Description: The Simplicity Series of concentric venting, noncondensing, tankless water heaters are designed to make installations simple and flexible through a gas-convertible combustion system. Models come in three sizes and are designed to convert from natural gas to propane with all necessary components included. Models are available in 140,000-, 190,000-, and 199,000-Btu versions. The series also comes equipped with integrated controls for temperature adjustment and diagnostic review.