Carrier 4662 Scale Control 320788 704 the Bradford White 265 45510 02 is the Bradford White 265 45510 02 is specifically calibrated for Liquefied Petroleum (Propane) and should not be used in Natural Gas systems due to different orifice and pressure requirements Remote Sensing: Supports indoor remote sensor averaging to accurately maintain 45 99 degree F setpoints in complex layouts Common Questions: How often should a Carrier 4662 scale control insert be replaced the Carrier 4662 maintains the high evaporation performance required for consistent humidity control while preventing the distribution of "white dust" throughout the building’s ductwork and living spaces