Low Voltage Thermostat Terminal Designations G R Y System Switching Cool-Off Fan Switching Auto-On Automatic Changeover No Dual Transformer Compatible No Power Method Hardwired Voltage 20 to 30V AC 750mV Compatible No Mounting Horizontal or Vertical Height 5 in Width 3 1/4 in Depth 1 5/16 in Color White Control Range 50 Degrees to 90 Degrees F Features Mercury Free For Use With Conventional Cool-Only System