freshman iq - wordpress.comenergy consumption. the equipment with the lower total cost of ownership...

Freshman IQ Intelligently Quiet choice for classroom environments

<NC30

Freshman IQ: Intelligently Quiet choice2

© Systemair 2014We reserve the right to make technical changes. For updated documentation, please refer to www.changeair.com

Our data speaks volumes

2011 ASHRAE Applications Handbook, Chapter 48, Noise and Vibration Control cites ANSI/ASA Standard S12.60-2010 for classroom acoustics as a guideline for school mechanical design.

”Accurate acoustical analysis of HVAC systems depends in part on reliable equipment sound data. When reviewing manufacture’s sound data, obtain certification that the data have been obtained according to one or more of the relevant standards. If they have not, the equipment should be rejected in favor of equipment which data have been obtained according to relevant industry standards. See Ebbing and Blazier (1998) for further information”.

In addition the Handbook clarifies,

“Whenever possible, data obtained by the AHRI 260 method should be used because it eliminates much of the uncertainty present in the fan-plus-algorithm method”.

Freshman IQ by ChangeairTested in Accordance with AHRI 260 in an accredited reverberant laboratory, Freshman IQ units provide reliable data when you are designing classrooms that meet ANSI/ASA Standard S12.60-2010, Acoustical Performance Criteria, Design Requirements and Guidelines for Schools.

Freshman IQ: Intelligently Quiet choice 3

Content

Teach with confidence 4Provides the perfect environment for learning.

Design with confidence 10Utilizes data gathered in an accredited reverberant laboratory.

Built & Tested with confidence 16Tuned and tested to perfection.

Maintain with confidence 30Quality, reliability and ease of maintenance, all in one package.

Changeair was established to meet the difficult ventilation needs of classroom environments that require exceptional ventilation and noise control with heating and cooling options. New and existing structures needed flexible solutions for healthier and more productive learning and working conditions. Changeair responded with new technology and application driven design to produce classroom air handlers that are cost effective and versatile.


Teach with confidenceTeachers, I believe, are the most responsible and important members of society because their professional efforts affect the fate of the earth.

Helen Caldicott, Australian physician

4


Challenges of classrooms

Noisy classrooms = Disadvantaged students and educators

How many times would you ask someone to repeat themselves before giving up on hearing what was said? Most adults ask once, maybe twice, before embarrassment overtakes their desire to learn. A child in a classroom is unlikely to ask at all.

The fact is school age children hear only about 75% of what teachers say in the classroom. The rest is drowned out by the fierce background noise—noise that is in part due to HVAC equipment. Excessive classroom noise handicaps the performance of teachers and students and undermines the confidence they have in each other and in themselves.

A serious problem in our schools

Within the last two decades numerous studies have shown that persistent classroom noise has a significant effect on the stress level and physical health of teachers and the ability of students to learn and perform. Poor acoustics ranks among the highest complaints in schools. In one survey, 28% of the schools reported acoustics as an unsatisfactory environmen-tal condition.

Other studies have shown that poor interior acoustics neg-atively effect the social-emotional class atmosphere. Noisy, reverberant classrooms force teachers to speak in a perma-nently raised voice. Patience levels wane as they constantly warn children to be quiet, which increases stress levels on the students.

Children hear onlyabout 75% of what teachers say in the classroom


Background noise

HVAC equipment and ventilation flow generate background noise. This raises the level of noise in a classroom, which in turn requires the teacher’s voice to increase in order to be heard.

The increase is generally accepted to be about +15 dB. In a classroom with a Background Noise Level (BNL) of 35 dB(A) the teacher must speak at least 50 dB(A), however sound diminishes as it travels and the BNL is typically constant in

a classroom. Much like dropping a pebble in a pond, at the source the sound amplitude (wave height) is higher, thus louder. As the wave travels it loses energy and its amplitude decreases.

Therefore to be heard at the back of a classroom the teacher must speak even louder than 50 dB(A).

Typical values are 60-65 dB(A).

