If your air conditioner is not working, the problem can often be pinpointed to the HVAC compressor. This is not necessarily a death sentence for your HVAC unit. Many small, inexpensive and easily replaceable parts are prone to breaking down. Other times, your HVAC may simply need a thorough cleaning. The problem is often simple enough to be repaired by an average homeowner. Walking through these simple steps will help you determine what to do when your HVAC compressor won’t turn on, and decide whether or not you need to bring in the assistance of a certified HVAC technician.