I was given a electric brewing system. It is a homemade 5 gal pot with homemade controller. It has temp control , on/off power switch, power button for element and temp probe and separate temp on pot. Filled pot with water and powered up controller. Top readout was 72 bottom 250. Element started heating water. The temp that is on the pot showed water temp at 58 F. I was initially thinking top was current temp and bottom was your set point temp. The system comes from my homebrew club friend of a friend so it is a bit difficult to get back to the original owner so I am reaching out in the forum first.