Three BAS Design Points Essential for Sustainability

ASHRAE's BACnet protocol and a properly designed BAS can both contribute to the goal of long-term sustainability for a new or an existing facility. The three critical components are a networked controls design, remote Internet access and a commissioning process managed by facility operations.

Networked Controls Design. The BACnet protocol is used by the electrical, fire, security, lighting and other industries. Chillers, boilers, generators, lighting devices, switchgear, fire and security systems, and other equipment can now come with controls on-board. If the BAS is properly designed, the role of the controls contractor changes from "stick building" controls to networking controls devices onto the BACnet Internetwork. "Stick building" means that a device like an air-handling unit comes "brain dead" and the DDC system "brings life" to the AHU.

Through networked controls that are properly specified using MasterFormat 2004 Division 25, the facility staff can receive information about the health of HVAC, fire, lighting, electrical and other building systems. This information on faults, etc. cannot be obtained through a "stick building" approach.

Remote Internet Access to the BAS. This is critical to long-term sustainability. Here's why: Internet access will enable remote diagnosis. This reduces the time and transportation energy to drive to the building (and going through security in some cases), just to get into the building mechanical/electrical room to determine the problem and to order parts. There may be additional trips by specialized technicians to diagnose the problem. There may be delays, which in turn may reduce service levels to occupants. Having remote diagnosis increases service levels and improves warranty work orders for a BAS and equipment under warranty. Facility staff should work with IT to make this happen in a way that protects vital enterprise information from unauthorized access.

Commissioning Process by Facility Staff. Historically, commissioning has been handled by independent consultants, and the facility staff has simply inherited the system. To enhance sustainability, commissioning work should be structured to permit the facility staff to participate. Commissioning is an ideal training opportunity for facility staff. What's more, only facility staff has a vested interest in making sure that all wiring, junction boxes, etc., are properly tagged and identified on the as-builts so they can be found again. No commissioning should begin until all the documentation and as-builts are done.

Commissioning a networked controls system gives facility staff the chance to verify that a BAS is communicating with the device interface. For this to happen, the equipment supplier and BAS contractor must be on site at the same time.

Commissioning should test remote access procedures to meet IT requirements. This may require security clearances or network drops to be done ahead of time.

Finally commissioning is the ideal time to collect data for the enterprise preventive maintenance system. Most standard commissioning forms do not collect this data, so commissioning forms or the electronic data gathering process must be designed with this in mind.