I don't know if you want to do this, but when I first got my CHE, I let it run unregulated to see just how hot it would get. If it didn't reach the temps I wanted, that means I'd have to buy a bigger wattage bulb. After that I set it to the ideal air temperature I wanted, so around 87 degrees, and let it go for a while, adjusting as need be. Hope that helps!