functional performance: tools, rigor and collaboration · functional performance: tools, rigor and...
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Functional Performance: Tools, Rigor and Collaboration
David Sellers, Senior EngineerFacility Dynamics Engineering
21st National Conference on Building Commissioning
AIA Quality Assurance
The Building Commissioning Association is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.
This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.
Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
21st NCBC Conference
Presentation Description
This presentation uses a case study format to explore functional testing in an existing building commissioning process. Specifically, a functional test is developed to assess the thermal flywheel potential of a small chilled water system. The results are then used to develop control system program modifications that allow a short cycling problem to be resolved while still providing the required environmental conditions inside the facility.
21st NCBC Conference
At the end of this session, participants will be able to:
1. Understand the difference between a functional testing process in an existing building commissioning environment vs. a new construction environment
2. Understand that there can be a hierarchy to a functional testing process
3. Understand the key elements associated with developing a functional test
4. Understand how functional testing can be used as a diagnostic tool in an existing building commissioning process
5. Understand how a functional test can be used to gather useful data in an existing building commissioning process
Learning Objectives
21st NCBC Conference
The Path to Selecting Equipment and Systems
Operating Requirements
Heat Transfer Equipment Selections
Process Parameters
System Configuration
Owner’s Project
Requirements
Distribution Equipment Selections
Installation Documents
Assembled Building
Physical Configuration
Loads
Construction Project
FUNCTIONAL TESTING IN EXISTING BUILDINGS 5
The New Construction Perspective on Functional Testing
Operating Requirements
Heat Transfer Equipment Selections
Process Parameters
System Configuration
Owner’s Project
Requirements
Distribution Equipment Selections
Installation Documents
Assembled Building
Physical Configuration
Loads
Construction Project
FUNCTIONAL TESTING IN EXISTING BUILDINGS 6
Generally speaking, successful completion of everything inside the red dotted line is required for system acceptance
Testing Hierarchy;More than Balancing Man Power
Commission Supporting
Utility Systems
Verify Prestart Checks & Startups
Verify Control Wiring and Calibration
Verify Control Programming
Complete Equipment
Safety Testing
Component Factory Startups
Component Startups
Sub‐assembly Factory Startups
Sub‐assembly Startups
Verify Safeties with Prime
Mover Off‐line
Start‐up Prime Mover (Pump,
Fan, etc.)
Test Component Controls
Test System Level Control Functionality
Test Building Level Control Functionality
Begin Normal Operations
Run Trend Analysis; Fine Tune Systems
Seasonal and Warranty Testing
Begin Ongoing Cx
Component Level Testing
System Level Testing
Each utility system can have a testing hierarchy that is similar to this, much of which must be complete before the supporting system can be tested
7
Generally speaking, successful completion of everything inside the red dotted line is required for system acceptance
Testing Hierarchy;More than Balancing Man Power
Commission Supporting
Utility Systems
Verify Prestart Checks & Startups
Verify Control Wiring and Calibration
Verify Control Programming
Complete Equipment
Safety Testing
Component Factory Startups
Component Startups
Sub‐assembly Factory Startups
Sub‐assembly Startups
Verify Safeties with Prime
Mover Off‐line
Start‐up Prime Mover (Pump,
Fan, etc.)
Test Component Controls
Test System Level Control Functionality
Test Building Level Control Functionality
Begin Normal Operations
Run Trend Analysis; Fine Tune Systems
Seasonal and Warranty Testing
Begin Ongoing Cx
Component Level Testing
System Level Testing
Each utility system can have a testing hierarchy that is similar to this, much of which must be complete before the supporting system can be tested
8
Mostly Forced Response Testing
Generally speaking, successful completion of everything inside the red dotted line is required for system acceptance
Testing Hierarchy;More than Balancing Man Power
Commission Supporting
Utility Systems
Verify Prestart Checks & Startups
Verify Control Wiring and Calibration
Verify Control Programming
Complete Equipment
Safety Testing
Component Factory Startups
Component Startups
Sub‐assembly Factory Startups
Sub‐assembly Startups
Verify Safeties with Prime
Mover Off‐line
Start‐up Prime Mover (Pump,
Fan, etc.)
