Dedicated Outdoor Air Systems: Balance Between IAQ and Energy

Dedicated Outdoor Air Systems and ASHRAE 62
5/14/2014
Brian Monk, PE
Sales Manager, Carrier Racan
Montreal, Canada
© 2014 Carrier Corporation
EDUCATION AND CREDENTIAL CREDITS
In order to receive a certificate for this course you must:
1. Sign the workshop attendance sheet which demonstrates
that you have attended the workshop.
This will be passed around the room at the start of each workshop.
Print legibly so that information can be easily verified.
2. Turn in the completed Evaluation to the moderator.
If you hold a PE license in Florida, New York or North Carolina
please sign the appropriate sheets and include your registration
number
Under the November 2012 rule, this course may qualify for
GBCI LEED CMP credit under the Educational Category
If you would like to have an Adobe PDF copy of any of the presentations,
go to www.carrieruniversity.com and look under Sustainability Symposiums.
LEED is a registered trademark of the U.S. Green Building Council.
© 2014 Carrier Corp.
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Dedicated Outdoor Air Systems and ASHRAE 62
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LEARNING OBJECTIVES
1. Outline specific sections of ASHRAE Standard
62.1 as it applies to building filtration
2. Identify various AHU design strategies that can
comply with ASHRAE 90.1 as it pertains to
building energy recovery
3. Understand the limitations of filtration technology
that can be incorporated into custom DOAS to
minimize airborne contaminants
4. Select methods of reducing life-cycle cost without
sacrificing adequate environmental quality
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SUMMARY OF PRESENTATION
• Outdoor Air (Standard 62.1)
• Energy Recovery Technology
• DOAS Configurations
• Engineering Evaluation
• Control Strategies
• DOAS and Chilled Beam
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BENEFITS OF ENERGY RECOVERY
• Environmental and Sustainable
Design Practice
• Lower Life Cycle Costs
• Improved Indoor Air Quality
• Compliance with National
Building Codes and Standards
(ASHRAE 90.1)
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EFFECTS OF INCREASED ENERGY COSTS ON DESIGN
Design Decision:
Result:
• Tighter building envelopes
• Reduced amounts of
outdoor air introduced
into the space
•
•
•
•
Occupant discomfort
Poor indoor air quality
Sick building Syndrome
Reduced productivity
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DEDICATED OUTDOOR AIR SYSTEMS
1. 100% OA delivered to each zone via its own ductwork
2. Flow rate generally as specified by
ASHRAE Std. 62.1 or greater (LEED®)
3. Employ Total Energy Recovery (ASHRAE 90.1)
4. Generally Constant Volume
5. Use to decouple space S/L loads
6. Rarely supply at a neutral temperature
7. Use HID, particularly where parallel system
does not use air
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LEED is a registered trademark of the U.S. Green Building Council.
FCU/DOAS ARRANGEMENT
DOAS
OA
EA
RA
OA
SA
SA
RA
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DOAS CONCEPT
Dedicated outdoor air systems (DOAS) can reduce energy use
by decoupling the heating, cooling, and dehumidification of OA
for ventilation from sensible cooling and heating in the zone.
The OA is conditioned by a separate dedicated OA unit that is
designed to heat, cool, and dehumidify the OA, and to deliver it
dry enough to offset space latent loads (Mumma and Shank
2001). Terminal HVAC equipment, which is located in or near
each space, heats or cools re-circulated indoor air to maintain
space temperature. Terminal equipment may include fancoil
units, WSHPs, zone-level air handlers, radiant cooling panels,
fan-powered VAV terminals, or a dual-fan, dual-duct
arrangement. Dedicated OA systems can also be used in
conjunction with multiple-zone re-circulating systems, in which
the ventilation system is sized based on ASHRAE Standard 62.1.
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DOAS CONCEPT
Consider delivering the conditioned OA cold (not reheated to
neutral) whenever possible, and use recovered energy to
reheat only when needed. Providing cold (rather than neutral)
air from the dedicated OA unit offsets a portion of the space
sensible cooling loads, allowing the terminal HVAC equipment
to be downsized and use less energy. In addition,
implementing system-level control strategies and exhaust air
energy recovery can help minimize energy use.
There are many possible DOAS configurations The salient
energy-saving feature of dedicated OA systems is the
separation of ventilation air conditioning from zone air
conditioning.
