Just how long can I run the Joule for? What is its duty cycle? I've had it running for 48 hours at 147°F (can you guess why?) and it seems to be doing okay. But every couple minutes, it sounds like the circulation motor slows down momentarily. I don't think I have anything else on the power-line that would interfere (like how the Joule makes the fridge lights flicker hypnotically to let you know that your slabs of bacon are becoming incredibly awesome).