Home / Wiring / CIT-1 What gauge wire should be used for the CIT-1? 12 AWG 3-wire jacketed cable should be used when extending over 500’ from the controller up to 2000’. 18 AWG 3-wire jacketed cable should be used up to 500’. Underfloor Heating Thermostats Heated Floors Further Questions? Installation - How far from the controller can the CIT-1 sensor be placed? - Installation of the CIT-1 Miscellaneous questions - At what temperature does the CIT-1 sensor activate? Wiring - What gauge wire should be used for the CIT-1? - Is the CIT-1 sensor high or low voltage?