Yes, a portable air conditioner must be vented to the outside to function properly. Unlike window or central air conditioning systems that have a dedicated outdoor unit for ventilation, portable air conditioners have all their components housed in a single unit that needs to be vented to release hot air generated during the cooling process.
The basic working principle of an air conditioner involves extracting heat and moisture from indoor air and expelling it outside. If a portable air conditioner is not vented, the hot air produced by the cooling process will remain trapped inside the room, and the unit's cooling efficiency will be severely compromised. The unit will essentially be recirculating the same warm air without being able to adequately cool the space.
Portable air conditioners come with an exhaust hose that connects to a venting kit, usually a window vent kit or a wall vent kit. The hose is designed to direct the hot air from the air conditioner to the outdoors. Some venting kits may include an adjustable window bracket or a panel that allows you to fit the exhaust hose through the window or an opening in the wall.
It's essential to ensure that the venting setup is properly installed and secured to prevent hot air from re-entering the room and to maintain the efficiency of the portable air conditioner. If you are unable to vent the unit to the outside, an alternative option is to consider a different type of air conditioning system, such as a window air conditioner or a ductless mini-split system, that does not require external venting.