Navien’s NPE-S series condensing tankless water heaters supply maximum inputs from 150,000 to 199,900 Btu per hour and efficient outputs from 148,500 to 197,900 Btu per hour. Maximum flow rates are from 8.4 to 11.1 gpm. Other features include: 1/2-inch gas pipe capability up to 24 feet, 2-inch PVC venting up to 60 feet, dual stainless steel heat exchangers, field gas convertibility and the ability to cascade up to 16 units without an external control box. 949/420-0420; www.tanklessmadesimple.com.