C.D.S. Newsletter October 2008

• Using Trane Acoustics Program (TAP) to meet LEED® for Schools EQ Prerequisite 3 and EQ Credit 9
• Recent C.D.S. Survey Results on Licensing
• Brainstorming to Improve Appendix G of ASHRAE 90.1
• Frequently Asked Support Questions
• Meet the Support Staff...Eric

Using Trane Acoustics Program (TAP) to meet LEED® for Schools EQ Prerequisite 3 and EQ Credit 9

LEED® for Schools for New Construction and Major Renovations Version 2007 contains both a prerequisite for classroom acoustics and the potential for earning up to two credits for improved acoustical design. TAP (Trane Acoustics Program) can be used to meet both the prerequisite and earn the credits.

Both the credits and the prerequisite allow compliance by following the methodology in either ANSI Standard S12.60-2002, Acoustical Performance Criteria, Design Requirements and Guidelines for Schools, or in the 2003 HVAC Applications ASHRAE Handbook, Chapter 47 on Sound and Vibration Control. TAP is a useful tool in determining the HVAC component when following either compliance path.

As outlined in LEED® EQ prerequisite 3 attaining an acoustically appropriate environment for a classroom requires controlling sound reflections, sound entering from adjacent spaces, and background sound. Sound reflections, measured by reverberation time, are controlled using sound absorbing materials on the room surfaces. Sound entering from adjacent spaces is controlled by designing the room using materials with sufficient STC (Sound Transmission Class) ratings to block the unwanted sounds.

Background sound refers to the sound in the classroom that comes from lights, plumbing, HVAC, and built-in equipment used during instruction (e.g., AV equipment). As noted in the prerequisite, “Isolating HVAC noise is probably the critical element to be considered in the design phase. Isolating HVAC noise depends on the type of mechanical equipment chosen and its location.” Modeling the background sound generated by an HVAC system is exactly what TAP is designed to do.

The equations (or algorithms) that drive TAP’s sound calculations were originally pulled from Algorithms for HVAC Acoustics, last published by ASHRAE in 1991. NEBB (National Environmental Balancing Bureau) published an updated version of the algorithms in 1994. Since 1991 ASHRAE has published updated algorithms in both the Applications Handbooks and in research papers. TAP has been periodically updated to incorporate all the changes made by ASHRAE. As a result, TAP is an excellent tool for the predicting background sound levels from HVAC equipment.

Requirements for EQ Credit 9 and EQ Prerequisite 3.
Acoustical Society of America ANSI S12.60-2002.

Recent C.D.S. Survey Results on Licensing

According to a recent survey, 25% of our customers are not aware that our software is sold with a one-year license agreement and that there is an annual renewal fee. Almost 17% are unaware of the services available to current license holders. C.D.S. would like to address this issue by highlighting key services available to current license holders.

When you license C.D.S. software annually, you are entitled to the following:

World-Class Support. The license agreement includes unlimited calls and e-mails to the C.D.S. support center. Our dedicated support specialists are available to answer your questions five days a week and are located with the applications engineering group – authors of industry-recognized educational materials and Engineers Newsletters. C.D.S.– will answer your questions promptly and provide solutions for your HVAC design.

Training Services. Our support specialists provide training six times a year in La Crosse, Wis. Training can also be arranged on-site. (Course fees do apply.) Courses cover a broad range of topics. Or custom training can be scheduled onsite to fit your particular needs.

Superior Software built on Trane expertise. C.D.S. continually updates software with the HVAC industry’s latest trends and requirements. As a licensed user, you can download software updates from the C.D.S. website throughout the year. Customers have a direct line to C.D.S. Support to provide program feedback or recommendations for product enhancements.

To find out the full range of services available to C.D.S. license holders, contact the C.D.S. Support Center at 608-787-3926 or email cdshelp@trane.com.

