Air heating apparatus

Abstract

An air heating apparatus according to the present disclosure includes an expansion tank that stores water, a water heater that receives heat from a combustion gas generated by a combustion reaction and heats the water, a heating heat exchanger that receives the water heated by the water heater and exchanges the heat with air to be discharged for heating, a fan that delivers the air to the heating heat exchanger, and a steam supply flow path that supplies steam in the expansion tank to the fan.

What is claimed is: 
     
         1 . An air heating apparatus comprising:
 an expansion tank configured to store water;   a water heater configured to receive heat from a combustion gas generated by a combustion reaction and heat the water;   a heating heat exchanger configured to receive the water heated by the water heater and exchange the heat with air to be discharged for heating;   a fan configured to deliver the air to the heating heat exchanger; and   a steam supply flow path configured to supply steam in the expansion tank to the fan.   
     
     
         2 . The air heating apparatus of  claim 1 , further comprising:
 an air supply flow path having one end connected to the expansion tank and configured to supply, to the expansion tank, a portion of the air delivered to the heating heat exchanger by the fan.   
     
     
         3 . The air heating apparatus of  claim 2 , wherein, when a direction in which the fan faces the heating heat exchanger refers to a reference direction, the other end of the air supply flow path is disposed in the heating heat exchanger in the reference direction. 
     
     
         4 . The air heating apparatus of  claim 3 , further comprising:
 a humidifying damper disposed in the air supply flow path and configured to open or close the air supply flow path.   
     
     
         5 . The air heating apparatus of  claim 4 , further comprising:
 a suction duct communicating with a room and configured to guide indoor air to the fan;   a humidity measurement device disposed in the suction duct and configured to measure a humidity of the indoor air suctioned through the fan; and   a controller configured to control an operation of the humidifying damper based on the humidity measured by the humidity measurement device.   
     
     
         6 . The air heating apparatus of  claim 1 , further comprising:
 a heating water supply flow path configured to supply external water to the expansion tank; and   a heating water supplement valve configured to open or close the heating water supply flow path.   
     
     
         7 . The air heating apparatus of  claim 6 , further comprising:
 a water level detection sensor configured to detect a water level inside the expansion tank; and   a controller configured to control an operation of the heating water supplement valve based on the water level measured by the water level detection sensor.   
     
     
         8 . The air heating apparatus of  claim 6 , further comprising:
 a drain flow path configured to discharge the water in the expansion tank to the outside,   wherein a point at which the expansion tank and the heating water supply flow path are connected is disposed below a point at which the expansion tank and the drain flow path are connected.   
     
     
         9 . The air heating apparatus of  claim 1 , further comprising:
 a circulation supply flow path formed to connect the expansion tank, the water heater, and the heating heat exchanger and configured to guide the water in the expansion tank to the heating heat exchanger via the water heater;   a circulation recovery flow path formed to connect the heating heat exchanger and the expansion tank and configured to guide the water heat-exchanged with the air to the expansion tank; and   a circulation pump disposed downstream of the expansion tank and upstream of the water heater in the circulation supply flow path and configured to pump the water in the circulation supply flow path.