Test Component Controls
Test System Level Control Functionality
Test Building Level Control Functionality
Begin Normal Operations
Run Trend Analysis; Fine Tune Systems
Seasonal and Warranty Testing
Begin Ongoing Cx
Component Level Testing
System Level Testing
Each utility system can have a testing hierarchy that is similar to this, much of which must be complete before the supporting system can be tested
9
Mostly Forced Response Testing
Transition to Natural Response Testing
Generally speaking, successful completion of everything inside the red dotted line is required for system acceptance
Testing Hierarchy;More than Balancing Man Power
Commission Supporting
Utility Systems
Verify Prestart Checks & Startups
Verify Control Wiring and Calibration
Verify Control Programming
Complete Equipment
Safety Testing
Component Factory Startups
Component Startups
Sub‐assembly Factory Startups
Sub‐assembly Startups
Verify Safeties with Prime
Mover Off‐line
Start‐up Prime Mover (Pump,
Fan, etc.)
Test Component Controls
Test System Level Control Functionality
Test Building Level Control Functionality
Begin Normal Operations
Run Trend Analysis; Fine Tune Systems
Seasonal and Warranty Testing
Begin Ongoing Cx
Component Level Testing
System Level Testing
Each utility system can have a testing hierarchy that is similar to this, much of which must be complete before the supporting system can be tested
10
Mostly Forced Response Testing
Transition to Natural Response Testing
Mostly Natural Response Testing
The Existing Building Perspective on Functional Testing
Operating Requirements
Heat Transfer Equipment Selections
Process Parameters
System Configuration
Owner’s Project
Requirements
Distribution Equipment Selections
Installation Documents
Assembled Building
Physical Configuration
Loads
Construction Project
FUNCTIONAL TESTING IN EXISTING BUILDINGS 11
The Existing Building Perspective on Functional Testing
Operating Requirements
Heat Transfer Equipment Selections
Process Parameters
System Configuration
Owner’s Project
Requirements
Distribution Equipment Selections
Installation Documents
Assembled Building
Physical Configuration
Loads
Construction Project
FUNCTIONAL TESTING IN EXISTING BUILDINGS 12
New Construction versus EBCx Testing
New Construction• Trying to prove design intent
• Demonstrate all elements of the system meet requirements
• Verification and quality assurance process
EBCx• Trying to understand design
intent• Focused on certain elements
of the system • Diagnostic and troubleshooting
process
FUNCTIONAL TESTING IN EXISTING BUILDINGS 13
Le Conte Hall
• UC Berkeley Physics Department Home
• 148,000 square feet• Four floors plus basement‒ Floors 1 and 2 - Classrooms
and research‒ Floors 3 and 4 - Offices, class
rooms, informal meeting space
• Interconnected with other physics department buildings
• MBCx program participant since 2009
• MBCx Best Practices Award winner for the 2009 program cycle
FUNCTIONAL TESTING IN EXISTING BUILDINGS 14
Le Conte Hall
• UC Berkeley Physics Department Home
• 148,000 square feet• Four floors plus basement‒ Floors 1 and 2 - Classrooms
