Why is there a vent in the window AC? Should it be kept

window slot vent   Dan window slot

Order Casement Window - Trickle Window Slot Vent Set Inside & Out - 400mm - 3180mm²EA

The vent on a window air conditioner is an opening in the unit where outdoor air can enter the room and where indoor air can be exhausted  DO NOT FIT THE CLIPS INTO YOUR NEW VENT AND ROUTS YET! Safely remove your existing trickle vents, taking care not to damage the the new vent to

high volatility slot machines A 550mm long, 22mm wide Greenwood trickle vent Includes internal and external canopies which neatly cover routed slots to comply with building regulations  A great choice of window vents to fight condensation Adjustable trickle vents, night slot vents & rotary vents offering ventilation for double glazed windows