I have them each on their own thermostat so they kick on independently of each other. The substrate temps I listed were on the warm side, but it’s still similar that the substrate temps are lower than the ambient temp that the Govee and the thermostat probe are reading. The hot side thermostat is set to 88 and the cool side is set to 80. I was worried since it is still pretty chilly in our house that the one wouldn’t be enough and the cold side would get too cold.