The case should provide sufficient airflow watercooler or not
maybe the watercooler is defect?
system temp (mobo) should not exceed 40 celsius or suffa 
check HD temperatures too! 40C max is the ideal temp for a HDD too
I hadn't responded until now because I was waiting for the problem come back. After a week it did.
I reversed the flow on the 120mm side fan to now blow out. After three more weeks the problem with the disappearing hard drive has not returned. I think the problem may have been because I had 4 fans blowing in (2 front, 1 side, 1 rear) and only 1 blowing out (top). This caused the heat to build up inside the case. Now with 2 fans blowing out the inside temperatures (CPU, GPU & motherboard) all seem to be cooler now. For example the CPU seems to running during gameplay 45-55C while before it was 55-65C.
Don't think that the CPU should always be 40C with the water cooler. The Corsair H60 is not a high end water cooler. I realized that when I got it. I got it to keep the computer under normal conditions quiet. It does a good job of doing that.
Another thing is the game I have been running is GTA V. It stresses both the CPU and GPU more than any game I have ever had.