PNW RTF -Rooftop Unit Working Group
- RTUG –
Rooftop Unit Research Project Phase 4
November 23, 2010
RTUG Agenda 112310
9:30am Introductions Agenda Review; RTUG Schedule Review
9:45 Review of Results from BPA RTU Pilot Research 2009-2010
RTU gas pack characterization from annual data
Model/methodology description
Examination of signature predicted annual usage with 3-4 weeks of metered data
Outside Air Temperature data sourcing
Points to meter
Sampling period
Recommended metering interval of 1 minute
M&V costs
Points included in the basic M&V package (kW and OAT)
Minimum requirements (temperature ranges/number of days) and reasons why
Questions to RTUG members:
What do members perceive as unknowns or gaps in this methodology and what is the process to address any gaps?
How does this protocol comport with the guidelines under development for Standardized Protocols with M&V?
Any other concerns small or large?
Next steps: Discuss recommendations to RTF [January 2011]; schedule additional RTUG review if needed
12:15-1:00pm Lunch
1:00 Status: Regional RTU Research Results Database: BPA and Web-Enabled T-Stat
http://www.nwcouncil.org/energy/rtf/subcommittees/rtug/Default.htm
1:05 Energy Trust of Oregon RTU DCV M&V – Dave Robison, Stellar Processes
1:25 CO2 Sensor Research– Reid Hart, PECI
1:45 BPA request for members to join new RTF Subcommittee on Variable Capacity (VC) Heat Pumps
2:05 Review draft elements of a regional RTU Strategic Plan/Roadmap including Research/Policy/Programs/Market
Transformation elements
3:30 Recap of meeting conclusions
4:00 Adjourn
Current RTUG Schedule
• Nov 23
• Follow up discussion if needed
• January 2011 RTF presentation
• RTF next steps with HVAC Committee
BPA RTU Winter Operation
Presented to:
RTUG
November 23, 2010
Presented by:
Kathryn Hile, The Cadmus Group
Howard Reichmuth, New Buildings Institute
Agenda Overview
• Project summary
• Proposed M&V protocol
• Data chunk analysis
• Outside air temperature
• Simplified monitoring
• Next steps
5
Annual Metering Summary
• Metered 45 units for one year
Reason
Site with old heat pumps, erratic operation
14
Unit operates in fan only mode (ventilation unit?)
or not at all in Summer 2010
4
Erratic data, possibly bad sensor
2
Too many days of sensor failure
+ 1_
Subtotal
Good data total
Total Units Metered
6
Count
21
+ 24
45
Annual Summary (cont.)
• Annual metering interval: one minute
• Costs
– Equipment: $1,150/RTU
– Metering equipment installation and removal:
$700/unit
– Analysis and reporting
7
M&V Protocol – Need Your Input
• Need your feedback, so we can have a high
consensus recommendation to RTF by February
• Will send out a draft protocol incorporating your
suggestions from today
• Would you support our recommendation to the
RTF on this protocol for a 90% confidence fan and
cooling energy savings?
8
Questions to Think About
• What are unknowns or gaps in this methodology
• How do we address any gaps?
• How does this protocol comport with the
guidelines under development for Standardized
Protocols with M&V?
• Any other concerns small or large?
9
Elements of the Protocol
• Energy signature analysis approach (Word doc)
• What points to meter
• Sampling period
– Number of days
– Temperature ranges
• Sample size
• Confidence interval and the distance ratio
10
Detailed Analysis for M&V Protocol
• Units selected based on consistent operation
(one mode)
– Gas packs
– Nine units
– Four on east side
– Five on west side
11
What Points to Meter?
• Use shortest possible measurement intervals to
avoid building changes
• Minimum required points to meter
– Outside air temperature
– Power
– Supply air temperature: nice, but not essential
12
Sampling Period
• Number of days – and why
• Temperature ranges – and why
– See range of temperatures for different points in
the monitoring season and different date ranges
– Frequency table with average daily data
– Economizer and compressor and fan operation
13
Updated Energy Signature
•
•
•
•
14
Based on linear regression fit
Fan and A/C savings
Annualized using TMY bin data
Tested quadratic regression fit, but no significant
improvement
Data Chunk Analysis
•
•
•
•
Basic ground rules
Statistics approach
Discussion of confidence intervals
What did we find?
15
Basic Ground Rules
• Units with constant operation (no switching
between fan auto/fan continuous in one RTU)
• 21 and 28 days of metered data, starting every 7th
day, mid-May through end of September
• Extrapolate to annual using regression
– Exclude all points with total daily kWh < (base load
* 10%)
16
Data Chunk Statistics Approach
• Applied to full annual estimate (including histogram)
• 90% confidence interval for each extrapolation
• Characterize temperature distributions with distance ratio:
(Average distance from each daily temp to mean cooling TMY temp)
(Variance among daily metering period temps)
• Number of observations for 28-day monitoring period
conservatively assumed to be only 21 days to account for
weekend mode
17
Confidence Intervals
• 90% confidence
• Overlapping CIs indicate no significant difference
• Distinct CIs (no overlap) indicate significant
difference
• Last summer’s savings loose estimate: 200
kWh/ton
• Savings estimate involves two precisions treated
in quadrature
18
What Did We Find?
• Accurate measurements require understanding site weather
and proper staging of metering
• Differences between hot east side metering and mild west
side metering
• Measurements at the 90% confidence can be achieved
• Buildings exhibit natural changes over a summer: ‘building
squirm’
• Best approach involves 4 weeks pre, 4 weeks post, with 3-4
week retrofit window
19
East Side Weather Summary
• Pasco weather from Pasco TMY3
• TMY3:
– Hourly values for a one-year period
– Derived from actual weather data 1991-2005
20
Pasco TMY3
Bin
30
35
40
45
50
55
60
65
70
75
80
85
Frequency
14
36
38
32
31
43
39
32
28
40
22
10
21
Pasco TMY3 365 Days
22
Pasco TMY3 May 1 – Sept 30
23
East Side Results Example 1
RTU Annual Energy
24,000
22,000
20,000
Annual Energy, kWh/yr
18,000
mean
16,000
lower 90%
upper 90%
1-May
1-Jun
1-Jul
14,000
12,000
10,000
1-Aug
1-Sep
8,000
6,000
4,000
2,000
0
40280
40300
40320
40340
40360
40380
40400
40420
40440
Julian day of monitoring start
24
Energy Signature
Energy, kWh/day
80
60
mode 1
40
Signature
mode 2
20
0
0
20
40
60
80
100
120
Avergae 24 hr temperature, deg F
Significant change, inadequate detailed data to diagnose.
25
East Side Results Example 2
RTU Annual Energy
12,000
Annual Energy, kWh/yr
10,000
mean
8,000
lower 90%
upper 90%
1-May
1-Jun
1-Jul
6,000
1-Aug
1-Sep
4,000
2,000
0
40280
40300
40320
40340
40360
40380
40400
40420
40440
Julian day of monitoring start
26
Energy Signature
Signature
Energy, kWh/day
80
60
Jun
Aug
Jul
40
20
0
0
10
20
30
40
50
60
70
80
90
100
Avergae 24 hr temperature, deg F
Small but significant change, 20% minimum OSA June to 50% OSA in August.
27
East Side Findings
• Best monitoring pre-late May, early June. Fourweek sample
• Best monitoring post-early August to end of
August
• Less accurate results for mid-summer, late
June/July monitoring interval
• Mid-summer data temperatures are above
economizer range leading to inaccurate
predictions
28
West Side Weather Summary
• Snohomish TMY3
Bin
30
35
40
45
50
55
60
65
70
75
80
85
Frequency
0
1
23
88
83
50
52
49
14
5
0
0
29
Snohomish TMY 365 Days
30
Snohomish TMY3 May 1 – Sept 30
31
West Side Results Example 1
RTU Annual Energy
10,000
9,000
Annual Energy, kWh/yr
8,000
7,000
mean
lower 90%
upper 90%
1-May
1-Jun
1-Jul
6,000
5,000
4,000
1-Aug
1-Sep
3,000
2,000
1,000
0
40280
40300
40320
40340
40360
40380
40400
40420
40440
Julian day of monitoring start
32
Energy Signature
Mode 1 signature
60
Energy, kWh/day
50
40
model
30
data
20
10
0
0
10
20
30
40
50
60
70
80
90
average 24 hr temperature, deg F
Messy data but leads to tight confidence interval. No significant change.
33
West Side Results Example 2
RTU Annual Energy
9,000
8,000
Annual Energy, kWh/yr
7,000
mean
6,000
lower 90%
upper 90%
1-May
1-Jun
1-Jul
5,000
4,000
1-Aug
1-Sep
3,000
2,000
1,000
0
40280
40300
40320
40340
40360
40380
40400
40420
40440
40460
Julian day of monitoring start
34
Energy Signature
Inspection Plot
Energy, kWh/day
60
40
June/jul
August
20
0
0
10
20
30
40
50
60
70
80
90
Avergae 24 hr temperature, deg F
Messy data. Early season heat and false cooling trigger. No significant change.
