... Rated input: 10KW, 12KW, 14KW, 16KW, 18KW, 20KW, 24KW, 32KW, 40KW. Rated hot water output: 5 L/min, ... operation; Model of Ignition Methods: Impulse Automatic Ignition; Gas Exhaust Type: Flue duct type; Summer & winter switch for choice; Over-heat protection ... freezing protection device; Super low water pressure starting design Gas Water Heater, Instant Tankless Water Heater, Natural Gas Water Heater