On average, window units last around 10 years. That means if your older window unit is acting up in any way or just not performing the way it used to, it's probably time to get a new one.
If you're not quite ready to buy a new window air conditioner, try cleaning it to see if you can get a few additional months or years of life out of the machine. If your window unit is six to eight years old, you could theoretically get at least two more years out of it.
You hear odd noises
It's common to hear the occasional pop or whistle as the window air conditioner turns on and off. However, squealing, grinding, scraping or regular loud bangs and pops could mean there are problems with key parts of the system, according to AC and heating company Chas Roberts. (We've also got tips on how to potentially fix a noisy AC unit here.)
The unit smells, or your home's air quality is bad
Your air conditioner shouldn't smell at all. If you notice bad smells coming from the machine as it operates, there could be a problem. A bad smell can be anything from smoky/burning smells when there's a wiring problem to musty smells that can mean mold or mildew buildup.
Mold and mildew can affect your health and a wiring problem can lead to a fire hazard. As always, reach out to a qualified repair person if you have any questions or concerns about your window air conditioner.
Your bills are going up
A noticeable increase in your electric bills during the months you use the window air conditioner (compared to previous years) is another sign it's time to replace the unit.
A common issue with older AC units is the use of the refrigerant R-22, or freon. Freon was phased out by the EPA because of its environmental impact. That means if you have a leak of refrigerant in systems that use freon, you're out of luck. The EPA set 2020 as a deadline for ending the production and import of this refrigerant.
The window air conditioner keeps breaking
Does your window air conditioner need constant maintenance or repairs just to keep running? If the costs are adding up, it might make more financial sense to put the money toward a new unit.