NSF ANSI 5 pdf free download

NSF ANSI 5 pdf free download.Water heaters, hot water supply boilers, and heat recovery equipment.
5.1.2 External surfaces shall be easily cleanable.
5.2 Equipment mounting
5.2.1 Water heaters and heat recovery equipment shall be:
— designed to be sealed to a floor, raised base. counter, or shelf, and fabricated so that seepage cannot accumulate under the unit; or
— elevated on legs to provide a minimum clearance of 6 in (153 mm) beneath the unit.
5.2.2 Necessary piping (including piping inlets and outlets), gas burner enclosures, and service connections (for water supply, electrical, steam, or gas service) may be present in the clearance space provided that there is a minimum of 4 in (102 mm) of unobstructed space beneath the unit.
NOTE — Where practical, service connections should be located so that horizontal pipes. conduits. and wires can be installed with a minimum clearance of 6 in (153 mm) above the floor.
5.3 Legs and feet
5.3.1 Legs and feet shall be fastened to the body of the machine and shaped at their floor or counter contacts to minimize the accumulation of dirt and the harborage of vermin.
5.3.2 Legs and feet shall be sufficiently rigid to support the equipment with a minimum of cross bracing.
5.3.3 If the outer dimension of a leg exceeds the outer dimension of its foot by 1/2 in (0.50 in, 13 mm) or more in the same plane, then the foot shall extend at least 1 .0 in (25 mm) below the leg at the minimum adjustment (see figure 1 a).
5.3.4 Hollow sections between leg and foot shall be closed. Legs and feet shall have no exposed threads at the maximum adjustment.
5.3.5 Gussets shall be assembled to the equipment and shall be easily cleanable and designed to prevent vermin harborage. The resultant assembly shall have no recessed areas (see figure 1 b).
5.4 Temperature regulators
Water heating equipment shall have a thermostatic control with a maximum differential of 15 °F (9 C). This ensures that the thermostat actuates at an incoming water temperature of not greater than 15 F (9 :0) below the outlet temperature.
5.5 Recirculation systems
Recirculation systems shall be designed to recirculate water through the heater and maintain the required temperature in the hot water supply line. If the recirculating system is supplied by the manufacturer, the manufacturer shall provide guidelines for acceptable method(s) of installation and recirculation.
5.6 Backflow and cross-connection protection
5.6.1 Heat recovery equipment
Heat recovery equipment shall be manufactured to prevent a cross connection with the potable water system or a backf low into the potable water system when there is a failure of a single barrier system.
5.6.2 Single wall heat exchangers
5.6.2.1 The pressure of the heat transfer medium in a single wall heat exchanger shall be less than the intended minimum operating pressure of the potable water system. Single wall heat exchangers shall have one or more devices capable of automatically maintaining the pressure of the heat transfer medium entering the unit at a level less than the pressure of the potable water exiting the unit.
5.6.2.2 Single wall heat exchangers shall have a permanently affixed label identifying the intermediate transfer media, which must be used with the unit. The intermediate transfer media shall conform to the requirements in 4.3. When intermediate transfer media is not supplied by the manufacturer, a permanently affixed label shall identify the intermediate transfer media to be used with the unit.
5.7 Louvers
5.7.1 Louvers that may be subject to overhead splashes, spills, and drips shall be of a deflecting design, or they shall be readily removable and the space immediately behind the louver easily cleanable.
5.7.2 If electrical safety requirements prohibit the use of readily removable louvers, then such louvers need only be removable.NSF ANSI 5  pdf download.