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© 2014 Carrier Corp.
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PERTINENT STANDARDS ADOPTED BY MANY BUILDING
• ASHRAE Standard 62.1,
“Ventilation for Acceptable Indoor Air Quality”
• ASHRAE Standard 90.1,
“Energy Efficient Design of New Buildings
Except New Low-Rise Residential Buildings”
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BUILDING CODES AND STANDARDS
ANSI/ASHRAE Standard 62.1
Ventilation for Acceptable Indoor Air Quality
Application
CFM/PERSON
Class rooms
15
Offices
20
Smoking areas
60
Retail stores
15
Theatres
15
Bars
30
Banks
15
Metal shop
15
*LEED Can exceed rate by up to 30%
Updates:
• Guidelines for analyzing mechanical cooling systems to help limit space relative humidity.
• Overall decrease in OA if overall space is greater than the number of occupants
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LEED is a registered trademark of the U.S. Green Building Council.
© 2014 Carrier Corp.
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INDOOR AIR QUALITY VS. ENERGY COST (HISTORICALLY)
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OUTSIDE AIR
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VENTILATION RATES
• First, why introduce outdoor air?
‒ To dilute and remove indoor contaminants
‒ To replace indoor air removed by exhaust
• Second, how much outdoor air is needed?
‒ For design, use IAQ Procedure, or
‒ For design, use Ventilation Rate Procedure
Vo = G/(Ci - Co)
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VENTILATION RATE PROCEDURE
• Prescriptive ventilation requirements
‒ Without quantifying Co or G, assumes Ci is
OK if prescribed outdoor airflow is provided
‒ Prescribes space (breathing zone) ventilation
rates in Table 2
• Most widely used procedure
Vo
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OUTDOOR AIR AND EXTRAORDINARY CIRCUMSTANCES
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ASHRAE Standard 62.1
Dilution of Contaminants
Ci = Co + G/Vo
Net* Indoor
Generation Rate
Indoor Target
Concentration
* Emission - Removal
Vo = G/(Ci - Co)
Outdoor
Airflow
Outdoor
Concentration
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OUTDOOR SOURCE CONTROL
Ambient Air Quality
• Regional outdoor air quality must be evaluated
ASHRAE Std 62-2004: “4.1 Regional Air Quality.
The status of compliance with national ambient air quality
standards shall be determined for the geographic area of the
building site. In the United States, compliance status shall be
either in “attainment” or “non-attainment” with ...NAAQS…”
Co
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EMISSION TRENDS (1970-1995)
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EMISSION TRENDS (1970-1995)
Nitrogen Oxide
160
140
120
100
Thousand
80
Short Tons
60
40
20
0
1970 1980 1986 1988 1990 1992 1994
NO
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OUTDOOR SOURCE CONTROL
Intake Separation
• Should separate intakes from strong outdoor sources
• Minimum separation distance from intake for
specific outdoor sources
‒ Cooling tower exhaust ‒ 25 ft
‒ Loading dock ‒ 25 ft
Co
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62.1 OUTDOOR AIR TREATMENT
If Outdoor Air is judged to be unacceptable in
accordance with Section 4.1 (National Ambient
Air Quality Standard), each ventilation system
that provides outdoor air through a supply fan
shall comply with sections following …
Key excerpts from ASHRAE Standard 62.1
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NATIONAL PRIMARY AMBIENT AIR QUALITY STANDARD
(U.S. EPA)
Pollutant
Averaging Period
Standard
Ozone (O3)
Carbon Monoxide (CO)
1-hour
1-hour
0.12 ppm
9 ppm
8-hour
24-hour
Annual arithmetic mean
35 ppm
Particulate Matter (PM-10)
24-hour
Annual arithmetic mean
Annual arithmetic mean
Annual arithmetic mean
0.14 ppm
0.03 ppm
0.53 ppm
1.5 g/m3
Sulfur Dioxide (SO2)
Nitrogen Dioxide (NO2)
Lead (Pb)
150 g/m3
365 g/m3
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MERV FOR PARTICLE FILTRATION
MERV
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Particle
Size
Typical
Pollutants
Applications
Filter Types
 10 m
Pollen,
Dust mites,
Sanding dust
Residential,
Light commercial
Construction,
Throwaway
3-10 m
Dust,
Molds,
Spores
Commercial,
Manufacturing
Pleated,
Panel Filters
1-3 m
Legionella,
Auto Fumes,
Welding Dust
Commercial,
Industrial
Bag, Cartridge,
Mini-pleat
0.1-0.3 m
Tobacco
smoke,
Copier toner,
Bacteria
Commercial,
Medical,
Industrial
Bag, Cartridge
 0.3 m
Sea salt,
carbon dust,
chem-bio,
viruses
Clean rooms,
Surgery,
Isolation
Pleated
MERV 7
Cartridge
MERV 13
Bag
HEPA
MERV 16
ULPA
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GAS FILTRATION
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QUESTION #1
What best describes the advantages of a staged, multiple pass
particulate filter design in a Dedicated Outdoor Air System?
