Karpes:
I'm afraid that some of these manufacturers of the foggers aren't entirely truthful. There is a potential for heat to develop, but that is related more to the size of the container and the amount of liquid being used for the nutrient solution. I originally used a 5 gallon pail, and that only gave me enough room for 2 gallons of liquid because it's also important to have enough headspace for the fog to build up. It's easier to maintain the temperature with a larger container.
The wattage on the transformer says 29W. The output is rated at 900 mA. The heat issue I had before was because I let the fogger run constantly. I now have it on a timer: 1 hour on, 30 minutes off, and the airstones run constantly. I've used a probe type thermometer to check the temp of the seeds in the rockwool - both covered and uncovered. The temp has never exceeded the mid 70's, so everything seems to be good for me so far. There's nothing quite like a "trial by fire" and as usual, I'm leaving town in a few days. I only hope there's something I want to see when I return.