Speaker to listener distance, ft

0 3 6 9 12

Loud

ness

, dB(

A)

0.0

20.0

40.0

60.0

80.0

15 18 21 24 28

+15 dB+9 dB

+3 dB

-3 dBbackground noise

35.0

If the HVAC equipment you select creates a BNL of 45-55 dB(A), then the teacher must speak at levels of 80 dB(A). Common sounds at 80 dB(A) are a ringing telephone, blender, garbage disposal and food processor.


The maximum level of overall background noise

is a strict 35 dB(A)

The human ear calculates sound at different volumes throughout the spectrum of audible tones. At each octave in tone a certain dB level is required for that tone to be heard.

As shown on the diagram, a lower pitched sound (<250 Hz) must have more dB’s for the human ear to hear it. That is the reason why subwoofers require amplifiers.

Higher tones (>1000 Hz) do not have as much energy to be heard.

HVAC equipment with lower dB levels above 500 Hz are more desirable because they produce less audible sound.

Hz

NC

Lw (R

oom

) dB

63 125 250 500 1000 2000 4000 800010

20

30

40

50

60

70

20

25

30

35

40

45

50

55

60

65

15

Freshman IQ Audible range

Roar & rumble. Poor insulationWhine bearing noise

Hum & buzz airflow

Hiss & whistle. Poor insulation

Conversational speech loudness

Understanding tone

Diagram 1. Sound data for 1,100 cfm airflow Measurement point: 450 cfm of fresh air @ 0.25” ESP


A new standard for classroom acoustics

These facts have not gone unnoticed by the American National Standards Institute (ANSI). As far back as the mid-1990s, ANSI initiated a commission of audiologists, acoustic engineers, educators, architects, manufacturers, and others to begin developing a standard that would address excessive noise in classrooms. Today, that standard is known as ANSI/ASA S12.60-2010 for Classroom Acoustics, and it is applicable to both new classroom construction as well as renovated spaces and modular classrooms.

The standard addresses the issues of classroom noise by placing maximum permissible levels of both reverberation time and background noise. Under the new standard, the maximum level of overall background noise allowed in a classroom is a strict 35 dB(A).

While the ANSI standard is voluntary unless referenced by a code, school districts or States may require compliance with the standard as part of their construction documents for new schools. Increasingly, schools are looking to the standard as a goal, and it is referenced by LEED for Schools as a means to achieving the Acoustic Performance credit.

The maximum level of overall background noise

is a strict 35 dB(A)


Design with confidenceSpeaking as a builder, if you start something, you must have a vision of the thing which arises from your instinct about preserving and enhancing what is there.

Christopher Alexander, architect

10


Two different HVAC philosophiesForget what you think you know

Centralized HVAC systems

Centralized HVAC systems are often recommended as the quietest way to achieve comfort in classrooms. Comfort, of course, requires a delicate balance of temperature, humidity, and ventilation. Providing all of these in an entirely centralized HVAC design creates many challenges for mechanical designers. Individual classroom comfort may be limited by various factors, including the design, duct layout,

and the quality and effectiveness of the control system. Moreover, a central system requires considerable maintenance to survive to its full 20-25 year life span. The structural and mechanical designs are complicated by a large system being utilized to condition many smaller, dynamic spaces.

Decentralized HVAC systems

Decentralized systems, which rely on unitary equipment in individual spaces, are typically less expensive to install and maintain, and offer much more in the way of classroom comfort. Despite these advantages, however, decentralized systems are often ruled out in schools because of noise, when engineers are designing classrooms that meet ANSI Standard S12.60-2010, Acoustical performance criteria, design requirements and guidelines for schools.

A perfect solution would be a quiet classroom air handler capable of providing high efficient heating and cooling, ventilation and humidity control, the best thermal control incorporating energy recovery; a unit sound tested in accordance with AHRI 260, using an AMCA accredited reverberant laboratory (AMCA Standard 300-08).

Such a solution was not thought to exist – until now.

ComfortBuilding use

flexibilityCost

IAQZonecontrol


There are many selection criteria used to determine the mechanical ventilation needs of a school application: Community use, Total cost of ownership, Classroom footprint, Energy efficiency, Ease of maintenance and Sound. Not all HVAC equipment is created equal to provide thermal comfort and indoor air quality the same way. These criteria are not all weighted the same.

