Interesting heater, I'll want to hear how it did for you this winter.
As far as the wireless transmitter, I have a set, and if my receiver is not VERY close to the transmitter outside, it doesn't read the info. I though the battery was dead on the transmitter, but when I moved receiver to the inside of the same wall it was on, it picked up the info. A second receiver is about 30' away through another wall, and receiver picks up both. Had a floating thermometer on both ponds, one receiver in the house, but receiver typically only picked up the info from the closest koi pond's thermometer, and then not all the time. Goldfish pond is only about 20' farther, but plants in between it and house I guess causes signal to be disturbed. In the equipment's defense, I always buy stuff on sale and cheap ... so maybe if I went with more or most expensive, they would work better. :blueflower: