It's never good to go even one day during summer without air conditioning, as your home's air conditioning not only keeps the house cooler, but it also removes damaging humidity and moisture. A home interior that's too hot can mean wood and tile surfaces drying out, while having too much humidity in the space can result in the home's wood frame absorbing that moisture and developing mould. To ensure your air conditioning is always in good repair, note when it's time to call for service on the unit, and what you might be facing by way of needed repairs.
It's not cooling the home
If you've double-checked the thermostat to ensure you have the air conditioner on and not just the fan, check the outside unit to note if there is plenty of room for air circulation around it. An air conditioner works by taking air from around that housing unit, running it over a cooling coil, and then blowing it into the home. If you've stacked lawn care equipment, bikes, or other items around the air conditioner, this won't allow for that needed collection of air. Also, if you have a homemade covering of some sort for the unit, be sure it doesn't close off the unit entirely, and that there is an open side for lots of air circulation. If you've done this and the air conditioner still isn't cooling the home, it may need a recharge of refrigerant.
Squealing often means that there are bearings in the air conditioner that need replacing; these bearings allow the neck of the fan to turn properly. When bearings wear down, they rub up against each other and start to squeal.
If there is no squealing or other such noise, but the unit is simply too loud for your enjoyment when you're inside the home, ask a technician to recommend an insulating unit that you put between the air conditioner and your home, to absorb noise. A contractor might also recommend better insulation or thicker windows for that portion of the home, to block out some noise.
The temperature never feels right
If your home's air conditioner runs for much longer than it should, or it cycles on and off too quickly and the home feels very warm and then very cool, it may need a new thermostat or new wiring between the thermostat and the unit. Don't overlook this repair, as constant cycling puts early wear and tear on the unit and can cause undue damage.