Abstract: When a service technician or the like performs maintenance of a mechanism in an indoor unit, the service technician may accidentally detach a refrigerant gas sensor and the refrigerant gas sensor may be broken. To prevent this, communication pipes (regulating members) configured to regulate the detachment of a refrigerant gas sensor are provided on the side toward which the refrigerant gas sensor is detached (front side) when a casing provided on the side toward which the refrigerant gas sensor is detached (front side) is open.

Abstract: A refrigerant gas sensor is typically attached so that an opening for introducing leaked refrigerant gas into the inside faces upward. With this arrangement, however, a small amount of a different gas such as propane and pesticide, which is sucked from the outside of an air conditioner, may be erroneously recognized as refrigerant gas. On this account, a refrigerant gas sensor 9 includes a detecting element 61 for detecting leakage of refrigerant gas and a casing member 62 provided to surround the detecting element 61. The casing member 62 has a casing opening (first opening) 62a through which the refrigerant gas is introduced into the inside of the casing member 62. The casing opening (first opening) 62a is below the detecting element 61.

Abstract: When a service technician or the like performs maintenance of a mechanism in an indoor unit, the service technician may accidentally detach a refrigerant gas sensor and the refrigerant gas sensor may be broken. To prevent this, communication pipes (regulating members) configured to regulate the detachment of a refrigerant gas sensor are provided on the side toward which the refrigerant gas sensor is detached (front side) when a casing provided on the side toward which the refrigerant gas sensor is detached (front side) is open.