A. This design strategy ensures that all filters address the size of
particle that is predominantly removed in their efficiency range.
B. Multiple pass strategy ensures that minimum fan horsepower
is required to achieve a desired steady state concentration of
particles in the building space.
C. Filter life cycle is optimized since the individual filter stages will
load gradually over time.
D. Filter MERV ratings can be reduced lower than what is
recommended by local code.
Multiple pass filter strategy ensures optimum energy performance
over time by reducing the initial fan horsepower requirement and if
filters are staged adequately, there is no compromise to the steady
state concentration in the space.
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INDOOR AIR QUALITY PROCEDURE
Performance-based requirements
‒ Given Ci target, Co and G values, and find Vo
‒ Lists limits for 10 contaminants,
but open-ended list
‒ Requires a subjective analysis for odors
‒ Describes the use of air cleaning
to reduce OA rates
Vo
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ANSI/ASHRAE STANDARD 62.1-2010
Ventilation for Acceptable Indoor Air Quality
• Ventilation Rate Procedure (VRP)
‒ Conventional prescriptive design approach
‒ OA rate determined by space type, occupancy level & floor area
• Indoor Air Quality Procedure (IAQP)
‒ Performance based design approach
‒ OA and other design parameters determined from an analysis of
contaminant sources, concentration and perceived acceptability
target levels
• Natural Ventilation Procedure (NVP)
‒ Prescriptive design procedure for natural ventilated zones.
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IAQP DESIGN APPROACH
• OA flow rates shall be the larger of those determined with:
‒ Mass balance analysis and
either with
‒ Subjective evaluation or
‒ Similar zone
• Combination of IAQP and VRP
‒ IAQP to address the control of the specific contaminants
‒ VRP to address the general aspects of indoor air quality
of the design space
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MASS BALANCE ANALYSIS

Example
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IAQP EXAMPLE OF GREEN OFFICE
Mass balance analysis - 3 cases of ventilation designs
ASHRAE 62.1 IAQP
ASHRAE 62.1 VRP
5 cfm/person X 80 people
400 cfm OA
(5 cfm/person X 80 people)
+ (0.06 cfm/ft2 X 10,000 ft2)
1000 cfm OA
1.3 X (1000 cfm)
1300 cfm OA
LEED® EQc2
C bz 
N  E zVo 1  E f  C o
E z Vo  RV r E f

For VRP and LEED® cases, Ef = 0
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LEED is a registered trademark of the U.S. Green Building Council.
© 2014 Carrier Corp.
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QUESTION #2
The use of Outdoor Air as a means of diluting contaminants can
be problematic when the O.A. source is suspected of containing
pollutants. Which design documents should be considered?
A. ASHRAE Standard 62.1, IAQ Procedure
B. ASHRAE Standard 90.1
C. CDC 1994 “Guidelines for preventing the
transmission of Mycobacterium TB”
D. All of the above
ASHRAE Standard 62.1(section 4) specifically outlines procedures
that must be followed when there is a concern for Regional or Local
air quality in outdoor air.
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QUESTION #3
ASHRAE Standard 62.1 outlines specific design features that must be
included in HVAC systems with regards to moisture management.
When designing a DOAS, which of the following should be considered?
A. Drain pan slope shall be 0.125 in/ft minimum from the horizontal.
B. Multiple drain pans for every section in the AHU.
C. Adequately sized P-traps for every section that includes drains,
to facilitate water drainage during washdown cycles.
D. Drain pan should be as long as possible in case of carryover from any
water generating device.
