Re: Processing Honey
I don't have the solution you are seeking, but consider that nectar from different plants has a different timeline for crystallization. Goldenrod honey, for instance, crystallizes quite rapidly.
I'm not saying you should heat your honey more, but if you do heat beyond the hot tub temperature, consider building a box, insulated perhaps, that you can heat with lightbulb(s) inside. You can change the bulb arrangement to get a satisfactory heat level. Slow heat like this is much better than an oven, even on a low temperature. Some people use a dead refrigerator for this purpose. Aside from being free, the refrigerator is not a potential fire hazard.
USDA Zone 7A Elevation 1400 ft