Abstract: According to the present invention, a catalyst combustion apparatus includes a ring-shaped catalyst body for catalytically burning the mixture of the fuel and the air, which is disposed in a combustion cylinder. In the combustion cylinder, a fuel nozzle and an inlet for the air are disposed at one end side of the catalyst body, and the premixing chamber is formed at the other end side. The fuel and the air are supplied from one end side of the catalyst body through a through-hole formed at a center portion of the catalyst body and is mixed in the premixing chamber. In the premixing chamber, a flow direction of the mixture is turned toward the catalyst body. A part of the exhaust gas is introduced into the air at one end side. In this way, it is possible to simplify and downsize the combustion apparatus, while securing the preheating effect of the air by the circulation of the exhaust gas.

Abstract: To prevent a thermal medium from assuming a superheated state and to stably supply hot air for warming in an apparatus which performs warming by a combustion heater. A hot-water recirculation path connecting a hot-water heater core, water pump, cooler for a motor for running use and an inverter device, first switching valve, and combustion heater in a closed loop is provided. A temperature sensor is disposed at an intermediate location in the hot-water recirculation path. A heat-radiating passage having a second switching valve and radiator is connected to the hot-water recirculation path. During heating operation, an ECU closes the second switching valve and switches off a radiator fan when a detected temperature of the first temperature sensor is less than a set temperature for radiating heat, and opens the second switching valve and switches off the radiator fan when the detected temperature of the first temperature sensor is the set temperature for radiating heat or more.