Time to retune your school HVAC selectionSystem comparison

Central Roof Top Unit - A large, centralized air handler for ventilation, with primary heating and cooling built in. Energy recovery may/may not be included. Large duct runs are required. The roof must be designed to support the load and where necessary the snow load. VAV’s and zone controls.Zone Roof Top Unit - Several smaller roof top air handlers for ventilation, with heating and cooling built in. Energy recovery may/may not be included. Less supported weight on the roof. VAV’s and zone controls.Ceiling Hung Cassette - Each independent space or room is thermally monitored and controlled locally. Ventilation is managed by either a large or zone outside air system.Therminal Unit Packaged AC - A compressorized classroom air handler, with primary heating, cooling, ventilation and energy recovery (optional).Intelligently Quiet Terminal Unit Split AC - A non-compressorized classroom air handler, with primary heating, cooling, ventilation and energy recovery (optional). The compressorized section is outside the classroom on the roof.

Exceeds requirementsLegend Meets requirements Doesn’t meet requirements

Community useMunicipalities are combining community centres, libraries, municipal offices, pool, gym and other functions into the local school. High Schools may include the neighbourhood pool. The perfect scenario is a mechanical system that only condi-tions the space that is being used.

Total cost of ownershipWhen choosing a system, buyers should look not just at an item’s first cost, but rather at the total cost of ownershit, which includes equipment life span, maintenance cost and energy consumption. The equipment with the lower total cost of ownership can outweight cheaper alternatives. Ease of maintenanceEase of maintenance considers both the routine and major maintenance for the entire building. The number of decentralized units can be a better solution than a central system during shutdown periods. The terminal classroom air handlers are designed specifically to reduce maintenance time and save money.

Energy efficiencyEquipment efficiency is often considered when designing for a classrooms HVAC needs. However the law of diminishing returns can mean you could be paying an increased price for equipment with a minimum increase in EER only to find that the increased efficiency will not pay back until the end of the equipments life if at all.

Classroom footprintThe amount of available space in a classroom is high on the list of decision making factors. Equipment, installed in the classroom, will use 2’ x 3’ of usable floor space, which is less than 1% of the floor space.

SoundWhen you consider that a 10 dB(A) reduction makes the space half as loud, is there any reason to select HVAC equip-ment on any other criteria? The quality of children’s educa-tion, the reduction in teacher voice strain, the improvement in the classroom environment all far outweigh a minor cost savings on HVAC equipment.

Central Roof Top Unit Zone Roof Top Unit Ceiling Hung Cassette Terminal Unit Packaged AC IQ Terminal Unit Split AC

Sound Rating

Cost of Ownership

Total Footprint

Energy Efficiency

Building Structural Cost

Ease of Maintenance

Community Use

Table 1. System comparison

Freshman IQ: Intelligently Quiet choice14 Freshman IQ: Intelligently Quiet choice14

LEED®Leadership in Energy and Environmental Design

Today’s school buildings are designed to be sustainable, adaptable, and energy efficient. Changeair is committed to helping design and construction professionals achieve these goals. We offer solutions for indoor air quality and unsurpassed project support.

We can assist you with designing your project, ensuring that the indoor environmen-tal quality complements your unique vision. The Freshman IQ sound package allows you to meet the specific requirements of the latest environmental design criteria, including the LEED® Green Building Rating Systems.

LEED is a rating system started in 1998 and administered by the United States Green Building Council (USGBC).

It provides an objective national standard for what constitutes a green building. It offers a set of scientifically based performance criteria for LEED project certification.


LEED for schools: New construction and renovations

The LEED for Schools rating system recognizes the unique nature of the design and construction of K-12 schools. It addresses issues such as classroom acoustics, master planning, mold prevention and environmental site assessment. By addressing the uniqueness of school spaces and children’s health issues, LEED for Schools provides a unique, comprehensive tool for schools that wish to build green, with measurable results.



Built and Tested with confidenceManufacturing is more than just putting parts together. It’s coming up with ideas, testing principles and perfecting the engineering, as well as final assembly

James Dyson, Industrial designer

16


Built and Tested with confidence

17


Sound data you can trust

The Systemair laboratory is designed and equipped to per-form testing in accordance with AMCA Standard 300, Rever-berant room method for sound and AMCA Standard 210 for airflow performance.

