I'm thinking about putting in a NG ventless wall heater in my insulated pole barn office with ceiling fan and turn it into a big kiln. What I found is that the ventless wall heaters max out at 118F.. Is this too much colder than ideal parameters resulting in a mold mess of a room or will a few degrees probably not matter? Or is there something additional that could help? Is the mold graph linear that it keeps growing faster until a certain temperature or is it like a bell curve that by 118 its back down to growing very slowly like it would at say 40F?