I have a 2.5 ton Goodman air conditioner condensing unit. I was having a problem where it would burn up the contactor which would then eat the transformer. I had a service guy come out and said that I had a "tight compressor" which he used a two wire hard start kit to get running. It worked for three months then stopped, and while trying to start burned up yet another contactor and transformer. So, this year I ordered a 5-2-1 hard start kit (three wire kit) and installed it on the condensing (compressor) unit. Now it seems to be working beautifully. It is my guess that when the compressor is struggling to start it's sucking lots of power and overworking things which get pushed beyond their limits. Nevertheless, I have AC and hope that this solution will get me through another couple of summers before I have to replace the whole system. As a side note, in a previous house that we lived in it had a Singer brand heat pump. That sucker ran 28 years with no major repairs. At the 28+ year mark I replaced the outside condensing unit. As far as I know the air handler is still working. Why are modern HVAC units so sorry and short lived? I don't care the brand they all seem cheaply built while having a large up-front cost.