Tomorrow's Engineer: The Buck Stops Where?
Seldom will an owner now receive one, single-source, automatic control record document that reflects the entire building system diagrams and sequence of operation. The owner now has to search several closeout documents in hopes of finding the entire control system for the completed job.
One-Stop Shopping is Gone...In the years before computers, the HVAC industry relied on ATC companies who would take responsibility for the entire building control system installation. The design engineer would have a portion of the HVAC specification dedicated to these controls and would list one or more ATC contractors to competitively bid this specification requirement.
At the start of the construction phase, this contractor would submit ATC shop drawings that included a bill of materials (equipment, parts, and material data) and system flow diagrams with sequence of operation associated with the flow diagrams. It was pretty much one-stop shopping for building control systems.
With the age of computers and computer software, we have fast-forwarded to a place in the building industry where most, if not all, equipment manufacturers build equipment using integral computerized system software. This new generation of automatic controls now identified as BAS, extends far beyond the simplistic ATC strategies of the past.
In addition, and because these computerized systems are so powerful, equipment manufacturers are now able to offer equipment operating processes that far exceed the limited automatic control capabilities of bygone years. For example, today's equipment manufacturer of central AHUs can prepackage the entire central air system automatic control along with numerous energy management features, smoke control features, alarms, and monitoring and trending data for troubleshooting any problems. On the surface this all appears very innocent, but this is where owner building system control documentation begins to slip through the cracks!
... And the Documentation Needs to Catch UpBeginning with the design phase specification, the engineer may specify the central AHU sequence of operation with all its control software features furnished within the unit specification and not in the automatic control section of the specification. Quite common with rooftop unit specifications, this procedure easily applies to other air-handling equipment, boilers, and chillers. The result is that the building owner's operating data is no longer compiled with the rest of the ATC record documents, and instead it will be found in the individual equipment O&M manual.
Another specification-writing dilemma may arise when the design engineer compiles all the sequence of operations within the automatic control section of the specification but specifies in individual equipment specification sections that the associated controls shall be furnished by the equipment manufacturer and not the ATC contractor.
Using these two scenarios, the owner will find that the ATC contractor for this project will be submitting record documents that include only the sequence of operations that relate to this ATC contractor's installation.
In other words, the ATC record documents may only indicate the ATC computer shall signal that a central AHU is on or off. No other operating information will be found for this unit except a note, "refer to equipment manufacturer literature for sequence of operation." This same kind of notation may be found in the ATC record document for other equipment, too.
Is the Result a BAS ATC Manual?Analogous to the contract specification requiring the trade subcontractor (e.g., HVAC contractor) to compile and submit an O&M manual for all the equipment furnished, it seems that this same criteria should be expanded to compiling all of the building system automation and temperature controls. From the signed, owner-contractor contract point-of-view, this requirement is contractually met via a general contractor (GC) or a construction manager (CM) who has hired the trade subcontractor.
The owner does not have a legal tie with the trades (mechanical and electrical) who are hired by the GC or CM. When the building automation is separate from the HVAC contract, as is usually the case when the BAS is specified in Division 17000 of the contract specification, the same scenario occurs. In other words, it is the GC or CM who is responsible for producing a single, complete automatic control record document for turnover to the building owner at project closeout. ES