35
West Side Findings
• Good results at 90% confidence, but generally not
as good as east side
• Pre-retrofit period should start in June
• Post-retrofit period of four weeks should start in
August
Conclusion:
Meter four weeks pre and four weeks post to achieve
90% confidence
36
Sample Size
•
•
•
•
•
•
•
•
37
m
= sample size
= standard deviation of savings
= coefficient of variation among actual energy savings of units within program
= within the regression calculation for a given unit, the standard deviation of the
distance from the actual daily energy usage to the regression line
= savings over entire year
N = # compressor on days in TMY data – we can make this determination, based
on CZ
n = # compressor on days used in the analysis (should be all metered days in a
given operating mode, minus weekends if off on weekends)
R = distance ratio
Sample Size
• To get good estimates with 90% confidence, if
you service…
– 1,000 units, meter:
– 500 units, meter:
– 100 units, meter:
38
Outside Air Temperature
• Compared measured OAT to local weather station
data for all sites
– Average daily temperatures during cooling season
• Examples:
– Annualize using weather station data
– Annualize using metered OAT data
39
OAT Comparison Snohomish
40
OAT Comparison Snohomish
41
OAT Comparison Snohomish
42
OAT Comparison Pasco
43
OAT Comparison Pasco
44
OAT Comparison Pasco
45
Simplified Monitoring
• Weather station data may be key
• CT current/power measurement simplifies
installation?
• Potential metering costs can be reduced by 80%
46
Questions to RTUG
• What do members perceive as unknowns or gaps
in this methodology and what is the process to
address any gaps?
• How does this protocol comport with the
guidelines under development for Standardized
Protocols with M&V?
• Any other concerns small or large?
47
Next Steps in Research
• Draft M&V protocol for fan and A/C savings,
based on input from committee
– By December 1, we will send to RTUG committee
members a straw man of our recommendation
• Look at building characteristics to find a better
metric to predict energy savings
48
Regional RTU Research Results Database
http://www.nwcouncil.org/energy/rtf/subc
ommittees/rtug/Default.htm
• 102 RTUs 2009-10 BPA Pilot; 2wks-pre/2wks-post
• 25 RTUs 12 months monitored Sept/Nov/Jan 011
• Web-enabled T-stat: 2 sites, May-Sept 2010
Energy Trust of Oregon
Small Commercial HVAC Pilot Program
Stellar Processes
November 23, 2010
Small Commercial HVAC Pilot Program
Goal: test feasibility of specifying a standard repair treatment that can
be applied by contractors in a production mode in order to reduce
deployment costs. This pilot test was focused on Demand Controlled
Ventilation (DCV) as a strategy to save gas used for space heating.
Measure includes:
•Install a programmable thermostat or control system capable of
responding to CO2 controls.
•Set up proper scheduling and night setback.
•Ensure that economizers are connected with two-stage control wiring.
Install the new sensors that permit better economizer operation.
Properly set economizer changeover point.
•O&M as applicable: Repair noticeable air leaks around roof curbs.
Clean coils.
12/15/2009
ETO Small Commercial RTU
51
Demand Controlled Ventilation (DCV)
• Controls modulate the amount of makeup outside air
(OSA) based on the CO2 levels inside the facility. The
control system senses the level of CO2 and adjusts the
amount of outside air necessary to maintain a
minimum level of CO2.
• This procedure is expected to save space heating
energy since the excess outside air would otherwise
have to be conditioned.
• A well-designed cooling system would usually be
economizing in our climate, so no cooling savings are
expected.
12/15/2009
ETO Small Commercial RTU
52
Site Details
Office site -- attached warehouse was not treated.
12/15/2009
ETO Small Commercial RTU
53
Field Treatment
• Treated 15 of 21 air-handlers at the site. Of those,
10 units were actually monitored.
• All units were controlled with zone thermostats
(no central controls).
• Of 10 units tested, six had some degree of
malfunction with economizer operation. Typically,
enthalpy OSA sensors appeared to be out of
calibration. Units were four years old.
12/15/2009
ETO Small Commercial RTU
54
Damper Position Sensor
Position sensor reports damper displacement. Calibrated with measured
air flow using Energy Conservatory TrueFlow® system. Although both the
air flow and damper motion are non-linear, we found that the relationship
between air flow and position was surprisingly linear.
12/15/2009
ETO Small Commercial RTU
55
Example: Cooling Energy Signature
Although cooling was not the focus, the retrofit repaired some units that were not
properly economizing.
12/15/2009
ETO Small Commercial RTU
56
Summary of Change in OSA
Actual operation shows little agreement with design. Second floor offices were
expected to be lightly occupied but we found high occupancy. Some of these zones
were “flushing” and showed modest savings. %OSA reduced by 16% in monitored
units or estimated 14% overall.
12/15/2009
ETO Small Commercial RTU
57
Computed Energy Savings
Weather was mild during monitoring – no heating event occurred. Savings estimate
relied on calibrated engineering model to estimate annual performance.
12/15/2009
ETO Small Commercial RTU
58
Computed Energy Savings
Annual savings estimate 2320 therms or 11% works out to 0.08 therm/sf. Consistent
with regional modeling that has predicted a range of 0.02 to 0.09 therm/sf.
Base Case
With ECMs
Savings
% Saved
12/15/2009
Annual Energy
Consumption,
kWh
902,769
899,794
2,975
0.3%
Annual
Demand
kW per Month
39
40
-1
-3.5%
ETO Small Commercial RTU
Annual Energy
Consumption,
kWh
21,290
18,970
2,320
10.9%
59
Program Cost Effectiveness
Total Cost
NPV of Benefits
BCR
Lifetime
Levelized Cost, per therm
12/15/2009
ETO Small Commercial RTU
$11,159
$25,179
2.26
15
$0.379
60
Conclusions
• DCV successfully decreased the amount of outside ventilation air.
• Compute 11% gas savings or 2320 annual therms (0.08 therm per
sqft).
• Cost $11,159 for labor and materials. Benefit Cost Ratio 2.26
• Electricity savings were not significant. Since some of the units were
previously malfunctioning, there was a small increase in
compressor cooling energy as those units were brought back into
service. At the same time, there was an overall decrease in energy
used for ventilation.
• Recommended Follow-on Actions:
Confirm savings estimate with follow-up billing analysis.
Consider another verification of a similar project during the heating
season. ( no actual heating events occurred during this
monitoring).
12/15/2009
ETO Small Commercial RTU
61
RTU DCV Ventilation Issues
DCV Control Targets
DCV Analog vs.. Step Control
Carbon Dioxide Sensor Accuracy
Demand Controlled Ventilation (DCV)
• Idea here is to provide area rate when occupied,
then proportion people portion to actual
occupancy
• Measure occupancy by:
– Carbon dioxide (CO2) concentration
– Counters or security system
– Schedule approximation
– Camera technology
Target Is NOT 700 ppm!
• DCV CO2 concentration setpoint
– Earlier standard called for 700 ppm CO2 over ambient as
target level
– Ambient at 400 means 1100 ppm setpoint
• Actually is based on specific occupancy
• Explained well in the 62.1-2007 users manual
– Steady state CO2 CR
• Concentration lags occupancy
– DCV allowed to control for steady state
– Volume provides a buffer
– Pre-purge not required; may be good
• ~ 20 minutes “full” rate or one air change at occupancy
• Precede occupancy for high VOC spaces like retail
Find CR for your space
• CR is target CO2
–
–
–
–
Think OA% “area” & “full”, not minimum
Met varies due to activity
Large ratio indicates more DCV savings
Use actual people & CFM, not defaults!
Rp
Area Type
Art Classroom
Office - default
Office - open
Class (age 9+)
Retail Sales
Grocery
Call Center
Lecture Class
Restaurant
Conference
Assembly
Pz
20
5
7
35
15
8
12
65
70
50
150
sf/p
50
200
143
29
67
125
83
15
14
20
7
met
1.2
1.2
1.2
1.2
1.5
1.7
1.2
1.2
1.4
1.2
1.2
Rs
cfm/p cfm/sf
10
5
5
10
7.5
7.5
5
7.5
5
5
5
0.18
0.06
0.06
0.12
0.12
0.06
0.06
0.06
0.18
0.06
0.06
CR
ppm
824
874
994
1001
1050
1162
1206
1357
1643
1701
1893
*For all types: area is 1000 square feet, COa = 400 ppm, Ez is 80%, unit cfm 1.0 cfm/sf
OA% OA%
area
full Ratio
23% 48% 2.1
8% 11% 1.4
8% 12% 1.6
15% 59% 3.9
15% 29% 1.9
8% 15% 2.0
8% 15% 2.0
8% 68% 9.1
23% 66% 2.9
8% 39% 5.2
8% 101% 13.5
DCV: Step vs. Analog Control
• Step control:
– “full %” at CR or concentration target (volume buffers need)
– “area %” @ 20%-40% below CR
• Analog control recommended by 62.1 User Manual
– Area rate at 400 ppm
– Area + people (full) rate at CR target ppm
– Note difference in DCV
damper
position
vs. OSA%
Ventilation
Sequence
OSA
Set Area & Full Positions based on OSA% measurements
40%
OApos
30%
OSA%
OAareaPos
@ 400
20%
OAfullPos
@ AQset
10%
0%
0
500
1000
Space/Return CO2 PPM
1500
2000
CO2 Transmitter Accuracy
Bin Occurance (Bars)
35%
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
30%
25%
20%
15%
10%
5%
0%
5%
10%
15%
20%
25%
30%
35%
Line is % of Units with
Worse Accuracy
CO2 Transmitter Error @ 1100 ppm
40%
+/- error
Source: National Building Controls Information Program. PTR. Iowa EC & CEC. June 2009.
Source:
http://www.energy.iastate.edu/
Efficiency/Commercial/
download_nbcip/PTR_CO2.pdf
NBCIP/ Iowa Energy
Center Testing
No manufacturers had all three samples within specs!
• Count on being within 200 ppm, usually high
• Many sensors saturate above 1700 ppm
• Self calibrating sensors improve persistence
Closer Look at Accuracy Impact
CO2 Transmitter Error @ 1100 ppm
10
42.5%
37.5%
32.5%
27.5%
22.5%
17.5%
12.5%
7.5%
2.5%
0.0%
-2.5%
-7.5%
-12.5%
0
-17.5%
5
-22.5%
Frequency n=45
15
error boundary
Source: National Building Controls Information
Program. PTR. Iowa EC & CEC. June 2009.
Eliminating 3 of 13 manufacturers
keeps error within +/- 21%
• Sensors are generally high; (mean = + 12%)
• Relative accuracy will maintain with self-calibration
• Particular manufacturers are at extremes
Phase 4 NBI – RTUG Work Plan
• Convene/manage the RTUG for the RTF
• Actively promote collaboration within/outside the
region on EM&V protocols, RTU efficiency research
• Review BPA research results and assist in drafting the
proposed annualized savings methodology
• Assist in implementing the Regional RTU Research
Results database – RRRR or R4 database
• Lead the RTUG through a process to scope technical
and related elements of a regional RTU Strategic Plan
• Identify options for equipment redesign, deeper
retrofit and early replacement
Where Are We Going and Why?
• WHAT ARE WE DOING STRATEGICALLY?
• Research to support EE resource acquisition only?
• Technical understanding/information through testing/measurementfield& laboratory
• Elements of a SP: facts, allies, good internal communications, silo
busting.
• Data repository, communication mechanism, leading edge tech
• Increased market knowledge
• Local capacity to do testing of new equipment/components
• Connections with market allies, EE organizations
national/regional/state, various CA org relationships
• Facilitate communication market transformation among parties; get
performance feedback in a variety of ways
RTU Strategic Plan Elements
• Technical Assessment
• Programmatic
• Market Transformation
• Advocacy/Collaboration
PNW RTU Strategic Map/Road Plan
• Elements of an Strategic Plan for Rooftop Unit Efficiency
Development
– Goal setting
– Leading to deemed savings estimator tool and field EM&V
protocol
– Technology improvement
– Audience: PNW regional and local, public and investor-owned
energy utility planners, utility EE program
designers/implementers, public benefits energy efficiency
organizations, the HVAC industry including contractors and
equipment OEM’s
– Deliverable: Information/substantiation of the kWh/kW savings
potential from new and existing rooftop unit HVAC equipment.
– Communications
– Good information/data/analysis
Technical Assessment
RTF to maintain functional data repository with open access. Add appropriate data
sets and analytical results as available from Avista, Idaho Power, Premium Ventilation
Project, Pacific Northwest National Laboratory, BPA Web-enabled thermostat project,
and others in and outside the region
• Develop a research scope/budget for establishing and extending a low cost
monitoring protocol on a set of RTUs for up to 60 months. Candidates should
chosen through operating RTU service programs
– Track persistence of performance for all components; track maintenance costs
– Whole building conditions and operating changes substantially documented
– Active customer/HVAC contractor contact with education/training for both groups
•
•
•
•
•
•
•
Develop a research scope/budget to establish RTU measure life values
Reconciliation between modeling and metered result inputs to modeling
Whole building data analysis
Lower cost RTU field monitoring
Premium Ventilation Package: Near-Term + Extended Function Testing and Analysis
Economizer research program including DCV interaction
Test of web-based RTU control and performance monitoring to determine impact
on building operator schedule management using the monitoring information
• Improve DOE2/eQUEST RTU calculations
RTF RTU Challenges
• Minimum air flow:
- technical: field measurement & service protocol
- building code requirement
- program protocol
- program benefit-cost issue
• Measure life: 6th Plan = 18yrs comp/5 yrs O&M
• Operating (measure/system?) persistence: ?
Assessment Criteria
• Consistency with goals regional power/conservation
plan including resource acquisition and cost
effectiveness
• Efficiency potential kWh/kW/therms
• Technology advancement, RDD&Deployment
• Operating performance management
• O&M&R cost management/Cost of Ownership
• GHG management
• Market response
• Market transformation opportunity
• Integrated design/optimization
• EM&V requirements/potential
PNW Energy Efficiency Technology Roadmap-1
• RD1. Heat recovery optimization routines such that
economizer performance is not impacted
• RD2. Better MTBF information for equipment to inform
predictive maintenance programs and controls
• RD3. More reliable fault detection (FDD) and diagnostics
controls at smaller scale, market
• RD4. More research on neural networks and artificial
intelligence to help inform design of self-healing and
learning HVAC controls systems would be useful
• RD5. Software development to have fully-functional selfdiagnosing controls
• RD6. BPA RTU now testing simple fault detection and
diagnostics sequences on RTUs
• RD7. Make ECM motors bigger, add belt drives
PNW Energy Efficiency Technology Roadmap-2
• RD8. Research to reduce maintenance with WCEC, NIST, ETO
• RD9. Drop-in ECM motors for residential, need furnaces, case
studies, savings, etc. - Concept 3?
• RD10. ACRx Sentinel by CEC PIER field study: up-to-date?
• RD11. Reliability of enthalpy controls – underway
• RD12. Condensing gas – pack RTU: NRCAN, CEE
• RD13. Develop load based lab testing for RTUs (ASHRAE 1608RTAR).
• RD14. Fault response on compressors related to US companies
• RD20. Do field tests to provide feedback in order to help develop
more accurate building simulation
• RD21. Field M&V test for zoning savings to gather data for
optimizing design choices for zoning with different heating and
cooling systems
Programmatic
Additional Measures
• Add economizers
• Controls: Premium Vent Package, other?
• Demand Controlled Ventilation (DCV)
• FDD/performance monitoring
• ECM/VSD
• Gear-driven economizer actuators [increasing market share]
• Airflow/ventilation including outside air damper issue
• Other?
New RTU products: Lennox Energence, H80 Hybrid RTU, Ductless/VRF
Early RTU Retirement: What is the size of the regional benefit?
Market Transformation
– Customer education
– HVAC contractor/distributor education/training
– Quality Installation/Quality Maintenance standards
PNW RTU Future
• Research: how long, how deep?
• Future RTU program design –existing & new units
• Technology advancement
• West Coast Regional Collaboration: coop RTU
research/cost-sharing + advocacy
• National advocacy with HVAC OEM’s
Collaboration/Advocacy
• Advanced Rooftop Unit (CA PIER + 3ET)
• Publish performance curves
• Snap disc replacement
• Outside air sensor enclosure/placement
• Climate optimized RTU standards
• RTU FDD w/remote comm - CA Title 24
Advocacy/Collaboration-2
CA T24 RTU FDD Strawman
Low airflow
Low/High refrigerant charge
Sensor failed
Compressor short cycling
Economizer not functional/optimized
Performance degradation
Non-occupied operation
Remote communications gateway
Collaborate/Communicate/Educate
• RTUG:
http://www.nwcouncil.org/energy/rtf/studies/ongoing/rtug/Defaul
t.htm
• BPA E3 ET/R&D:
http://www.bpa.gov/energy/n/emerging_technology/index.cfm
• NEEA ET:
http://www.nwalliance.org/participate/submit_your_idea.aspx
• CA ETCC: http://www.etcc-ca.com/
• Western Cooling Efficiency Center: http://wcec.ucdavis.edu/
• Western HVAC Performance Alliance: www.performancealliance.org
• State Energy Offices
• Integrated Design Labs
• US DOE –National Labs