fixture unit


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fixture unit

A measure of the probable discharge into the drainage system by various types of plumbing fixtures; expressed in units of cubic volume per minute; the value for a particular fixture depends on: its volume rate of drainage discharge; the time duration of a single drainage operation; and the average time between successive operations.
References in periodicals archive ?
The fixture unit method of sizing is particularly intended for sizing of instantaneous or semi-instantaneous water heating systems, i.e., systems that have minimal storage.
Table 16 of ASHRAE Handbook--HVAC Applications, Chapter 50, Service Water Heating (ASHRAE 2015) is used to determine appropriate fixture unit diversified flow rates to use for various hot-water using fixtures and appliances.
Remember, however, that the fixture unit approach in the handbook does not include an explanation of how to include dishwashing equipment in a hotel application, nor any mention of laundry loads, so we cannot use this method to design for those types of systems.
Note, however, that because number of fixture units for the dishwasher is given per person rather than per dishwasher, and no guidance is given on how to estimate number of people, we cannot estimate the number of fixture units to associate with the dishwasher at the example hotel, so somehow information on dishwasher hot-water use must be added.
(2000) used a neural network approach to conceptually design complete fixture units. Kang et al.