Brainstorming to Improve Appendix G of ASHRAE 90.1

When: Wednesday, November 19, 2008

Where: GreenBuild, Boston, MA - Room 160ABC

Time: noon-1:00PM

If you have used ASHRAE Appendix G Performance Rating Method to qualify for LEED-NC EA Credit 1 points, you probably have ideas on how it can be improved. This session is your opportunity to contribute those ideas on how to improve Appendix G. The 90.1 Energy Cost Budget subcommittee is inviting you to this special meeting at GreenBuild to gather improvement ideas. We will start with brainstorming a list of possible Appendix G changes and then vote to identify the highest priority improvements. We want to improve Appendix G based on ideas from people who regularly use Appendix G. For further questions or details email the 90.1 Energy Cost Budget subcommittee at 901ecb@lists.onebuilding.org.

For more information visit lists.onebuilding.org/listinfo.cgi/901ecb-onebuilding.org

Frequently Asked Questions

Where do I input a safety factor in TRACE?

TRACE does not have any one single entry dedicated to providing a factor of safety. Instead, the idea of "design conditions" is present through nearly every entry in the program. The closest field entry in TRACE that would represent how some might interpret "safety factor" would be the "percent of design capacity" field under the "coils" tab of "Create Systems". TRACE is a load, energy and economic tool intended to provide an accurate analysis representation of the building based on the user entries. The program results can be as moderate or conservative as the user sees fit.

It is the user's responsibility to account for safety factors by using conservative information while inputting the values in the different sections of the program.

What is the difference between zone and room level Coils?

Airside systems can have system-, zone-, or room-level coils and fans. For accurate simulations, correct zoning is essential, because the level of the fans and coils will affect how the rooms and zones should be configured.

A zone-level coil is a coil that serves several room that are grouped together into a thermally similar zone. Each zone has its own thermostat that controls the zone-level coil. Single zone (SZ) and Variable Temperature Constant Volume (VCTC) systems have zone level coils. These systems have only two coils: the cooling coil and the main heating coil. Examples of reports that contain zone level information are: - Zone Checksums Report - Peak Load Summary Report - System Component Selection Report.

A room-level coil is a coil that is located in a room, and only serves the room in which it is located. In this case, every room has its own thermostat to control the room-level coil. Fan Coils PTACs, and Water Source Heat Pumps have room level cooling and heating coils. If a coil is located on the room or zone level, then its selection information (capacity) entering conditions, and airflow) should be taken from a zone or room level report. Examples of reports that contain room level information are: - Room Checksums Report - Peak Load Summary Report - System Component Selection Report.

A system-level unit serves all rooms are zones assigned to that system. System-level units, each airside system would represent an air handler or RTU. All VAV systems have a room level heating coil. That coil could be the main heating coil or the reheat coil, depending on the actual system. To determine the location of all coils in your system, refer to the Schematics tab in Create Systems or the TRACE help entry entitled System Type Characteristics. Reports to look at after the calculation are the System Component Selection report and the System Checksums. This document can also be found in the CDS\TRACE700\Documentation folder.

Why should I zone my building?

In TRACE 700, the Assign Rooms to Systems section of the program is used to configure the rooms and zones on the airside systems. Airside systems can have system-, zone-, or room-level coils and fans. For accurate simulations, correct zoning is essential, because the level of the fans and coils will affect how the rooms and zones should be configured. Three examples are presented in the TRACE 700 Users Manual pp. 6-47-50.

Meet C.D.S. Support

Eric Sturm

Eric joined Trane in 2006 as a marketing engineer with Customer Direct Services (C.D.S.). He is a graduate of the University of Wisconsin-Platteville with a bachelor’s degree in Mechanical Engineering. In his current role, Eric supports customers with many Trane software programs including TRACE 700, System Analyzer, and Engineering Toolbox. Eric is native of North-Central Wisconsin and enjoys all forms of music (especially Blues), building computers, camping, down-hill skiing, and biking.

Q. What three items would you want if stranded on a desert island?

If I were stranded on a desert island, I would take my Led Zeppelin concert collection, a solar-powered device to play the music, and a large supply potable water and food.

Q. What is the most enlightening book you've read in the past year?

I'd have to say the TRACE 700 Users Manual.