For an air conditioner, a quick release mechanism to expose a filter includes a body, a front panel, and a locking mechanism. The front panel is pivotally mounted on the body. The locking mechanism has a guide member, a slider, a compressible spring as a biasing member, and a push block. The slider is slidably disposed in the guide member. The slider has a hook portion. The biasing member provides a force to the slider. The push block is held in the guide member when the push block engages the hook portion, and the push block is ejected from the guide member by the biasing member when the push block disengages from the hook portion.