A window AC or portable Window air conditioner can run 24 hours a day, 7 days a week without shortening its average lifespan. Running continuously will not cause overheating, excessive wear and tear to the unit, or any other damage that will shorten its life.
Indefinitely. It isn’t running that causes the most damage – it is turning on and off. As one HVAC technician put it, when an air conditioner is properly sized, “we want the condensing unit to run all the time, a hundred percent of the time with no cycling [off and back on].”
Manufacturers’ warranties are based on a consideration of the number of times the unit starts rather than on how long the unit runs. In fact, if you keep the unit well maintained, you can expect to see a lifespan of up to 50,000 hours of use.
Is it Better to Run the AC Continuously or in Intervals?It is better to leave the air conditioner running continuously. When an air conditioner runs with frequent cycles or is turned off and on repeatedly, it creates wear and tear to the compressor and will shorten the life of the unit.
Air conditioners that run on short cycles because they are oversized for the application, which means they start and stop frequently, will not last as long as units that run for long periods.