Capacitor RUN

The Air conditioner outdoor unit will not come on. Either the outdoor fan does not run, the compressor does not run, or both the fan and the compressor do not run.
You checked and reset your breaker and the outdoor unit still does not come on. You can here a little humming sound inside the unit which is the low voltage contactor humming. You pull the disconnect and disconnect the power to your outdoor air conditioning unit.

Please make sure your electrical power is off before working on any air conditioning equipment.

You take the door or cover off your outdoor unit's control box and find a bad, swollen run capacitor. EPA stopped allowing manufacturers to produce capacitors with cancer causing PCB's. Since they stopped allowing the use of PCB's the capacitors now have a shelf life.
Many times capacitor problems that will not allow the compressor or the fan to come on. Many times you can clearly see that the capacitor is bad because it is swollen or even blown apart with capacitor oil everywhere! Sometime you need a special meter to test the microfarad (MFD) rating. Most of the time you can tell they are bad because they are swollen up.
Their call dual because the capacitor starts and run both the fan and the compressor.

Problem # 1: Outdoor condensing fan motor has stopped running. This problem could be caused by a bad motor run capacitor. If your motor capacitor is not the problem, then more than likely you need a new motor. Is the fan blade tight, stiff or If the fan blade is hard to turn then you probably need a new motor.
If you are having trouble with your outdoor condensing fan motor or indoor blower motor. Check out our Motors Page:

Problem # 2: Air conditioner compressor will not start. When power is applied to the air conditioning outdoor unit the fan starts, but you hear a sound like the compressor is trying to start, for about 5 to 10 seconds. If The unit have been trying to start for some time the compressor will be VERY HOT TO TOUCH and will have to cool off before you can go much farther. The compressor is locked up and never will start HOT. What is happening is the compressor is trying to start, but because the compressor motor is locked it tries to start for a few seconds and then because of the high amperage being drawn goes off on a internal overload safety. This internal overload protects the compressor windings from overheating and burning up.
Many times we first try and get the compressor started again without having to buy a new compressor or new air conditioning system. It is called, "Super-Boost." we call it a HARD START KIT keep two or three of these on the truck.
They have saved many of my customers from having to buy new condenser unit or Refrigeration unit compressor.