Drain pan slopes are clearly identified
in section 5.11.1 of Standard 62.1
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BUILDING CODES AND STANDARDS
ASHRAE Standard 90.1 <Section 6.5.6.1>
Energy Standard For Buildings Except Low Rise Residential Buildings
A standard to provide minimum requirements
for the energy-efficient design of buildings
When:
SA ≥ 5000 cfm
and
OA ≥ 70% of SA
Then:
E min ≥ 50%
Exception:
EA ≤ 75% of OA
Minimum Effectiveness
for total energy recovery
Enthalpy (latent +sensible)
Laboratory exhausts
Fume exhausts including kitchen exhausts Std
62.1-2007 allows its use with class 1-3 air
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PERTINENT EXCERPT FROM 90.1
6.3.6.1 Exhaust Air Energy Recovery
Individual fan systems that have…a design
supply air capacity of 5000-CFM or greater
and have a minimum outside air supply of
70% or greater…shall have an energy
recovery system with at least 50% recovery
effectiveness….[which] shall mean a
change in the enthalpy of the…supply equal
to 50% of the difference between the
outdoor air and return air at design
conditions.
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VENTILATION LOAD INDEX
High Latent to Sensible Ratio
Medium Latent to Sensible Ratio
Low Latent to Sensible Ratio
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HUMAN COMFORT ZONES
ASHRAE Summer and Winter Comfort Zones
(Acceptable Ranges of Operative Temperature and Humidity
for People in Typical Summer and Winter Clothing During
Primarily Sedentary Activity).
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TYPICAL PSYCHROMETRICS
EW
5
RA
OA
2
1
PH
4
3
Space
CC
2
Hot & humid
OA condition
3
5
4
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ENTHALPY WHEEL IN DOAS
• A significant reduction in the design OA cooling load,
reducing both the chiller size and the peak demand
• A reduction in the annual OA cooling and dehumidify
energy consumption
• A significant reduction in the OA heating and
humidification energy consumption (in the North)
• Conforms to ASHRAE Standard 90.1-2007
• A major reduction in the variability of the OA
conditions entering the CC
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APPLICATION CATEGORIES
• Comfort-to-Comfort
‒ (Standard HVAC Applications)
• Process-to-Comfort
‒ (Light Industrial Applications)
• Process-to-Process
‒ (Heavy Industrial Applications)
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SURVEY OF EXISTING TECHNOLOGIES
Thermosiphon
Heat Pipe Heat Exchanger
Fixed-Plate Heat Exchanger
Rotary Wheel
Coil Recovery Systems
(Runaround Loop)
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ENERGY RECOVERY SOLUTIONS IN DOAS
• Heat Pipe Heat Exchangers
• Fixed Plate Heat Exchangers
• Rotary Air-to-Air Heat Exchangers
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PASSIVE VS. ACTIVE ENERGY RECOVERY
Passive Systems
No external energy source
is required for heat transfer
to take place.
Active Systems
Continuous external energy
input is required for heat
transfer to take place.
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DOAS AND ENERGY RECOVERY
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ENERGY RECOVERY
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PASSIVE VS. ACTIVE ENERGY RECOVERY
Passive Systems
•
•
•
•
Thermosiphon
Heat Pipe
Fixed-Plate
Rotary Wheel
Active Systems
• Rotary Wheel
• Coil Recovery Systems
(Runaround Loop)
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HEAT PIPE HEAT EXCHANGER
Advantages:
• 0% Cross Contamination
• Size Flexibility
• Ideal for Retrofit
Considerations:
• Low Sensible Effectiveness
(45 to 55%)
• Installation Sensitivity
• Higher Cost
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FIXED PLATE HEAT EXCHANGER
Advantages:
•
High sensible effectiveness (60 to 70%)
•
Durable construction
•
Low maintenance
•
Cross-flow HX provides best
price-to-performance
(and performance-to-pressure drop) ratio
Considerations:
•
High pressure drop associated with
counter-flow heat exchangers
•
Higher cost associated with
counter-flow heat exchangers
•
AHU layout
49
THEORY OF OPERATION
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ROTARY HEAT EXCHANGER
Advantages:
•
•
•
•
High total effectiveness (75% to 80%)
