Whether you have a whole-house or one-room air conditioner, don’t make it work harder than it should. Follow these tips for keeping your AC running smoothly, so your home will stay cool all season long.

Most central air conditioners have two basic parts: an outdoor unit (compressor/condenser) that sits next to your home and an indoor unit (evaporator) that’s located in a central duct near your furnace. If you have a heat pump instead of a furnace, the indoor unit will be in the air handler. Use the same maintenance steps we show here. If your furnace looks different from the one shown or you have a heat pump, use the owner’s manual to find your way around it. The basic parts will be the same.

Fix Fins in the Condenser
Realign bent or crushed fins with gentle pressure from a dinner knife. Don’t insert the knife more than 1/2 in.

Keep it Clean
Cleaning an air conditioner in the spring, before you start running it, will help it perform better through the dog days of summer. To start, vacuum the fins of your AC unit clean with a soft-bristle brush. Note: they’re fragile and can easily be bent or crushed. On many units you’ll have to unscrew and lift off a metal box to get at them. Check your owner’s manual for directions and lift off the box carefully to avoid bumping the fins. IMPORTANT NOTE: You should always keep a clear path to your AC unit, and keep the area around your it clear from debris, vegetation, etc.

Fix a Sinking Home Air Conditioner Pad
The concrete pads under home air conditioner and heat exchanger units tend to settle over the years. As long as there’s no strain on the copper coolant tubes and electrical lines, and the unit stays dry and level, it’s OK that the pad has sunk. But if it continues to sink and pulls the lines tight, or if water puddles around the unit, you’ll need to fix the sinking air conditioner pad.

Hosing Down Your AC Unit
It's perfectly fine to hose down an AC unit, and it's recommended on a regular basis. A condensers main function is to draw in air from outside. It also brings in pollen, dirt, leaves, dust and grass. You can just rinse the unit with running water, rinsing the machine from top to bottom, and it'll work.

Get a Programmable Thermostat
A programmable thermostat is a must-have in today’s state of AC technology. Programmable thermostats allow you to set temperatures for various times throughout the day and automatically lower the temperature when you most need it to help you save money and manage your cooling without constantly hovering over the dial. Installing a programmable thermostat is an easy DIY task you can complete in less than a day.

Replace the Filter
Turn off the power to the furnace at a nearby switch or at the main panel. Then pull out the furnace filter and check it for dirt buildup. Change it if necessary.

Check the Insulation
Condensation that forms on your outdoor AC lines reduces efficiency and raises your energy costs. But you can improve your unit’s efficiency by replacing insulation that’s damaged or rotted around your outdoor AC lines.

Unclog the Condensate Drain Tube
When you see water puddling around the furnace with the AC running, you have a clogged condensate drain tube. Condensation from air conditioning coils contains bacteria that can form slime and clog the condensate pan drain tube.