Purchased in 01/08 still in warranty. Just thoroughly serviced: Burners cleaned many parts inspected. New circuit board installed and programed along with a new temperature setting remote thermostat which were all replaced under warranty. Selling it only because we went back to a tank water heater with circulating pump. This water heater will supply two small appliances at the same time with an inlet water temperature of 55 degrees for a small home. Specifications: Rated Gas Input (BTUs/Hr.) 31K-118K. Water Flow Rate: 0.92 GPM to 4.2 GPM. Gas connection 1/2″ NPT Male. Water connection 3/4″. 3″ special venting. 80% Efficiency rating. Electrical rating 120VAC/60Hz. Less than 2 Amps. A $250 3″ stainless horizontal vent kit and manuals included. Water heater was $650 new. There is an additional $5 handling.