An indoor unit includes: a casing; a heat exchanger through which a flammable refrigerant flows; a fan; a detection sensor detecting a leak of the flammable refrigerant; a warning device emitting a warning about a leak of the flammable refrigerant; a control unit controlling operations of the fan and the warning device; and an operation device inputting stop commands for the fan and the warning device to the control unit based on its manual operation. Upon detection of a leak of the flammable refrigerant by the detection sensor, the control unit starts up the fan on condition that the fan is at a stop, starts up the warning device, disregards a stop command for the fan by the operation device, and permits a stop command for the warning device by the operation device. As a result, a user is enabled to arbitrarily stop a warning started based on occurrence of a refrigerant leak.