Engineer Building Facilities case studies
Engineer Building Facilities · Put your knowledge to work in context.
Engineer of Building Facilities is a New York City civil service title used by agencies such as the Department of Citywide Administrative Services (DCAS) to hire engineers who run the mechanical, electrical, plumbing, elevator, and life-safety systems of municipal buildings. The role is hands-on but supervisory: boiler and chiller plants, air handling, fire protection, water treatment, work-order backlogs, contractor oversight, and code compliance across a portfolio of facilities. The Engineer Building Facilities case studies are 5 cases and about 5,016 words.
1Low ΔT Syndrome in a Two-Chiller Plant on a Design Day
An 800-ton chilled water plant in a 22-story Midtown office tower has two 400-ton centrifugal chillers, constant-speed primary pumps, and a variable-speed secondary loop designed for 1,200 gpm at 44°F supply and 60°F return. On a 93°F August afternoon the BAS trend shows secondary flow at 1,150 gpm, 44°F supply, 57°F return, the lead chiller at 55% and the lag chiller at 29% with two surge alarms logged since morning.
932 words, about 5 min2Elevator Phase I Recall and Shunt-Trip Failure at the Annual Witness Test
A 1972 eight-story, 240,000 sq ft commercial building has six geared traction elevators modernized in 2016, a common machine room above the eighth floor with a dedicated quick-response sprinkler head, and a shunt-trip breaker located in the main electrical room. During the annual witness test with the Fire Department, the lobby smoke detector placed Car 2 into Phase I recall, but Car 4 continued to answer hall calls for a full minute before recalling on its own.
1,038 words, about 5 min3Shift Coverage Math and Overtime Spend in a 24/7 Central Plant
A 24/7 central plant serving a 900,000 sq ft mixed-use complex requires two engineers on duty on each of three shifts; one of the two must hold a valid high-pressure steam and refrigeration license. The plant is currently staffed by six licensed engineers and two maintenance technicians.
995 words, about 5 min4Capital Allocation and an Unbalanced Low Bid on Mandated Boiler Replacement
The coming fiscal year's capital budget is 1,600,000. Three projects compete: (a) replacement of two 1988 cast-iron boilers, engineer's estimate 840,000, which the insurance carrier has made a condition of renewal; (b) a 45,000 sq ft roof replacement, estimate 610,000, with active leaks over the server room; (c) elevator controller replacement, estimate 300,000, deferred twice.
1,033 words, about 5 min5VFD versus Sheave Change on an Oversized Constant-Volume AHU
AHU-3 serves 30,000 sq ft of open office on a constant-volume system. The supply fan is belt-driven, 30 hp, 460V three-phase, delivering a measured 20,000 cfm against 6.0 in.
1,018 words, about 5 min