How long Is An AC System Refrigeration Cycle? In general, an air conditioner runs for about 20 to 25 minutes until it reaches the desired temperature, then turns off and recycles throughout the day and night. An air conditioner should run for 10 to 15 hours a day on typical summer days.

Here are a few programming timing tips to help you create the best set-it-and-forget-it heating and cooling schedule for your home: Shut down heat or air conditioning 20 to 30 minutes before you leave home each day. Turn on heat or air conditioning 20 to 30 minutes before you come home each day.

If it's just you and your spouse, you may be fine with the temperature set at 75-77. But if you have kids and pets running around, or you're cooking and using your oven, these things can all raise the indoor temperature noticeably. So, you might find a temperature setting in the 72-74 range more comfortable.

So, it can be frustrating when the AC is not cooling below 75 degrees, even if it has been running for hours. Many factors can cause this issue, including clogged filters, refrigerant leaks and the wrong unit size.