This Unified Facility Criteria (UFC) provides requirements and guidance for the majority of plants that provide boilers for heating facilities and for process. These boilers are governed by ASME Boiler and Pressure Vessel Code, Section I, Rules for the Construction of Power Boilers and Section IV, Rules for the Construction of Heating Boilers. Typically, these are isolated steam plants under 1.0 bar (15 psig), central steam plants over 1.0 bar (15 psig), and isolated and central hot water heating plans. A heating plant contains one or more boilers. The plant may be an individual boiler serving a single building or a compact group of buildings, or a central plant with several boilers serving many buildings and facilities through an extensive distribution system.
The heating plant instrumentation and controls discussed are in general, for a saturated-steam power boiler heating plant. The typical saturated-steam power boiler heating plant discussed will operate at a design steam pressure greater than 1.0 bar (15 psig), with a heating capacity of greater than 422 Megajoule/h (400,000 Btu/h). Instrumentation is a rapidly changing field. The options available in choosing and designing plant instrumentation are numerous. A boiler plant includes a large number of instrument items, all of which have to be specified in the procurement of a boiler plant. This UFC does not attempt to cover all details. Rather, its purpose is to present general guidelines for selecting and designing instrumentation for boiler plants.