Since the lab first earned AMCA accreditation, Systemair has worked to continually increase the lab’s capabilities. This com-mitment to continued growth has allowed for testing units in accordance with other standards and requirements, such as AHRI 260 testing, safety regulatory agency testing like UL and CSA, vibration testing, and full power analysis.

Sound and airflow test laboratoryOur dedication to education

Sound power testing—performed at 1/3 Octave band from 50 to 10,000 Hz, in accordance with AMCA Standard 300.

Airflow testing—conducted up to 60,000 cfm at 3” of static pressure (Pst) or 30,000 cfm at 10” of static pressure (Pst), in accordance with AMCA Standard 210.

Tested in accordancewith AHRI 260 in an accredited laboratory

Freshman IQ: Intelligently Quiet choice 19Freshman IQ: Intelligently Quiet choice 19


Freshman IQVertical non-compressorized air handler

Exterior

The Freshman IQ vertical classroom air handler is designed for compatibility and flexibility. The IQ package is available with supply air capacities from 700 to 1,800+ CFM and in two of our cabinet sizes (h x w x d):

B: 91” x 39 3/4” x 25” C: 91” x 46 3/4” x 25”

The Freshman IQ offers the most versatile air handler solution for quiet, comfortable and healthy indoor environment. It offers a rich resource of road tested designs and configurations with a near unlimited ability to customize both cabinets and internal options.

Quiet, comfortable and healthy indoor environment


Standard package:

• Steel internal frame with factory powder coat finish on external panels

• Dual action cam lock fastening system on hinged/lift door

• 1” of sound absorbing insulation in cabinet wall and service panels

• Spring return damper actuators on aluminum airfoil outside air dampers

• 2 or 4 pipe Hydronic or Split DX

Optional package:

• Face and bypass damper design• Energy Recovery Wheel (ERW) available with one relief 450 CFM fan• Powered relief fan built into the unit

Interior

To meet your ventilation needs a Freshman IQ air handling unit can be configured with a variety of heating and cooling coil packages.

The unit comes standard with a low leakage airtight outside air damper and electrically commutating (EC) motor fan to meet your ventilation and free cooling needs. The unit is available in standard or optional power relief, energy recovery or face and bypass configurations.


Top 8 features of the newest Freshman SeriesThis changes everything

Electronically Commutated motors (ECM)

Steel solid frameThe internal frame supports all the internal metal

panels and components so that the external panels do not carry any of the weight and reduce the

potential for sound transmission.

Enhanced coilOur aluminum wave fin coils were specifically engineered to enhance sound performance while maximizing efficiency.

Attenuating return plenumThe plenum is designed to absorb sound energy and effectively reduce the direct path of sound radiating through the intake grille.

Not only do they offer a greater efficiency range with minimumal noise, they are also mounted in a dual fan assembly which is double isolated from the unit's structure.


Non-toxic acoustic insulation The cabinet panels are thermally and

acoustically insulated with 1”(2.54 cm) thick flexible acoustic insulation.

Acoustically engineered doors and panels

Designed specifically to reduce case radiated sound from the air handler

Laminar intake grilleIts laminar flow fixed blades direct the intake air into the unit quietly.

Airtight cabinetOur unique manufacturing process ensures

an airtight cabinet seal free of unwanted and unnecessary sounds.


Parameter Unit Cabinet B Cabinet C

Voltage V / ~ Up to 460 / 3 Up to 460 / 3

Maximum airflow cfm 1,600 2,200

Heating - Hot water Hot water

Cooling - DX or Chilled water DX or Chilled water

Design types - Standard or face bypass Standard or face bypass

Filter, 2” or 4” - MERV 8 MERV 8

Weight lbs 675 850

Classroom air handling unitQuick reference

Changeair is committed to helping design and construction professionals achieve their goals. Not only do we offer solutions for indoor air quality, we can assist you with designing any unsurpassed project, ensuring that the indoor environmental quality complements your unique vision. The Freshman IQ sound package allows you to meet the specific requirements of the latest environmental design criteria, including the LEED® Green Building Rating Systems.

