dedicated outdoor air

1
dedicated outdoor air
Application and Design for
The Charles E. and Mary Parente Life Sciences
Building Kings College Wilkes-Barre PA
Ryan James Wanko Building Mechanical and Energy
Systems
2
Charles E. and Mary Parente Life Sciences Building
Overview

• General Information
• Existing Mechanical Conditions
• Dedicated Outdoor air Design
• Smoke Control Units
• Plant Reductions
• Cost Savings and Emission Reductions
• Indoor Air Quality Issues
• Payback Period
• Acoustical Analysis
• Final Comments

doas-radiant
3
Charles E. and Mary Parente Life Sciences Building
General Information

• Construction Start Date December 1997
• Date of Completion August 1998
• 46,000 Square Foot Addition
• 4 stories above grade
• 1 story partially below grade
• Final Cost of 6,056,190
• Budget of 6,100,000

Occupancy Types

• Storage
• Laboratories
• Lecture Halls
• Offices

doas-radiant
4
Charles E. and Mary Parente Life Sciences Building
Project Team Information
Quad 3 Group Joel Sims, AIA, Project
Administrator John Cowder, RA, Project
Architect Brendan Mayer, PE, Mechanical
Engineer Walter Bevilacqua, Electrical
Designer Bernard Ostrosky, PE, Plumbing Lee
Eckert, PE, Structural Engineer Sharon Lehman,
Interiors Prime Contractors General Sordoni
Construction Electric Brennan Electric HVAC
Penn State Mechanical Construction Manager
Sordoni Construction Services
doas-radiant
5
Charles E. and Mary Parente Life Sciences Building
Existing Mechanical Conditions

• 100 Outdoor Air Units
• Delivery of approximately 35,000 CFM
• One of the 4 units is CAV
• Remaining four are VAV in conjunction with
  Phoenix Air Valves
• 2 110 Ton air cooled chilling units
• 2 3753 MBH input natural gas boilers

doas-radiant
6
Charles E. and Mary Parente Life Sciences Building
100 Outdoor Air Applications and Ventilation
Standards

• 100 Outdoor Air Units will assure there to be no
  inter-space sharing of air
• This is done through the absence of a mix box
• Mixing is not allowed in lab spaces if it will
  transfer contaminants from space to space.
• 100 OA units use outdoor air to satisfy
  ventilation load and all of the thermal load

• In most cases the air required to relieve the
  entire thermal load on a space will surpass the
  amount of OA required for proper ventilation
• ASHRAE 62-2001 will list minimum suggested OA
  rates for a given occupancy
• Any amount of OA over the ASHRAE Std. is
  considered unvitiated or wasted in most cases
• Exception

doas-radiant
7
Charles E. and Mary Parente Life Sciences Building
100 Outdoor Air Applications and Ventilation
Standards
Bad
Good
Inter-space Recirculation
Intra-space Recirculation
doas-radiant
8
Charles E. and Mary Parente Life Sciences Building
Dedicated Outdoor Air Can Deliver!

• DOAS can bring in the minimal amount of outdoor
  air required (either by ASHRAE or for specific
  contaminant control) and pick up the rest of the
  thermal load with a parallel system.
• The use of a parallel system allows DOAS to
  supply at higher temperatures (in some cases)
  thus further reducing ventilation load and over
  all chiller size

Bad
Good
doas-radiant
9
Charles E. and Mary Parente Life Sciences Building
Redesign Concept
Comments

• Apply Dedicated Outdoor Air with parallel radiant
  cooling and heating to all labs, offices and
  classrooms
• Conventional constant air volume air handler for
  corridors and basement storage spaces
• Packaged units for stairwells as a method of
  smoke control
• Use of parallel radiant cooling and heating will
  reduce mixing contaminants within the room
• High induction low temp discharge for humidity
  control

• If we want to reduce the contaminant mixing
  throughout the air, why use high induction?
• Air mixes sooner, leaves contaminant buoyant in
  the breathable zone

doas-radiant
10
Charles E. and Mary Parente Life Sciences Building
Optimal Design Situation (Hybrid of Dilution
Ventilation and Local Exhaust
Hatching indicates negative pressure zones
created by exhaust. Each exhaust would be
located directly over the work station. Short
circuiting could be a problem.
doas-radiant
11
Charles E. and Mary Parente Life Sciences Building
Design Considerations and Procedures for
Dedicated Outdoor Air

