Save up to a third on your hot water bill with a condensing water heater

Save up to a third on your hot water bill with a gas condensing water heater.  It works by exploiting the waste heat created when burning heating fuel to boost the water heater’s efficiency.  Separate hot water systems can potentially save a lot, gas or oil.  The typical NYC multifamily building uses 40% of its heating fuel to make hot water.  More efficient hot water generation is needed in all buildings.  

http://www.energystar.gov/index.cfm?fuseaction=find_a_product.showProductGroup&pgw_code=WHC