Are the wires connected to your outdoor unit?

Many times we find that lawn maintenance workers have weed-wacked too close to the wires to the condensing unit and cut them. They are low voltage (24-28 volts) and can usually be repaired with wire nuts from a hardware store.
Note: Bored dogs are also responsible for chewing them as well as children tripping on them and ripping them out.

      
                                    Do you have an energy management box?

                                             

If you live in an area such as Apex which uses energy management systems then it may be shutting the power to your outdoor condensing unit off. It could be doing what it is supposed to do by shutting off some areas periodically during peak usage, but if it stays off all the time then it may be defective and need attention by the city or your power provider.
Note: We are not authorized to work on them.

Are your filters clean?

                     

Most filters are located in "filter grills" inside your house. They should be kept clean to avoid a multitude of A/C and heating problems. They should be changed about once a month

  
      Another thing to check is the breaker or fuses in your outside A/C power disconnect device located outside on the wall of your house near your A/C condensing unit.  
                       
                         

If you have a breaker that has tripped it may just need to be re-set to "ON".
Sometimes they need to be turned "OFF" first (even though they are already "ON") then back "ON".
Note: if the breaker itself is bad then it will need to be replaced by an electrician.

      Do you have a blown fuse?

If you have fuses instead of a breaker in that box outside near your outdoor A/C unit then one of them may have been blown, it may simply need to be replaced. If this is the case then you can try to resolve your problem by yourself by replacing both of them (unless you can have them tested to know which one is bad).  That way you will have replaced the bad one even though you didnt know which one it was and you will also end up having a "spare" fuse.

                         

Another thing to look for is ice forming on the bigger of those 2 copper lines
(The one with the black rubber insulation on it) going into your condensing unit.
This normally means that your system is either undercharged or has poor air flow (maybe because of those dirty filters?)

    
Turn your FAN switch to "ON"

  

If there is ice on that copper line outside then you may (or may not) also notice that there is very little air flowing through your registers. Even if there is air movement you should turn your A/C "OFF" and turn the fan switch to "ON" at your thermostat in order to thaw it out. The constant flow of room temperature air will eventually thaw the ice that is blocking the air flow.

                        

The rest of the system will always be even more frozen inside where you can't see it.
It will take at least a few hours, possibly overnight, to thaw it out enough for us to even begin to properly service it because then the ice itself will be blocking the proper air flow.