In the cooling system of a water-cooled engine for a vehicle, a heat exchanger is arranged for heating the interior of the vehicle using the heat extracted from the water which cools the engine. To provide rapid heating of the interior of the vehicle and preheating of the engine, a heating system is incorporated into the cooling system for selectively heating a portion of the cooling water to a desired temperature and then passing the heated water into the heat exchanger for heating the interior of the vehicle. After flowing through the heat exchanger, the heated water is passed through the water-cooled engine to preheat it.
In a vehicle heating system, heat exchange is made between a combustion gas generated by a burner of a heater and water by a heat exchanger of the heater and the hot water heated by the heat exchanger is sent into a cooling water heater unit of the vehicle for heating. The hot water for heating the vehicle can be obtained by change-over control of a change-over valve from the hot water of the heat exchanger or from the hot water of a radiator of an engine. Furthermore, the combustion gas generated by the burner is sent into an intake or exhaust pipe of the engine.
A liquidified gas fired system facilitates starting of an internal combustion engine by external heating of the engine coolant and fuel so as to allow periodic shut down in cold weather. The system includes an engine coolant heat exchanger inside a refractory lined fire-box which is heated to incandescent temperatures. Both engine coolant and liquified gas are preheated by regenerative cooling of the combustion products and an auxiliary gas heater is providded for unassisted cold starting of the system.
A heating apparatus, which is intended, particularly, for incorporation into a vehicle liquid heat exchange circuit has a control device, to which a liquid flow measuring device is connected. If the liquid flow measuring device detects that a predetermined liquid flow has been reached or exceeded, the control device of the heating apparatus can be put into operation as a function of other control variables. If, on the other hand, this predetermined liquid flow is not reached or exceeded, the control device, by its connection to the liquid flow measuring device, prevents turning on of the heating apparatus. As a result, the heating apparatus is turned on and delivers heat only if a heating requirement exists.
Coolant circuit of an internal combustion engine for a motor vehicle, which connects the internal combustion engine, a coolant/air heat exchanger for an interior space of the vehicle, and a combustion gas/coolant heat exchanger of a heater generating heat by combustion. The coolant circuit has a bypass line bypassing the internal combustion engine and a thermostat valve which regulates the return temperature in a predetermined range of adjustment by controlling coolant flow through the bypass line and/or the internal combustion engine. The thermostat valve is provided with at least two valves formed by valve seats and valve sealing elements, especially valve disks, wherein the range of adjustment of the thermostat valve (12) can be modified from the outside.
When the engine is stopped while the engine is warmed up, the cooling water in the engine stays therein without flowing out of the engine, and the cooling water in the radiator or the bypass passage is used for heating source for the heating operation. In this way, it is possible to heat the passenger compartment continuously even after the engine is stopped and to suppress the temperature of the cooling water from lowering to reduce the emission at restarting of the engine.
