We have around 12 different models of indirect water heaters for sale. It is one of the most economical ways of getting hot water, especially if you set the heat source boiler to “cold start” mode. This water heater system possesses anode protection that keeps it safe from corrosion. There’s also a pressure and temperature relief valve (P/T valve) that protects the unit from excessive temperature and pressure. The unit also has good heat retention barrier due to CFC-free polyurethane foam insulation. Enjoy one year of manufacturer’s warranty with this ETL-listed range of indirect water heaters that you can buy online.