• For this analysis the ventilator units will be
  sized to meet ASHRAE 62-2001 Standard. Heat
  recovery will be used.
• Radiant cooling panel surface temperature will be
  taken as 55F
• Ventilator unit will be designed to maintain
  space dewpoint less than 55F
• Indoor air quality assessment

doas-radiant
12
Charles E. and Mary Parente Life Sciences Building
Design Procedures for Dedicated Outdoor Air
(Classroom 101)
Cooling

• Space requires 600CFM OA by ASHRAE
• Space set point of 72F
• Space sensible load 22,588 Btu/hr
• Space latent load 4,800 Btu/hr
• DOAS supply point 45F DB and sat.

Given the above information we can determine
three key pieces of information DOAS sensible
Capacity 17,496 Btu/hr Radiant Panel Capacity
5,029 Btu/hr Resulting Dewpoint 52F
doas-radiant
13
Charles E. and Mary Parente Life Sciences Building
Design Procedures for Dedicated Outdoor Air
(Classroom 101)

• Panels rated for 55btu/(hrft2)
• Results in a panel area of 91ft2
• Ceiling coverage percentage of about 11

Why not supply at 52F and saturated?
The resulting dewpoint was derived by calculating
a humidity rise due to latent load. That
humidity rise is the same regardless of supply
air point. Supplying at 52 F and saturated will
result in a dewpoint above 55F.
doas-radiant
14
Charles E. and Mary Parente Life Sciences Building
Design Procedures for Dedicated Outdoor Air
(Classroom 101)
Heating

• Heating season is calculated in similar manner
• DOAS supply temperature of 80F was chosen
• Condensation control is not an issue with radiant
  heat
• Determine DOAS sensible capacity
• Determine radiant floor required capacity

doas-radiant
15
Charles E. and Mary Parente Life Sciences Building
Design Procedures for Dedicated Outdoor Air
(Classroom 101)
Radiant floor heating on step down (secondary
hydronic loop)
doas-radiant
16
Charles E. and Mary Parente Life Sciences Building
Design Conclusions for Dedicated Outdoor Air

• Overall thermally efficient
• A few instances of over cooling and over heating
• Those instances took place in storage (interior)
  areas
• Over cooling could be eliminated with the use of
  a sensible reheat wheel.
• By cooling the air to 45F and saturated and then
  sensibly reheating, we will maintain proper
  humidity ratio
• Over heating could be solved with the use of
  terminal reheat boxes. No over heating occurred
  in critical spaces (classrooms labs offices etc.)

doas-radiant
17
Charles E. and Mary Parente Life Sciences Building
Use of Heat Recovery (Enthalpy Type Only)

• By adding an enthalpy wheel we can further reduce
  cooling and heating loads
• Counter flow type wheel
• Cross contamination percent of .04
• Self purging for particulate matter
• Free pre-heating

doas-radiant
18
Charles E. and Mary Parente Life Sciences Building
Smoke Control Units for Stairwells (Creating a
Safe Haven)

• Positive pressure in stairwells
• Pressure difference of .5wg

doas-radiant
19
Charles E. and Mary Parente Life Sciences Building
Redesigned Plant Sizes
Existing Plant Sizes

• 116 Tons of Cooling
• 677.6 MBH of heating
• 300GPM Cooling Plant
• 70 GPM Heating Plant

• 210 Tons of Cooling
• 2,609 MBH of heating
• 517GPM Cooling Plant
• 240 GPM Heating Plant

