5A fuse breaking, contactor and reversing valve solenoid shorted on Carrier unit

Hi everyone, I appreciate any help you could provide, I'm going to give as much back story as possible to try and make my situation clear.

I own a home in north Florida and have been running the heat for a few months now on and off.

On Saturday morning I woke up to find that the thermostat was blank. This has happened in the past due to the condensate line filling with water and activating a float switch that shuts my system down. I found this wasn't the case, so next I checked the 5A fuse in my air handler and found it broken. I replaced the fuse, the system worked for a few minutes with the inside unit fan on, until I switched the system to heat and the fuse blew again.

I check the 24V circuit for shorts with a meter at my thermostat and found the C, O, and why wires to be short to one another. I went to the outside unit, disconnected these lines, checked the thermostat again and these wires were now open to one another. I believe this narrows my search to the outside unit.

I disconnected the contactor and reversing valve solenoid from the main circuit board, checked and found no shorts on the board. I removed the two wires from the board to the contactor and found the contactor to be short, I believe this piece is in need of replacement.

I checked the resistance of the two wires from the reversing valve solenoid and found them to be short, I believe this piece also needs replacement.

Finally I left the outside unit controls unplugged from the thermostat, and with a new fuse the unit is able to heat on EMHT.


Does it seem as though these two pieces need replacement at the same time? I am suspect because I don't know that they have anything to do with one another and I don't understand why they would both go bad at the same time. Are either of these pieces very difficult to replace, I like to think of myself as pretty handy, although that can sometimes get me into more trouble.

Thank you in advance.