UL 448B:2017-12 Residential Fire Pumps Intended for One- and Two-Family Dwellings and Manufactured Homes.
1.1 These requirements cover fire pumps intended for use in water-supply systems for one- and two-family dwellings and manufactured homes.
1.1 effective December 23, 2010
1.2 The pumps covered by these requirements are intended for installation and use in accordance with the Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes, NFPA 13D.
1.2 effective December 23, 2010
2.1 Except as indicated in 2.2, a component of a product covered by this standard shall comply with the requirements for that component.
2.1 effective December 23, 2010
2.2 A component is not required to comply with a specific requirement that:
a) Involves a feature or characteristic not required in the application of the component in the product covered by this standard, or
b) Is superseded by a requirement in this standard.
2.2 effective December 23, 2010
2.3 A component shall be used in accordance with its rating established for the intended conditions of use.
2.3 effective December 23, 2010
2.4 Specific components are incomplete in construction features or restricted in performance capabilities. Such components are intended for use only under limited conditions, such as certain temperatures not exceeding specified limits, and shall be used only under those specific conditions.
3 Units of Measurement
3.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory or approximate information.
3.1 effective December 23, 2010
4 Undated References
4.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the latest edition of that code or standard.
4.1 effective December 23, 2010
5.1 For the purpose of this standard, the following definitions apply.
5.1 effective December 23, 2010
5.2 CORROSION-RESISTANT MATERIAL — A material having resistance to corrosion equivalent to or exceeding that of a brass or bronze alloy, or series 300 stainless steel.
5.2 effective December 23, 2010
5.3 PRESSURE, MAXIMUM WORKING — For performance tests specified in this standard, the maximum pressure developed at the pump discharge flange under any condition of intended use determined by the sum of the maximum net pressure developed by the pump and the allowed positive suction pressure. For production tests, this value may be lower, based on the conditions imposed by the particular installation for which the pump is constructed. The maximum positive suction pressure marked on the pump indicates the acceptability of a pump inlet pressures for an installation.
5.3 effective December 23, 2010
5.4 PRESSURE, NET (TOTAL HEAD) — The algebraic difference in psi (kPa) between pressures measured at the discharge flange and at the suction flange, corrected to the pump centerline and corrected for differences in velocity head at the points of gauge attachment.
5.4 effective December 23, 2010
5.5 PRESSURE, SHUTOFF (CHURN) — The net head developed by a pump at rated speed with no water being delivered (discharge valve closed).
5.5 effective December 23, 2010
5.5.1 PRESSURE, MAXIMUM NET — The maximum net pressure developed by the pump at rated speed which typically occurs at or near shutoff pressure.
5.5.1 added August 28, 2013
5.6 PUMP, END-SUCTION — A horizontal centrifugal pump characterized by having its suction nozzle on the pump centerline at the opposite side of the casing from the mechanical seal and having the face of the suction nozzle perpendicular to the longitudinal axis of the shaft. This type of pump is not intended to be used where a static suction lift is involved.
5.6 effective December 23, 2010
5.7 PUMP, IN-LINE — A centrifugal pump, the drive unit for which is supported solely by the pump, and that is characterized by suction and discharge connections having a common centerline that intersects the shaft axis. This type of pump is not intended to be used where a static suction lift is involved.UL 448B pdf download.