Since I don't know if your using it as a two stage or single stage controller, (Whats the ambient temp around your ferment chamber)? I am going to guess your just looking to heat your chamber to 66F
IF that is the case, simply plug your controller into the pad, and scroll through the controllers menu until you reach the heat setting "H2" and set it for 66F with a 1-2 degree varience.
Monitor for the next couple of hours to see where the temp is consistently landing and either add or subtract a degree to the setting, if necessary, to reflect what the actual sustained temp is.