Bryan Indirect Water Heaters are now available in sizes to 8,000,000 Btu/hr with water heating capacities to 16,000 gallons per hour (at 60 degrees temperature rise).
tekmar Control Systems' Boiler Control 265 is designed to operate up to three modulating boilers to provide Outdoor Reset and Setpoint operation, or two modulating boilers to provide Outdoor Reset and domestic hot water operation.