Our central air conditioner unit is over 15 years old and recently it hasn’t been working quite as reliably as we’d like. Even though I’ve been doing my best to care for my central air conditioner is appears that mine might on its way out. About once every couple of days now it simply “stops” coming on and I have to try a bunch of different things to get it working again. I was planning on getting a new central air conditioner in the next year or two anyway, but it looks like I may be doing it a little earlier than I had anticipated.

Without getting too technical I thought I’d share with you a couple steps you can try before calling in the air conditional repair (or sales) guys:

1. Make sure you’re setting the thermostat properly. Some thermostats don’t immediately turn on the unit and some have a 2 or 3 degree temperature “window” they use to gauge whether the air conditioner should switch on or not.

2. Make sure your thermostat is working well. A lot of homes have electronic thermostats these days and most run on battery power. Those batteries do have to be changed from time to time. My electronic thermostat supposedly had a low battery indicator, but I’ve found that changing the batteries before seeing the indicator has helped in the past. An electronic thermostat is just an automatic switch that basically turns your AC unit on and off at certain temperatures. If the batteries are low the switch may not be turning on or reading the air temperature properly.

3. Check your fuses. A central air conditioner may have several different fuses in the whole electrical system. First try resetting the fuse for your central air conditioner at your electrical box by turning it off and then on. For my system I have to then go to my furnace/blower and flick a second switch on and off. This switch turns off whenever I turn off the main electric to it. A third fuse is probably outside on the wall next to the air conditioner unit or on the unit itself. Unless you know what you’re doing I wouldn’t recommend trying to change out these fuses which are often not on switches from what I’ve seen.

4. Check any reset buttons. Some newer air conditioner units have reset buttons which are essentially just fuses as well.

5. Read the manual! I put this last because, let’s face it, you’ve probably lost or never had the operations manual! If you can find the operations manual to your central air conditioner unit you may want to investigate to see if there are any recommended troubleshooting suggestions.

If you’ve tried most of these and still can’t get your AC working then the problem could be less of an electrical one and more of a mechanical one. Remember: be safe! If you’re uncomfortable trying any of these steps then call a qualified air conditioner repair person!

From what I’ve seen most central air conditioners have a lifespan of about 12 - 18 years, though I once lived in a house with a little unit that was 22 years old and still running well. Though it might cost you $2,500 - $5,000 to replace it’s important to remember that a new one will be much more energy efficient than your old unit and you’ll have a little more peace of mind when you see those triple digits pop up on the weekly weather forecast!

Good luck and stay cool!