doas-radiant
20
Charles E. and Mary Parente Life Sciences Building
Overall Reductions and Savings
Fan Reduction 23,336 CFM or 61.5
(.133/(cfmyr)) Cooling Plant Reduction 104
Tons or 47.3 (217.8/(tonyr)) Heating Plant
Reductions 1,931.3 MBH or 74 (54/(MBHyr)) Pump
ing Reductions 405 GPM or 52 (3.4/(Gpmyr))
At the rates given above (from HAP) we are
effectively making 130,960.05 per year with
DOAS-Radiant for our tested condition.
OR.
doas-radiant
21
Charles E. and Mary Parente Life Sciences Building
Overall Reductions and Savings
A brand new Porsche 911 Turbo every year and walk
home with 2760.05 change!
doas-radiant
22
Charles E. and Mary Parente Life Sciences Building
Reduction in on and off-site emissions
Existing
Redesigned
CO2 79,300 lb/yr SO2 486 lb/yr Nox 710
lb/yr CO 381 lb/yr Particulate 111 lb/yr
CO2 222,743 lb/yr SO2 1379.12 lb/yr Nox
2681.83 lb/yr CO 1683 lb/yr Particulate 493.144
lb/yr
doas-radiant
23
Charles E. and Mary Parente Life Sciences Building
Reduction in on and off-site emissions
Reduction
CO2 64.3 SO2 64.7 Nox 73.5 CO
77.3 Particulate 77.3
This building cleaned up quite nice
doas-radiant
24
Charles E. and Mary Parente Life Sciences Building
Indoor Air Quality Considerations
In lab type occupancies there is a good chance of
the presence of contamination sources
doas-radiant
25
Charles E. and Mary Parente Life Sciences Building
Indoor Air Quality Considerations

• Dilution Ventilation
• DOAS can be designed to bring in minimum outside
  air for IAQ
• Internal emissions need to be known
• Air testing required

doas-radiant
26
Charles E. and Mary Parente Life Sciences Building
Indoor Air Quality Considerations
Local Exhaust Ventilation

• High level contaminants
• Contaminants are immediately evacuated
• No mixing

doas-radiant
27
Charles E. and Mary Parente Life Sciences Building
Indoor Air Quality Considerations
Local Exhaust Ventilation

• DOAS may not supply enough make up air for
  exhaust units
• Short circuit hoods would work in conjunction
  with stair units
• Dampers would redirect all flow to stairwell when
  smoke detector trips

doas-radiant
28
Charles E. and Mary Parente Life Sciences Building
Redesign Conclusions

• DOAS with enthalpy wheel (as proposed)
• Correct with Sensible wheel
• Mild over heating
• Could work for IAQ if given proper information
• Large plant reductions
• Large Emission reductions
• Large cost savings (as compared with 100 OA
  application)

doas-radiant
29
Charles E. and Mary Parente Life Sciences Building
Payback Analysis (Breadth Work)
DOAS-Radiant initial cost 667,584 Pays Back in
3.7 Years (Under 25 of a 15 yr mechanical life
time) Payback period is taking into account 6
interest
doas-radiant
30
Charles E. and Mary Parente Life Sciences Building
Acoustical Analysis for Classroom 212 (Breadth
Work)
doas-radiant
31
Charles E. and Mary Parente Life Sciences Building
Acoustical Analysis for Classroom 212 (Breadth
Work)
Existing Conditions
Redesigned

• Resulting RC value 38
• Recommended RC 35-40
• Possible Vibrations

• Resulting RC value 33
• Recommended RC 35-40
• Possible Vibrations

Corrections
Corrections

• Acoustical Insulation
• 2 thick fiberglass (3lb/ft3)
• 5 coverage of common wall

• Acoustical Insulation
• 2 thick fiberglass (3lb/ft3)
• 40 coverage of common wall

doas-radiant
32
Charles E. and Mary Parente Life Sciences Building
Final Comments

• Switching 100 OA applications to DOAS
• If a space requires large amounts of OA DOAS can
  supply at higher temperatures and further reduce
  plant size
• Use of parallel system
• Global impact
• Cleaner Buildings
• Cleaner Environment

doas-radiant
33
Charles E. and Mary Parente Life Sciences Building
Acknowledgments
Tony Shebelock P.E.(Quad 3 Group) John Cowder
R.A. (Quad 3 Group) Joseph Ballz, Facilites
Manager (Kings College) Dr. William Groves Ph.D,
C.I.H. (Penn State University) Dr. Jae-Weon Jeong
PH.D, Advisor (Penn State University) AE
Mechanical Faculty Kyle Pepperman (Graphic
Design) Family and Friends
doas-radiant
34
Charles E. and Mary Parente Life Sciences Building
Questions
doas-radiant