and research‒ Floors 3 and 4 - Offices, class
rooms, informal meeting space
• Interconnected with other physics department buildings
• MBCx program participant since 2009
• MBCx Best Practices Award winner for the 2009 program cycle
It Takes a Team to SucceedLeft to Right
Anthony Vitan, Eleanor Crump, Julia Gee, Chuck Frost
FUNCTIONAL TESTING IN EXISTING BUILDINGS 15
Le Conte Hall
• UC Berkeley Physics Department Home
• 148,000 square feet• Four floors plus basement‒ Floors 1 and 2 - Classrooms
and research‒ Floors 3 and 4 - Offices, class
rooms, informal meeting space
• Interconnected with other physics department buildings
• MBCx program participant since 2009
• MBCx Best Practices Award winner for the 2009 program cycle
It Takes a Team to SucceedLeft to Right
Ancestors of David Sellers, Mark Porter, Ron Simens, Gary Kawabuchi and Mark Arney test a
new ideaFUNCTIONAL TESTING IN EXISTING BUILDINGS 16
2004 – 2007 Renovation– Seismic issues– Deferred maintenance– Reconfiguration– Restoration– MEP Update
FUNCTIONAL TESTING IN EXISTING BUILDINGS 17
HVAC Equipment40,000 cfm constant volume reheat, 100% outdoor air AHU for 1st and 2nd floor (basement location)
Exhaust fans associated with AHU 1
FUNCTIONAL TESTING IN EXISTING BUILDINGS 18
HVAC Equipment32,000 cfm constant volume reheat, economizer equipped AHU for 3rd and 4th floor
FUNCTIONAL TESTING IN EXISTING BUILDINGS 19
HVAC EquipmentSteam fired variable flow heating hot water system (basement location)
FUNCTIONAL TESTING IN EXISTING BUILDINGS 20
HVAC EquipmentAir cooled constant volume chilled water system
FUNCTIONAL TESTING IN EXISTING BUILDINGS 21
A Bit More Information on the Chilled Water System• 2 – 50 ton compressors• Compressors can unload to 25% of capacity• Compressors equipped with hot gas bypass• Relatively short piping circuit
FUNCTIONAL TESTING IN EXISTING BUILDINGS 22
Small Load + Large (Relatively) Chiller = Potential Problem
Internal Load, No Outdoor Air Cooling, 1‐5 Tons Maximum
100 Ton Chiller
Visit www.Av8rdas.wordpress.com for a larger copy of the system diagram; Link located on the right side of the home page under 03 – Materials from Classes and Presentations
FUNCTIONAL TESTING IN EXISTING BUILDINGS 23
100% Outdoor Air Load
Economizer Equipped Load
Large temperature supply temperature swings potentially a problem in terms of maintaining the desired conditions at the load
FUNCTIONAL TESTING IN EXISTING BUILDINGS 24
Five to six compressor cycles per hour or more; a.k.a “short cycling”
FUNCTIONAL TESTING IN EXISTING BUILDINGS 25
The Problem with Short Cycling
FUNCTIONAL TESTING IN EXISTING BUILDINGS 26
Unresolved short cycling cost impacts‒ Less than optimal temperature control
• IEQ issues in hot and humid climates• Product quality issues• Ripple effects (other control processes become
unstable‒ Premature compressor or motor failure
• Unscheduled outage• Unscheduled cost - $20,000 - $40,000 each for
the 50 ton compressors on this project
The Problem with Short Cycling
FUNCTIONAL TESTING IN EXISTING BUILDINGS 27
The Research Load is Not the Only Small Load
100% Outdoor Air Load
Economizer Equipped Load
100 Ton Chiller
FUNCTIONAL TESTING IN EXISTING BUILDINGS 28
Non-integrated vs. Integrated
• Cooling coil load • Q = 4.5 x cfm x ∆h• Q = 4.5 x 30,000 x (25.4 –
22.8)• Q = 351,0000 Btu/hr• Q = 29.3 tons
• Cooling coil load • Q = 4.5 x cfm x ∆h• Q = 4.5 x 30,000 x (22.8 –
22.6)• Q = 27,0000 Btu/hr• Q = 2.3 tons
FUNCTIONAL TESTING IN EXISTING BUILDINGS 29
Non-integrated vs. Integrated
• Space Conditions• Space temperature = 72°F• Space RH = 50%• Space enthalpy = 26.4 Btu/lb
• Space Load (average cooling coil leaving conditions)
• Q = 4.5 x cfm x ∆h• Q = 4.5 x 30,000 x (26.4–
22.7)• Q = 499,500 Btu/hr• Q = 41.6 tons
FUNCTIONAL TESTING IN EXISTING BUILDINGS 30
Non-integrated vs. Integrated
LOADS
Space Coil – Non-Integrated Coil – IntegratedEconomizer Economizer
41.6 tons 29.3 tons 2.3 tons
FUNCTIONAL TESTING IN EXISTING BUILDINGS 31
Dealing with Short Cycling
• Infinite Capacity Modulation‒ No refrigeration compressor
can modulate over an infinite range on its own• Technology dependent
(reciprocating vs. centrifugal vs. scroll vs. screw vs. absorption)
• System dependent‒ Size of the piping
network‒ Relative sizes of the
prime movers
• False load‒ Serve a recirculating
constant volume reheat load
‒ Hot gas bypass
FUNCTIONAL TESTING IN EXISTING BUILDINGS 32
Dealing with Short Cycling
• Infinite Capacity Modulation‒ No refrigeration compressor
can modulate over an infinite range on its own• Technology dependent
(reciprocating vs. centrifugal vs. scroll vs. screw vs. absorption)
• System dependent‒ Size of the piping
network‒ Relative sizes of the
prime movers
• False load‒ Serve a recirculating
constant volume reheat load
‒ Hot gas bypass
FUNCTIONAL TESTING IN EXISTING BUILDINGS 33
Dealing with Short Cycling
• Infinite Capacity Modulation‒ No refrigeration compressor
can modulate over an infinite range on its own• Technology dependent
(reciprocating vs. centrifugal vs. scroll vs. screw vs. absorption)
• System dependent‒ Size of the piping
network‒ Relative sizes of the
prime movers
• False load‒ Serve a recirculating
constant volume reheat load
‒ Hot gas bypass• Lengthen the compressor run
cycles and off cycles‒ Anti-recycle timer‒ Thermal flywheels
FUNCTIONAL TESTING IN EXISTING BUILDINGS 34
Dealing with Short Cycling
• Infinite Capacity Modulation‒ No refrigeration compressor
can modulate over an infinite range on its own• Technology dependent
(reciprocating vs. centrifugal vs. scroll vs. screw vs. absorption)
• System dependent‒ Size of the piping
network‒ Relative sizes of the
prime movers
• False load‒ Serve a recirculating
constant volume reheat load
‒ Hot gas bypass• Lengthen the compressor run
cycles and off cycles‒ Anti-recycle timer‒ Thermal flywheels
FUNCTIONAL TESTING IN EXISTING BUILDINGS 35
Here’s a Question
How much of a thermal flywheel does the existing piping system represent?
FUNCTIONAL TESTING IN EXISTING BUILDINGS 36
Who Knows the Answer?
… the Building KnowsFUNCTIONAL TESTING IN EXISTING BUILDINGS 37
How Do We Ask The Building About It?
• We perform a functional test• Functional test components
‒ Statement of purpose‒ Instructions for using the
test form‒ Equipment requirements‒ Acceptance criteria‒ Precautions‒ Documentation‒ Procedure‒ Return to Normal and
Follow-upVisit www.Av8rdas.wordpress.com for a copy of the test; Link located on the right side of the home page under 03 – Materials from Classes and Presentations
FUNCTIONAL TESTING IN EXISTING BUILDINGS 38
Start With A Statement of Purpose
General Guidelines• Target the effort• Goal of the test• Underlying assumptions• Desired outcome‒ Tie to acceptance criteria
Our Statement of Purpose• Assess the thermal flywheel
represented by the existing piping system‒ Determine the minimum and
maximum chilled water temperatures that can be tolerated
‒ Quantify the thermal flywheel in terms of ton-hours
FUNCTIONAL TESTING IN EXISTING BUILDINGS 39
Test Form Instructions
General Guidelines• How should results be
documented?‒ Pass‒ Fail‒ Intermediate information‒ Comments
• Date and time stamps• Initials
Be clear; words have different meanings to different people
FUNCTIONAL TESTING IN EXISTING BUILDINGS 40
Test Form Instructions
General Guidelines• How should results be
documented?‒ Pass‒ Fail‒ Intermediate information‒ Comments
• Date and time stamps• Initials
Our Instructions• Review the procedure prior to
testing• Document the results in the
CACEA commissioning tool• Review decisions to deviate
from the plan with the team and note changes
• If the test is suspended prior to completion, run through the return to normal procedure
FUNCTIONAL TESTING IN EXISTING BUILDINGS 41
Required Equipment
General Guidelines• Standard tool set• Special tools‒ Unusual measurement
requirement‒ Critical accuracy requirement‒ Expediency
FUNCTIONAL TESTING IN EXISTING BUILDINGS 42
Required Equipment
General Guidelines• Standard tool set• Special tools‒ Unusual measurement
requirement‒ Critical accuracy requirement‒ Expediency
Our Equipment• Standard tool set
FUNCTIONAL TESTING IN EXISTING BUILDINGS 43
Acceptance Criteria
General Guidelines• Tied directly to the test’s stated
goals‒ Measured parameters‒ Documented conditions
• Clear and unambiguous terms• Special documentation
requirements‒ Picture‒ Witness signature‒ Control system report‒ Trend data
“Wait! Wait! Cancel that … I guess it says ‘helf.’”
FUNCTIONAL TESTING IN EXISTING BUILDINGS 44
Acceptance Criteria
General Guidelines• Tied directly to the test’s stated
goals‒ Measured parameters‒ Documented conditions
• Clear and unambiguous terms• Special documentation
requirements‒ Picture‒ Witness signature‒ Control system report‒ Trend data
Our Acceptance Criteria• Information only test; There
are no acceptance criteria‒ Acceptance criteria are less
common for EBCx testing‒ A similar test in a new
construction process may have acceptance criteria
FUNCTIONAL TESTING IN EXISTING BUILDINGS 45
Precautions
General Guidelines• Safety concerns
‒ Protection‒ Comfort level
• Risk management‒ Operational risks
• Cost vs. benefit• Likelihood of the problem
‒ Equipment damage‒ Temporary over-rides
HERMAN
“Arnold, will you please stand away from that on/off switch”
FUNCTIONAL TESTING IN EXISTING BUILDINGS 46
Precautions
General Guidelines• Safety concerns
‒ Protection‒ Comfort level
• Risk management‒ Operational risks
• Cost vs. benefit• Likelihood of the problem
‒ Equipment damage‒ Temporary over-rides
Our Precautions• Be careful working around
rotating machinery• Remember that there are other
things connected to the system, directly and indirectly when manipulating system parameters
• Exercise caution when driving chilled water temperatures to lower than normal ranges
FUNCTIONAL TESTING IN EXISTING BUILDINGS 47
Documentation
General Guidelines• What do you need to support
the test?‒ Submittals‒ Performance data‒ System diagrams‒ Calibration data‒ Factory start-up data
• What do you need to capture before starting?‒ Nameplate data‒ As found conditions
Our Documentation• Supporting information
‒ Located on the project web portal
‒ System diagram‒ Mechanical drawings‒ Control sequences ‒ Control shop drawings ‒ O&M information and
equipment submittal data• Capture before starting
‒ Current set points‒ Lab operating criteria
FUNCTIONAL TESTING IN EXISTING BUILDINGS 48
Prerequisites
General Guidelines• Conditions necessary to test
‒ Weather‒ Operating mode
• System readiness• People required for testing
‒ Owner‒ Contractor/Technicians‒ Code official‒ Factory representative
• Some items may tie back to precautions
Our Prerequisites• Low load condition required• Research and other building
functions can tolerate loss of chilled water
• Verify staff buy-in/available:‒ Lab‒ Building/campus
management‒ Physical plant
FUNCTIONAL TESTING IN EXISTING BUILDINGS 49
Preparation
General Guidelines• Team members in position
‒ Rehearsal• Monitoring equipment
‒ In position‒ Activated‒ Calibrated
• Coordinated with building functions
• As found conditions documented
FUNCTIONAL TESTING IN EXISTING BUILDINGS 50
Preparation
General Guidelines• Team members in position
‒ Rehearsal• Monitoring equipment
‒ In position‒ Activated‒ Calibrated
• Coordinated with building functions
• As found conditions documented
Our Preparation• Verify system flow rate has
been documented via pump test
• Verify logging is working for critical parameters
FUNCTIONAL TESTING IN EXISTING BUILDINGS 51
The Procedure
General Guidelines• Thinking it through ahead of
time is important• Be clear
20.
l
Perform a shut off test to verify the pump
Proceed as follows:and documenting the pump differential pressures.size by briefly closing the discharge valve and
Requirement DataInclude units Initials, Date
and Time
Completed
20.
Pump discharge pressureReturn discharge valve to original position.
Pump suction pressure
Document discharge valve positionStart the second pump to prevent a chiller safety shut down due to loss of flow.
document:Briefly close the discharge valve and
Perform a shut off test to verify the pump
Proceed as follows:and documenting the pump differential pressures.size by briefly closing the discharge valve and
Requirement DataInclude units Initials, Date
and Time
Completed
20.
l
Perform a shut off test to verify the pump
Proceed as follows:and documenting the pump differential pressures.size by briefly closing the discharge valve and
Requirement DataInclude units Initials, Date
and Time
Completed
FUNCTIONAL TESTING IN EXISTING BUILDINGS 52
The Procedure
General Guidelines• Thinking it through ahead of
time is important• Be clear• Include cross-references
‒ Multiple indications of results‒ Take more data than you
need
Our Procedure• Run the supply water
temperature as far down as possible with out nuisance safety trips
• Monitor the zone temperatures‒ When researchers indicate
they are concerned:• Document the cycle time• Document the chilled
water temperature• Run the chilled water
temperature back down and document the run cycle time
Visit www.Av8rdas.wordpress.com for a copy of the test; Link located on the right side of the home page under 03 – Materials from Classes and Presentations
FUNCTIONAL TESTING IN EXISTING BUILDINGS 53
Return To Normal and Follow up
General Guidelines• Don’t take off for home as soon as
you’ve finished the test!‒ Release manual over-rides‒ Return set points to normal‒ Wait to make sure things are
working properly!
FUNCTIONAL TESTING IN EXISTING BUILDINGS 54
Return To Normal and Follow up
General Guidelines• Don’t take off for home as soon as
you’ve finished the test!‒ Release manual over-rides‒ Return set points to normal‒ Wait to make sure things are
working properly!• Did all go as planned?
‒ Does the data make sense?‒ Is it telling you something that
requires immediate action?‒ Are your documentation needs
covered?• Issue preliminary reports
FUNCTIONAL TESTING IN EXISTING BUILDINGS 55
Return To Normal and Follow up
General Guidelines• Don’t take off for home as soon as
you’ve finished the test!‒ Release manual over-rides‒ Return set points to normal‒ Wait to make sure things are
working properly!• Did all go as planned?