Self-cleaning effect
Available as sensible or enthalpy device
Low pressure drop, low maintenance,
and low carry-over with proper enthalpy
wheel supplier
Considerations:
• Possibility of carry-over
for critical applications
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THEORY OF OPERATION
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PASSIVE VS. ACTIVE WHEELS
Passive Wheel
Active Wheel
• Energy recovery / energy
transfer is the primary
objective
• Humidity control is the
primary objective
(typically low-dew-point
desiccant dehumidification)
• Comfort-to-comfort
application
• No regeneration heat
is required
• Regeneration heat is
always required
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SILICA GEL VS. MOLECULAR SIEVE
Silica Gel
Molecular Sieve
• Wide pore structure
• Typically 3A to 4A
• Affinity for water vapor
• High retentivity
(very strong bond)
• Low retentivity
(weak Van der Waals bonds) • Without regeneration heat
a layer of water vapor is
• Optimal operating range
always present on the
found in typical HVAC
surface of the exchanger
applications
• Optimal operating range
under low humidity
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SILICA GEL VS. MOLECULAR SIEVE
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ENGINEERING EVALUATION
• Passive vs. Active Systems
• Carry Over or Cross-Contamination
• Sensible vs. Total Energy Recovery
• Pressure Drop
• Frost Control Strategies
• Thermodynamic Performance
Requirements
• Life Cycle Cost / Operational Control
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GENERAL FROST CONTROL STRATEGIES
• Face and Bypass
• Preheat Frost Control
• Exhaust Only Defrost
• Recirculation Defrost
Not
Recommended
• On/Off
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TECHNOLOGY SPECIFIC STRATEGIES
• Tilt Control
• Traversing Defrost
• Cold Corner Defrost
• Speed Control
(VFD/VSD)
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THERMODYNAMIC EVALUATION
Assumptions and Design Considerations
Nominal Airflow: 5000-CFM
Heat Exchanger Design Velocity: 450 FPM
ARI Design Conditions*:
Summer
OA Temp.: 95°F db / 78°F wb
RA Temp.: 75°F db / 63°F wb
Winter
OA Temp.: 35°F db / 33°F wb
RA Temp.: 70°F db / 58°F wb
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HEAT EXCHANGER PERFORMANCE COMPARISON
Heat Pipe
53,935 btu/hr (4.5 tons)
50% Sensible Effectiveness
Fixed Plate
65,903 btu/hr (5.5 tons)
60% Sensible Effectiveness
Enthalpy Wheel
149,000 btu/hr (12.4 tons)
79% Total Effectiveness
83°F db
75°F wb
83°F db
75°F wb
95°F db
78°F wb
79.2°F db
66.7°F wb
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OUTDOOR AIR SYSTEMS DESIGN
Design Objectives
Human Comfort
Depends on:
‒ Geographic Location
‒ Application Requirements
‒ Appropriate Levels of
Temperature and Humidity
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OUTDOOR AIR SYSTEMS DESIGN
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ENERGY RECOVERY SYSTEMS
• Standard ERVs/HRVs
• Packaged Recovery Systems
• Neutral Air Systems and
Dedicated Outdoor Air Systems
(DOAS)
• Partial Outdoor Air Applications
• Custom Recovery Systems
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ENERGY RECOVERY DESIGN EXAMPLES
• Energy Recovery Pre-Cooler
Re-Heater (Wrap Around)
• Sensible Energy Recovery
• Enthalpy Recovery
• Passive / Active Desiccant
• Total + Sensible Recovery
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100% OUTSIDE AIR CONDITIONING
OA
SA
1
2
3
SUMMARY
1
Cooling Required: 67 Tons
Heating Required: 215 MBH
2
3
65
ENERGY RECOVERY PRE-COOLER RE-HEATER
SUMMARY
Cooling Required: 47 Tons
Heating Required: None
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TYPICAL ARRANGEMENTS
67
SENSIBLE HEAT RECOVERY
OA
SA
1
2
3
EA
4
RA
2
1
SUMMARY
Cooling Required: 53 Tons
Heating Required: 215 MBH
3
5
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QUESTION #4
In order to optimize energy performance of a DOAS,
typical component configuration should include?
A.
B.
C.
D.
Hot gas reheat capability
Active desiccant wheel
Enthalpy wheel with cooling coil
DX cooling using a non-CFC refrigerant
Although DOAS can include many different components,
enthalpy wheels provide the best return on investment
as a pre-heating/pre-cooling device.
