Technology Awards
Last modified on 2010-02-04 15:07:50 GMT. 0 comments. Top.
By the time this post is published another ASHRAE conference will be behind us. I hope many of you were able to attend the show and take in some of the technical sessions and events. Overall, the Orlando host committee did an excellent job and we thank them for their dedicated efforts and valuable time.
This month’s Dewpoint articles focus on ASHRAE 189.1 and a discussion on water cooled chillers. The purpose of ASHRAE Standard 189.1 is to provide the minimum design requirements for high performance green buildings excluding low rise residential buildings. Cameron discusses some differences between open and hermetic drive water cooled chillers. Be sure to catch both these articles.
Technology Awards
ASHRAE technology awards recognize successful applications of innovative design which incorporate ASHRAE standards for effective energy management, indoor air quality and good mechanical design. The purpose is to recognize members who design and conceive innovative technological concepts that are proven through actual operation.
This is our opportunity to show this industry what we have accomplished and show off our innovative approach. If you have a project you would like to highlight please email me and I will follow up with you for the details of the project. Be sure to email me at john.s.davant@jci.com or phone me at 407-212-1293. I will be following up in the next couple of weeks in order to submit some of our projects.
The New ASHRAE Standard 189.1-2009
Last modified on 2010-02-04 15:05:35 GMT. 0 comments. Top.
By: John Fabian
Standard 189.1 was written in conjunction with the U.S. Green Building Council (USGBC) and Illuminating Engineering Society (IES). Its purpose is to create a standard that provides the minimum requirements for sustainable or green buildings. This Standard applies to all building types excluding low-rise residential, similar to Standard 90.1. Although one of the goals of Standard 189.1 is to reduce building energy consumption over Standard 90.1-2007, the Standard addresses other aspects such as site sustainability, water efficiency, occupant comfort, environmental impact, materials and resources. This Standard is not a rating system but instead written such that it may be adopted by organizations like government, universities or corporations. It is also hoped to be integrated into green building rating systems and serve as a prerequisite or compliance requirement, such as the ASHRAE Advanced Energy Design Guides (AEDG). For more information, visit http://www.ashrae.org/greenstandard.
Water Cooled Chillers – Open or Hermetic Drive
Last modified on 2010-02-04 15:06:27 GMT. 0 comments. Top.
By: Cameron Sherwood
There are two options for motors for water cooled chillers, Open Drive and Hermetic Drive. An open drive has an electric motor that is air cooled by the ambient air. A hermetic drive has an electric motor that is hermetically sealed and cooled with refrigerant. With having experience repairing and maintaining both open drive and hermetic drive machines, each arrangement has its advantages and disadvantages.
Open drive water cooled chillers have the possibility to be driven by other means such as steam turbine, gas motor, or gas turbine, etc. These machines can be converted to alternative refrigerants; the motors do not rely on refrigerant for cooling. Open drive electrical motors can have electrical power diversity, capable of handling high voltages, which will reduce a facilities transformer needs. The electrical motor will have more windings, though, due to higher operating temperatures thus adding motor heat to the space. Repairs can be made to the electrical motor since the motor is accessible. There is a mechanical seal for the compressor shaft that connects to the motor shaft, this mechanical seal will leak in due time. This, as we have all experienced, is in line with the old quote, “More moving parts and more points of connections creates the possibility of more probable failures in time.”
Hermetic drive chillers have electrical motors that are cooled with refrigerant; this allows for reduced motor winding and minimal heat dissipated to the space. The electrical motor heat will be transferred from the refrigerant to the condenser water. Hermetic drive chillers do not have shaft coupling of the motor to the compressor or mechanical seal, which creates a lesser chance for failure. These chillers have placement versatility, i.e. they can be placed outdoors, because the motor is sealed and not cooled by ambient temperatures.