‒ Does the data make sense?‒ Is it telling you something that
requires immediate action?‒ Are your documentation needs
covered?• Issue preliminary reports
Our Return to Normal• Release any manual over rides
and return set points to normal settings
• Retrieve and save trend data• Document the results on the web
portal• Notify contractors and UCB of any
issues that were discovered
FUNCTIONAL TESTING IN EXISTING BUILDINGS 56
Our Results
Trend data shows colder temperature than local indication during the “charge” cycle
Lab and building functions can handle an upper limit of 59°F for the flywheel
A 2 hour flywheel representing about 13 ton‐hours is
possible
It will take one compressor about 10 minutes to recharge the flywheel
FUNCTIONAL TESTING IN EXISTING BUILDINGS 57
Automating Our Results
FUNCTIONAL TESTING IN EXISTING BUILDINGS 58
Opportunity 1 - Captured
FUNCTIONAL TESTING IN EXISTING BUILDINGS 59
Opportunity 2 - Identified
Whole building meter data indicates that the compressors tend to run at full load any time they run
FUNCTIONAL TESTING IN EXISTING BUILDINGS 60
Logger Data Confirms Suspicions
FUNCTIONAL TESTING IN EXISTING BUILDINGS 61
Unnecessary Hot Gas = Unrealized Savings
Good News• Flywheel cycle captures
26,900 kWh/$2,690 of savings via the MBCx project‒ Testing performed as part of
the general MBCx effort‒ Programming modified “on
the fly”• Additional savings potential
justifies a factory service call‒ Perform routine checks and
maintenance‒ Optimize set points‒ Optimize controls
Bad News• 11,404 kWh/$1,140 of savings
“left on the table
Visit www.Av8rdas.wordpress.com for the complete story
FUNCTIONAL TESTING IN EXISTING BUILDINGS 62
The Bottom Line A Warm, Low Occupancy DayAbout 10 minutes on and
90 minutes off with only the lab load
1‐1/2 to 2 cycles per hour with the lab and lightly loaded AHU
Compressor capacity limited during the charge cycle
FUNCTIONAL TESTING IN EXISTING BUILDINGS 63
The Bottom Line A Warm, Low Occupancy Day
FUNCTIONAL TESTING IN EXISTING BUILDINGS 64
The Bottom Line A Warm, NormalOccupancy Day
System exits the flywheel cycle when conditions warrant normal operation
Unloading system “captures” the load and runs the compressor steady‐state against it
FUNCTIONAL TESTING IN EXISTING BUILDINGS 65
The Bottom Line A Warm, NormalOccupancy Day
Second compressor comes on line to supplement the lead compressor and also matches capacity to requirements
Lag compressor takes over as lead and continues to match the load with out short cycling
FUNCTIONAL TESTING IN EXISTING BUILDINGS 66
The Bottom Line A Warm, NormalOccupancy Day
Temperature swings are moderated compared to the pattern prior to the service call
FUNCTIONAL TESTING IN EXISTING BUILDINGS 67
How Can the Functional Testing Guide Help?
FUNCTIONAL TESTING IN EXISTING BUILDINGS 68
THANK YOUDavid Sellers, Senior Engineer Facility Dynamics Engineering NW Satellite OfficeDSellers@Facility Dynamics.comOffice: (503) 286-1494Cell: (503) 320-2630www.FacilityDynamics.comTechnical blog on WordPress at Av8rdas.Wordpress.com
SUPPLEMENTAL INFORMATIONIntegrated vs. Non-Integrated Economizer Operation
Non-Integrated is Different from Integrated
T
58°F Set Point
FUNCTIONAL TESTING IN EXISTING BUILDINGS 71
T