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TOTAL AND SENSIBLE RECOVERY
SA
OA
1
2
3
EA
4
5
RA
1
2
SUMMARY
Cooling Required: 22 Tons
Heating Required: 75 MBH
3
4
5
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DOAS COMPONENT CONFIGURATION
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DOAS ENTHALPY WHEEL CONTROL
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DOAS CONTROL
73
CO2 - BASED DCV
How does CO2-based DCV work?
• Start with Ci = Co + G/Vo
• Tests show 80% of visitors are OK with human
bioeffluent odors at outdoor airflow Vo = 15 cfm/p
• Sedentary people generate CO2 at 0.0105 cfm/p
• If Co = 300 ppm, Ci = 300 + 10500/15 = 1000 ppm
• So, Ci - Co = 700 ppm corresponds to 15 cfm/p
in offices
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QUESTION #5
A Dedicated Outdoor Air System shall include the
ability to conserve energy from exhaust air when?
A. The design temperature for the region is a minimum
20F difference from the set-point of the indoor space.
B. The DOAS has a design supply air capacity of 5000-CFM or
greater and has a minimum outside air supply of 70% or greater.
C. Outdoor air contaminants are below the NAAQS guidelines.
D. A designer is trying to increase the amount of LEED® EA credits.
ASHRAE Standard 90.1 section 6.3.6.1 “Exhaust Air Energy Recovery”
recommends the use of an energy recovery system with a minimum
effectiveness of 50%.
LEED is a registered trademark of the U.S. Green Building Council.
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ENERGY EFFICIENT AHU DESIGN
• Properly selected heat exchanger
• Proper design and selection of components
‒ Efficient fan selections
‒ Variable speed motors
‒ Proper filtration stages
• Cabinet construction
‒ Double wall center partition
‒ Low leakage rates
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TOTAL ENERGY SAVINGS
DOAS using variable speed:
1) Supply / Exhaust Fans
2) Air-Cooled Condenser Fans
3) Enthalpy Wheels
4) Compressors
Variable speed compressors
• Typical Capacity range from 50-150%
•
Environmentally-friendly R410a refrigerant
•
Control to set point
•
Elimination of hot gas bypass
•
High part load EER
•
Low inrush current
•
Internal oil management system all speeds
77
ENERGY SAVINGS
Above graph is based on energy consumption necessary to cool
and dehumidify 100% outdoor air to 55F at part load conditions.
Information is based on data provided by S.A. Mumma, Ph.D., P.E. (May 4, 2011)
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ASHRAE’S BEST
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ENERGY SAVINGS
In addition, they also considerably trim down heating and cooling demands,
allowing designers to downsize equipment capacity. To enhance heat
exchange, wheel selections should be made to limit air
velocity at 600 fpm (3.05 m/s). To prevent frost from
forming on the wheels, glycol preheating coils should
be installed. Enthalpy wheels are programmed to
work when outdoor temperatures drop below 50°F
(10°C) or rise above 77°F (25°C). Between 50°F and
77°F, (10°C to 25°C) enthalpy wheels are no longer
profitable, since they can increase cooling energy to a
point that will exceed heating and humidity savings.
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Dedicated Outdoor Air Systems and ASHRAE 62
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LEED-NC(v2.2) EA Credit 1
Chiller Plant Efficiency: Series Counter-Flow
• Compare ASHRAE 90.1-2004
“Baseline” Building vs. “Proposed” Building
with 2-Series Counter-Flow Chillers
• Cooling Tower Optimization
• Correct design WB, flow and temperature
makes a difference
• Series Counter-Flow + DOAS + Chilled Beam
• Increase LEED ® Points
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LEED is a registered trademark of the U.S. Green Building Council.
