Don't let a late night or weekend air conditioning problem send you into a panic, even if it occurs in the midst of a summer heat wave. The following tips can help you troubleshoot, and possibly even repair, your AC yourself. If that fails, you can call a 24-hour emergency AC repair technician to solve your problems and get you cool again.
Tip #1: Check the Breaker Box First
If the AC isn't coming on at all, the problem may be in the electrical connection. Open up the main breaker box for your home and find the switch that is routed to the AC. Central AC units are typically on their own switch, or they may even have their own breaker box. Turn the switch completely to the off position and then switch it back on. Sometimes, a switch may not appear tripped but it is, so attempt this fix even if all looks well inside the box. Your AC should switch back on if this was the problem.
Tip #2: Verify That the Thermostat Is Working Properly
Sometimes the failure is in the thermostat, not the AC unit itself. Try lowering the temperature on the thermostat 10 degrees to see if this triggers the AC to cycle back on. If so, your thermostat may need recalibrated. You can find how to do this in the thermostat's user's manual, or schedule a repair tech to come out during regular business hours. Also, make sure your thermostat doesn't run off batteries, since some aren't hard-wired into the home's power grid. If so, you may simply need to replace the batteries.
Tip #3: Inspect the Registers
Occasionally a register may be accidentally closed or blocked. If you can hear the AC cycling on, but no cold air seems to be entering the room or if the house is cooling unevenly, it's time for a thorough inspection. Begin by visually inspecting each register and clearing out anything that is blocking them. Then, feel them to see if cool air is blowing out. If only a register or two doesn't have airflow, there may be some damaged ductwork. If you can access the ducts, either via the basement or a crawlspace, you can find the damage and repair it with silver HVAC tape.
If these fixes don't get your AC running again, or if the problem is with the actual fan or motor, it's better to call in a professional repair person from a company like Elite Heating, Cooling and Plumbing instead of attempting a DIY fix.