I have an 18 month old Trane XB10 air conditioner. It has been professionally cleaned and serviced twice since installation, most recently about 14 days ago. It has been used for a total of perhaps 10 days.
This weekend I turned the air conditioning on for the first time since it was serviced and it did not work. On checking, I found the circuit breaker had tripped and could not be reset. I opened the back of the outside unit and was surprised to find an orange cable hanging loose, which was clearly supposed to connect to the capacitor. I have a second identical unit which I opened and confirmed that the orange wire should be connected to the capacitor, so I reconnected it in the failing unit. Unfortunately this did not resolve the problem. I was able to reset the breaker, the fan on the external unit slowly started up, but after about 1-2 minutes the breaker tripped again.
At this point I called out the same company who had performed the service. After some testing they concluded that the condensor had a ground fault and needed to be replaced. While the unit is under warranty, the labor and material to do this will run about $550.
I am having a hard time believing that the loose cable and the failure of the condensor are unrelated events. Perhaps I am just unlucky. It seems more likely to me that either a) the service engineer left the unit disconnected without saying anything because he couldnt get it to work; or b) the loose wire actually touched something that then caused the failure in the condensor.
I would really appreciate any expert views on whether a) or b) are likely or whether I am just unlucky.
Thanks in advance