800-TON COMMERCIAL OFFICE BUILDING WITH DATA CENTER
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PROJECT DATA: (BASELINE AND PROPOSED)
Description
Baseline
Proposed
Design Model
Same as Proposed
ASHRAE 90.1-2004 Table G3.1
Space Usage Classification
“
“
“
“
“
“
“
Building Envelop and Schedules
“
“
“
“
“
“
“
Ventilation
“
“
“
ASHRAE 62.1-2004
Lighting
“
“
“
ASHRAE 90.1-2004 Table G3.1
Thermal Blocks
“
“
“
“
HVAC Systems
VAV, CW/HW per ASHRAE 90.12004 G3.1.1 through G3.1.3
Series Counter-Flow, DOAS,
Active Chilled Beams
Service Hot Water
Same as Proposed
ASHRAE 90.1-2004 Section 7.4.2
Receptacle and Plug Loads
25% of Total Building Energy Cost
25% of Total Building Energy Cost
“
“
“
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DEDICATED OUTDOOR AIR SYSTEM
• 100% Outside Air
• 50% Effective ERV
• Chilled Water Coil, 44/54°F
• Fan Hp per ASHRAE 90.1-2004
• Filtration per ASHRAE 62.1-2007
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Dedicated Outdoor Air Systems and ASHRAE 62
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SERIES COUNTER-FLOW CHILLER PLANT
•
•
•
•
Primary Variable Speed Loop,
Secondary Active Chilled Beam Loop
44/60°F with reset
Chilled water pump sized for 100ft head
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ACTIVE CHILLED BEAM
• Induction air current mixes room air with ventilation air.
• Sensible cooling provided by chilled water coil.
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HOURLY ANALYSIS PROGRAM (HAP)
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LEED is a registered trademark of the U.S. Green Building Council.
PERCENT IMPROVEMENT
Reference: LEED ® -NC 2.2 EAc1 Compliance Calculator (v8.1)
88
LEED is a registered trademark of the U.S. Green Building Council.
© 2014 Carrier Corp.
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Dedicated Outdoor Air Systems and ASHRAE 62
5/14/2014
DETERMINE LEED® CREDIT POINTS FOR PROPOSED BUILDING
• EAc1 Points
• % Savings = $ 860,380 – $556,468 = 35.32 %
$ 860,380
8 points
New Construction
or
Major Renovation
EA Credit Points
10.5%
1
14.0%
2
17.5%
3
21.0%
4
24.5%
5
28.0%
6
31.5%
7
35.0%
8
38.5%
9
42.0%
10
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LEED is a registered trademark of the U.S. Green Building Council.
REFERENCES
Schoen, Larry: “ASHRAE Std 62, Ventilation for Acceptable Air Quality”. Boston Society of Airchitects, Chapter of AIA, May
2004.
Vasselli, John: “Economics and Energy in Buildings”. Bynum Training Center, Carrier Corporation, NOV 2006.
Mumma S.A. 2001.”Designing Dedicated Outdoor Air Systems”, ASHRAE Journal, May 2001.
U.S. Environmental Protection Agency Office of Mobile Sources. Air Toxics from Motor Vehicles. February, 1995.
U.S. Environmental Protection Agency Office of Mobile Sources. Environmental Fact Sheet - Adopted Aircraft Engine
Emission
Standards. August, 1994.
Mumma, S.A. 2008.”DOAS and Desiccants”. DOAS Supply Air Conditions, IAQ Publications Spring 2008.
ASHRAE Guest Column.
McDowell, Thimothy et al. “Analysis of Dedicated Outdoor Air Systems for Different Climates”.
Ninth International IBPSA Conference, Montreal , Canada,
August 2005.
Chang, K.M., The Integration of Airport Planning and Environmental Assessment - A focus on Air Quality Analysis, 1978.
Pant, Bhuvan C., Diesel Exhaust Irritants and Odorants, Materials Research, Development and Production Center, 1987.
Persily, Andrew: ASHRAE Standard 62.1-2004 “Introduction and Overview. ASHRAE Winter Meeting, Orlando , FL, Feb
2005.
Carrier Corporation:”Demand Controlled Ventilation System Design”.Saving Energy Cost while optimizing Indoor Air
Quality.
Syracuse 2001.
Stanke, Dennis. “System Operation: Dynamic Reset Option”, Standard 62.1-2004. ASHRAE Journal December 2006
ACGIH. 2001. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices.
American Conference of Governmental Industrial Hygenists.
Mumma, S.A. 2006. “DOAS Design and Application, Avoiding Pitfalls”, ASHRAE Publications 2006.
ASHRAE Technical Publications.
Burroughs, H.E. “Energy Savings with Acceptable IAQ in a Renovated Office Space”, ASHRAE Publications, 2008.
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Dedicated Outdoor Air Systems and ASHRAE 62
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THANK YOU!
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