seal tube members, a fuel passage, and a thermostat. The casing has an inflow port and a plurality of outflow ports. The valve body is rotatably disposed inside the casing, and valve holes are formed in a circumferential wall portion. The seal tube members communicate with the outflow ports, abut an outer circumferential surface of the circumferential wall portion, and are opened and closed by corresponding valve holes. Thermostat opens and closes the fuel passage in response to a detected temperature. A communication groove is formed on an inner circumferential surface of the casing. The communication groove causes the inflow port and an upstream portion of the fuel passage to communicate with each other by partially expanding a gap between the circumferential wall portion and the casing.

An in-vehicle temperature adjustment system includes: a refrigeration circuit including an inter-medium heat exchanger and a vaporizer that vaporizes the cooling medium to achieve a refrigeration cycle by circulating a cooling medium; a thermal circuit including a heater core, the inter-medium heat exchanger, an engine thermal circuit, and a radiator to circulate the heating medium; and a controller that controls a distribution state of the heating medium. The thermal circuit includes: a first branch portion at which a coolant flowing out of the engine thermal circuit and the inter-medium heat exchanger is divided into coolants flowing into the heater core and into the radiator; a second branch portion at which a coolant flowing out of the heater core is divided into coolants flowing into the inter-medium heat exchanger and into the engine thermal circuit; a first adjustment valve and a second adjustment valve.

An engine system is provided, including an engine having a water jacket, a circulation system that circulates coolant through the water jacket, and a controller. The circulation system includes a radiator passage including a heat exchanger, a bypass passage bypassing the heat exchanger, a flow rate control device, and a thermally-actuated valve connected to the radiator passage and that opens to allow the coolant to pass through the heat exchanger. When an engine load is below a first load, the controller controls the flow rate control device to adjust the coolant flow rate flowing through the water jacket according to the load, by closing the radiator passage and adjusting the coolant flow rate flowing through the bypass passage. When the load is above the first load, the controller controls the flow rate control device so that the coolant flows through each of the radiator passage and the bypass passage.