Have you contacted the supplier? Sounds like a faulty temperature controller.
I agree.. I opened up the back and powered it own.. I have the temp set to 150F. As it heated I watched my relay controller. The light stayed red until the unit reached 150F. After that, it went off.. So Im thinking its a bad pid controller. I will try replacing it. hoping its nothing esle.Have you contacted the supplier? Sounds like a faulty temperature controller.