Induced Draft Gas--------------------------------------------------------------------------------Available Capacities:250,000 BTU/Hr. thru 360,000 BTU/Hr.Available Warranties:3 year limited tank warranty--------------------------------------------------------------------------------Features:Small jacket diameters Short floor-to-vent heights Multiple water connections System Sentinel LED Diagnostic System Patented multiflue design Factory installed draft inducer - provides an induced draft allowing higher BTU's to be vented through a 6" vent 6" Category 1 appliance - allows for easy upgrade or retrofit of existing applications Spark-to-pilot ignition system Full port, full flow brass drain valve