For more information, visit www.changeair.com

Table 2. Specification data


Diagram 2a. Various supply CFM ratings and corresponding sound levels, dB(A) and NC

18.0

23.0

28.0

33.0

38.0

43.0

48.0

58.0

700 800 900 1000 1100 1200 1300 1400 1500

53.0

NC @ 0.00” ESP

NC @ 0.25” ESP

dB(A) @ 0.00” ESP

dB(A) @ 0.25” ESP

dB(A

) & N

C

cfm

All test data obtained in an accredited reverberant laboratory and tested in accordance to AHRI Standard 260, Sound Rating of Ducted Air Moving and Air Conditioning Equipment.

Diagram 2b. Sound levels, dB (A) vs distance, ft for various supply CFM ratings for a typical classroom typical classroom 30’ x 30’ x 9’ (As per Chapter 8.8 of ASHRAE Fundamentals Handbook)

dB(A

)

Feet

84 6 10 12 14 16

20.0

25.0

30.0

35.0

40.0

45.0

1,000 cfm @ 0.00” ESP

1,400 cfm @ 0.00” ESP

1,200 cfm @ 0.00” ESP

800 cfm @ 0.00” ESP

1,000 cfm @ 0.25” ESP

1,400 cfm @ 0.25” ESP

1,200 cfm @ 0.25” ESP

800 cfm @ 0.25” ESP


Hz

NC

Lw (R

oom

) dB

63 125 250 500 1000 2000 4000 800010

20

30

40

50

60

70

20

25

30

35

40

45

50

55

60

65

15

Lwradiated @ 0.00“ ESP Lwradiated @ 0.25“ ESP

Diagram 3. Sound data for 800 cfm airflow Measurement point: 450 cfm of fresh air

FRESHMAN SoUND DATA

800 CFM

ESP Frequency bands, Hz

63 125 250 500 1000 2000 4000 8000 dB dB(A) NC

Lwradiated 0.00” 54.2 48.8 34.4 26.7 19.6 18.1 23.8 19.8 55.4 35.6 18

0.25” 62.7 55.1 39.8 30.1 22.9 16.6 23.7 25.8 63.4 41.8 26

Lwdischarge 0.00” 61.8 61.4 57.2 56.2 52.3 46.7 39.6 35.8 66.1 - -

0.25” 70.8 67.3 63.8 60.1 57.8 53.4 46.0 35.5 73.4 - -

Table 3. Sound data for 800 cfm airflow Measurement point: 450 cfm of fresh air @ 0.25” ESP



Hz

NC

Lw (R

oom

) dB

63 125 250 500 1000 2000 4000 800010

20

30

40

50

60

70

20

25

30

35

40

45

50

55

60

65

15


Diagram 4. Sound data for 1,000 cfm airflow Measurement point: 450 cfm of fresh air

FRESHMAN SoUND DATA

1,000 CFM

Table 4. Sound data for 1,000 cfm airflow Measurement point: 450 cfm of fresh air @ 0.25” ESP



