What is your Hopper sitting on? If it generates heat that might be your problem. My HWS sits in the open on a shelf and has no heatiing problems.I have kept cooling fans on all my HWSs since day one just to play it safe. View attachment 113338
I also had a 722VIP before the Hopper 2k came out and I never had a problem with overheating. Sure it ran hot but it still kept going and I kept the same 722 for a number of years without any problems.