... water output: 5 L/min, 6 L/min, 7 L/min, 8 L/min, 9 L/min, 10 L/min, 12L/min, 16L/min, 20L/min (25 centigrade temperature rising); Gas ... power systems for choice Water-gas linked automatic control, easy operation; Model of Ignition Methods: Impulse Automatic Ignition; Gas Exhaust Type: Flue duct type; Summer & winter switch ...