Non-Integrated
58°F Set Point
57°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 72
T
Non-Integrated
58°F Set Point
58°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 73
T
Non-Integrated
58°F Set Point
59°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 74
BAROMETRIC PRESSURE: 29.921 in. HGATMOSPHERIC PRESSURE: 14.696 psia
ALTITUDE: SEA LEVEL
0 5 10 15 20 25
30
35
40
45
50
50
55
55
ENTHALPY - BTU PER POUND OF DRY AIR
0
5
10
15
20
25
30
35
40
45
ENTHALP
Y - BTU P
ER POUND O
F DRY A
IR
SATURATION TE
MPERATURE - °
F
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
-5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
105
110
115
120
DR
Y B
ULB
TE
MP
ER
ATU
RE
- °F
.001
.002
.003
.004
.005
.006
.007
.008
.009
.010
.011
.012
.013
.014
.015
.016
.017
.018
.019
.020
.021
.022
.023
.024
.025
15%
25%
2%
4%
6%
8% RELATIVE HUMIDITY
10
20
30
40
50
6070
8090
-50
05
510
10
15
15
20
20
25
25
30
30
35
35
40
40
45
45
50
50
55
55
60
60
65
65
70
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75
75
80
8085
HU
MID
ITY
RA
TIO
- P
OU
ND
S M
OIS
TUR
E P
ER
PO
UN
D D
RY
AIR
0
1.0 1.0
-
2.04.08.0-8.0-4.0-2.0-1.0-0.5
-0.4-0.3-0.2-0.1
0.10.20.3
0.40.5
0.6
0.8
-2000-1000
0
500
1000
1500
2000
3000
5000
-
SENSIBLE HEAT QsTOTAL HEAT Qt
ENTHALPYHUMIDITY RATIO
hW
Space
Outdoor Air Mixed Air at MOA
Cooling Coil Discharge
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
BAROMETRIC PRESSURE: 29.921 in. HGATMOSPHERIC PRESSURE: 14.696 psia
ALTITUDE: SEA LEVEL
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
Visit www.Av8rdas.wordpress.com for a Resource List with links to free coil modeling software; Link from the right side of the opening page under 01 –Commissioning Resources
FUNCTIONAL TESTING IN EXISTING BUILDINGS 75
T
Integrated
58°F Set Point
57°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 76
T
Integrated
58°F Set Point
58°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 77
T
Integrated
58°F Set Point
59°F
FUNCTIONAL TESTING IN EXISTING BUILDINGS 78
BAROMETRIC PRESSURE: 29.921 in. HGATMOSPHERIC PRESSURE: 14.696 psia
ALTITUDE: SEA LEVEL
0 5 10 15 20 25
30
35
40
45
50
50
55
55
ENTHALPY - BTU PER POUND OF DRY AIR
0
5
10
15
20
25
30
35
40
45
ENTHALP
Y - BTU P
ER POUND O
F DRY A
IR
SATURATION TE
MPERATURE - °
F
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
-5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
105
110
115
120
DR
Y B
ULB
TE
MP
ER
ATU
RE
- °F
.001
.002
.003
.004
.005
.006
.007
.008
.009
.010
.011
.012
.013
.014
.015
.016
.017
.018
.019
.020
.021
.022
.023
.024
.025
15%
25%
2%
4%
6%
8% RELATIVE HUMIDITY
10
20
30
40
50
6070
8090
-50
05
510
10
15
15
20
20
25
25
30
30
35
35
40
40
45
45
50
50
55
55
60
60
65
65
70
70
75
75
80
8085
HU
MID
ITY
RA
TIO
- P
OU
ND
S M
OIS
TUR
E P
ER
PO
UN
D D
RY
AIR
0
1.0 1.0
-
2.04.08.0-8.0-4.0-2.0-1.0-0.5
-0.4-0.3-0.2-0.1
0.10.20.3
0.40.5
0.6
0.8
-2000-1000
0
500
1000
1500
2000
3000
5000
-
SENSIBLE HEAT QsTOTAL HEAT Qt
ENTHALPYHUMIDITY RATIO
hW
Space
Outdoor Air
Cooling Coil Discharge
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
BAROMETRIC PRESSURE: 29.921 in. HGATMOSPHERIC PRESSURE: 14.696 psia
ALTITUDE: SEA LEVEL
Chart by: AKTON PSYCHROMETRICS, www.aktonassoc.com
FUNCTIONAL TESTING IN EXISTING BUILDINGS 79