Specifications include, but are not limited to: 1 Ea. Domestic Water Heater 1 Ea. Start-up cost for water heater 1 Ea. Mixing Valve A. Water heating system will employ a heat exchanger utilizing steam to heat potable water and potable water will be circulated between this heat exchanger and a tandem storage tank. Building system cold and hot water connections will be made to the storage tank. B. The heat exchanger will be a vertical, double-wall, copper tube design utilizing counter flow paths for the potable water and the steam. The exchanger will be ASME stamped, section VIII and rated for 150 psi operating pressure at 250°F. C. At steam pressure up to 15 psi, a steam control valve will not be required at the heat exchanger inlet. At the end of a call for heat, a solenoid valve at the condensate outlet of the heat exchanger will close terminating the flow of steam. D. The heat exchanger will be mounted on a separate skid for field connection to the sidearm storage tank. Heat exchanger to tank piping will factory pre-assembled and shipped separately for field installation. All piping to and from the potable water side of the exchangers will be non-ferrous. E. Heat exchanger will include a steam trap and a condensate y-strainer. F. Potable water piping to the heat exchanger will include a bronze y-strainer with a blow down valve. G. Potable water piping will include isolation valves to allow clean in place. Dedicated clean-in-place ball valves will be provided. H. Potable water piping to the heat exchanger will include a bronze circulator properly sized for the heat transfer requirements and pressure drop through the factory pre-assembled piping