63 125 250 500 1000 2000 4000 8000 dB dB(A) NC

Lwradiated 0.00” 55.9 52.6 37.6 30.1 22.4 17.8 23.8 20.4 57.6 38.6 23

0.25” 62.1 56.6 41.3 32.5 25.2 18.5 23.7 25.8 63.2 42.8 28

Lwdischarge 0.00” 70.3 63.8 57.4 58.2 53.8 49.0 42.4 34.7 71.7 - -

0.25” 73.9 70.4 66.4 63.6 61.7 58.8 53.4 44.9 76.5 - -


Hz

NC

Lw (R

oom

) dB

63 125 250 500 1000 2000 4000 800010

20

30

40

50

60

70

20

25

30

35

40

45

50

55

60

65

15



FRESHMAN SoUND DATA

1,200 CFM



63 125 250 500 1000 2000 4000 8000 dB dB(A) NC

Lwradiated 0.00” 59.9 57.5 42.1 34.6 26.7 20.5 23.8 20.1 61.9 43.2 29

0.25” 67.1 62.5 46.7 37.3 30.5 23.6 24.0 25.8 68.4 48.3 35

Lwdischarge 0.00” 74.3 69.5 61.8 62.9 59.3 56.0 51.0 42.9 76.1 - -

0.25” 78.1 74.8 69.9 68.5 67.0 65.5 62.7 56.7 80.9 - -



Hz

NC

Lw (R

oom

) dB

63 125 250 500 1000 2000 4000 800010

20

30

40

50

60

70

20

25

30

35

40

45

50

55

60

65

15



FRESHMAN SoUND DATA

1,400 CFM



63 125 250 500 1000 2000 4000 8000 dB dB(A) NC

Lwradiated 0.00” 64.7 61.9 46.5 38.8 31.1 24.1 24.1 20.4 66.6 47.6 35

0.25” 71.4 66.8 50.9 40.7 34.5 27.6 24.6 25.8 72.7 52.5 41

Lwdischarge 0.00” 76.0 75.5 67.3 67.8 65.4 63.7 60.5 53.5 79.7 - -

0.25” 80.3 77.0 72.1 71.6 70.5 69.7 68.1 63.1 83.3 - -



Maintain with confidenceThe test of the machine is the satis-faction it gives you. There isn’t any other test.

Robert M. Pirsig, American writer

30


Maintain with confidence

31


Freshman IQEngineered for ease

Simplicity

Freshman units require very little attention to stay running quietly and effectively. Our designers continuously improve the access, reliability and simplicity of our Classroom Air Handlers.

Ease of maintenance

Our components have been selected for reliability and positioned for ease of access when maintenance is required. To protect against the need to replace components a basic preventative maintenance program will ensure your units last. All components are easily accessed from the front doors.

Controllability

The power of a Changeair unit’s modulation capability is best experienced with Factory supplied controls. With 20 plus years of programming our units we can positively provide the most effective control in all modes of operation.

Cost of ownership

With the equipment mounted indoors, the overall life span is longer than roof mounted equipment. The quality of the components allows for significantly long life spans. The decentralized concept ensures that energy consumption and recovery is maximized for every space.


Kids learn better in schools with good lighting, clean air, and comfortable classrooms. That’s why The Collaborative for High Performance Schools® (CHPS) works with schools and experts to make changes to ensure that every child has the best possible learning environment with the smallest impact on the planet. CHPS created the nation’s first green building rating program developed especially for school learning environments, and has the most stringent standards for green school design.

One particular school district chose the Freshman IQ not only for its smaller footprint, improved supply air distribution and easier maintenance access, but the need to comply with CHPS increased energy efficiency and reduced operating sound requirements.

At the Classroom level, the Freshamn IQ unit included an EC Motor, an economizer cycle and MERV 13 filters. To meet the new stringent sound requirements, the units were equipped with the IQ sound package to allow the final classroom design to meet <NC30.

Reference:



Changeair is a part of Systemair

Kuala Lumpur, Malaysia

Skinnskatteberg, SwedenHässleholm, Sweden

Ukmerge, Lithuania

Bratislava, SlovakiaMaribor, Slovenia

Windischbuch, Germany

Madrid, Spain

Hasselager, Denmark

Waalwijk, The Netherlands

Lenexa, USA

Dal, Eidsvoll, Norway

Bouctouche, Canada

Mühlheim a.d.R., Germany

Milano, ItalyIstanbul, Turkey

Langenfeld, Germany

New Delhi, India

Tillsonburg, Canada


History

In the summer of 2012 Changeair was added to the Systemair group of companies. More than 4,500 employees work for more than 60 subsidiaries located in 45 countries making Systemair a leading ventilation company worldwide.

In 1974 in Skinnskatteberg, Sweden the Systemair success story began with the invention of the inline duct fan. Since then the company has continuously advanced. Together with Changeair our goal of high-performance and reliable ventilation holds true.

Systemair companies operate from the core values of simplicity and reliability. Our business concept is to develop, manufacture and market high-quality ventilation products. Our goal is to be known as a company to rely on, with emphasis on delivery, reliability, availability and quality.

Syst

emai

r Inc

. • D

ecem

ber,

2014

Art

. 482

389

www.changeair.com

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