Continuous Commissioning® Assessment Report · 2011-11-21 · Experiment Station (TEES) under contract to Sandia National Laboratory ... Of the boxes, 112 are parallel fan powered

Retro-Commissioning Plan

for the

Jack E. Brown Chemical Engineering Building

(Bldg. 0386)

Submitted to:

Office of Energy Management

Physical Plant Department

Texas A&M University

Prepared by:

Energy Systems Laboratory

December 10, 2008

ii

EXECUTIVE SUMMARY

A Retro-Commissioning (RC) assessment was conducted at the Jack E. Brown Chemical Engineering

Building (0386#) after it was identified as a good candidate for RC during the pre-retro-commissioning

phase. The Jack E. Brown Chemical Engineering Building is a seven-story building with a total

conditioned area of 205,000 square feet consisting of laboratories, classrooms, offices, and server rooms.

It is located on the main campus of the Texas A&M University in College Station, Texas. The HVAC

system consists of 37 Air Handling Units (AHUs) with a total design maximum supply flow of 393,600

cfm, including 23 single duct variable air volume (SDVAV) AHUs, 13 single duct single zone (SDSZ)

AHUs, and 1 multi-zone constant air volume (MZCAV) AHU. The building exhaust system is

comprised of 33 exhaust fans. The major exhaust system in the building is for the lab tracking system.

The building HVAC system is DDC controlled and powered by the Siemens Apogee system.

The purpose of the assessment was to further identify comfort and energy efficiency improvement

opportunities in this building especially focusing on its HVAC system. Basic building information has

been collected and field investigations have been conducted at selected AHUs and terminal boxes. This

report documents the resultant findings and recommendations.

Retro-Commissioning (RC) Opportunities:

1. Implement OCC/UN-OCC schedule and optimize the ventilation rate for lab areas

2. Implement cold deck temperature setpoint reset for all VAV AHUs and MZCAV A34

3. Implement OCC/UN-OCC schedule on the AHUs serving non-lab areas

4. Implement static pressure setpoint reset for all VAV AHUs

5. Optimize the temperature and humidity control for the SDSZ AHUs

6. Optimize the min flow setting and day/night mode control for fan power boxes

7. Implement space temperature dead band control for lab areas

8. Improve OA damper control if applicable

9. Optimize preheat temperature setpoint if applicable

10. Improve the differential pressure (DP) setpoint reset control for the ChW and HHW pumping

systems

Maintenance Opportunities

1. Verify and calibrate flow stations, CO2 sensors, room temperature sensors, and other control points.

2. Check and adjust HHW manual valves as needed.

3. Perform necessary maintenance on the filters and valves for all AHUs and boxes.

The baseline Energy Use Index (EUI) was 432.8 kBtu/ft2/year and the Energy Cost Index (ECI) was

$8.8730/ft2/year. It is estimated that implementation of the RC process would result in the energy

savings of 6,700 MMBtu/yr in ChW, 4,200 MMBtu/yr in HHW, and 182,600 kWh/yr in electricity, for

an estimated annual energy cost savings of $190,000. The cost savings was based on a rate of

$14.775/MMBtu for ChW, $17.374/MMBtu for HHW, and $0.117/kWh for electricity. The total cost of

implementing the RC process is roughly estimated at $80,000, making it a 0.4 years simple payback.

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ACKNOWLEDGEMENTS

The retro-commissioning (RC) initial assessment process detailed in this report was performed by the

Energy Systems Laboratory (ESL) under the direction of, and with the assistance of the Office of

Energy Management (OEM) at Texas A&M University. For information concerning OEM, please contact

Homer L. Bruner, Jr. at (979) 862-2794. For additional information regarding the information in this report

or the overall Continuous Commissioning® program at ESL, please contact Song Deng at (979) 862-1234.

The lead RC investigator for this building was Cory Toole, EIT.

iv

DISCLAIMER

This report was prepared by the Energy Systems Laboratory (ESL) of the Texas Engineering

Experiment Station (TEES) under contract to Sandia National Laboratory. Neither the ESL or TEES or

any of their employees, makes any warranty, express or implied, or assumes any legal liability or

responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or

process disclosed, or represents that its use would not infringe on privately-owned rights.

Reference herein to any specific commercial product, process or service by trade name, trademark,

manufacturer or otherwise, does not necessarily constitute or imply its endorsement, recommendation or

favoring by the ESL or TEES or any agency thereof. The views and opinions of the authors expressed

herein do not necessarily state or reflect those of the ESL or TEES or any agency thereof.

v

TABLE OF CONTENTS

EXECUTIVE SUMMARY ........................................................................................................................ ii

ACKNOWLEDGEMENTS ....................................................................................................................... iii

DISCLAIMER ........................................................................................................................................... iv

TABLE OF CONTENTS .............................................................................................................................v

LIST OF FIGURES .................................................................................................................................. vii

LIST OF TABLES .................................................................................................................................... vii

BACKGROUND .........................................................................................................................................1

SITE DESCRIPTION ..................................................................................................................................1

General Facility Description ....................................................................................................................1

General HVAC System Description ........................................................................................................2

PERFORMANCE BASELINES .................................................................................................................4

Energy Baseline .......................................................................................................................................4

Indoor Environment Baseline ..................................................................................................................7

Building Pressurization ............................................................................................................................9

FINDINGS AND OPPORTUNITTIES .......................................................................................................9

Pumping System ....................................................................................................................................10

Air-Handling Units ................................................................................................................................11

Terminal Boxes ......................................................................................................................................16

Exhaust System ......................................................................................................................................18

Lighting System .....................................................................................................................................19

CONCLUSIONS........................................................................................................................................19

APPENDIX A: As-Built Design Information............................................................................................21

APPENDIX B: Field Measurement Records .............................................................................................24

vi

vii

LIST OF FIGURES

Figure 1. Jack E. Brown Chemical Building ............................................................................................. 1

Figure 2. Building location. ....................................................................................................................... 1

Figure 3. Room layout for floor 3/4/5/6/7 .................................................................................................. 2

Figure 4. Time series for Jack E. Brown Chemical Building (#0386) ....................................................... 5

Figure 5. Electricity vs. outside air dry-bulb temperature .......................................................................... 6

Figure 6. Chilled water vs. outside air dry-bulb temperature ..................................................................... 6

Figure 7. Hot water vs. outside air dry-bulb temperature ........................................................................... 7

Figure 8. Indoor thermal environment baseline in PMV chart ................................................................... 9

Figure 9. HHW pumping system control .................................................................................................. 11

Figure 10. AHU system setup ................................................................................................................... 12

Figure 11. AHU1-1 OA damper operation ............................................................................................... 14

Figure 12. AHU4-3 preheat temperature control ...................................................................................... 15

Figure 13. Terminal box serving the server room..................................................................................... 16

Figure 14. Current min/max flow settings for fan powered boxes ........................................................... 17

Figure 15. Lab tracking system ................................................................................................................. 18

LIST OF TABLES

Table 1. Room function for each floor........................................................................................................ 2

Table 2. Summary of Annual Energy Use, based on the Baseline Period .................................................. 7

Table 3. Indoor environment baseline measurements................................................................................ 8

Table 4. List of RC measures with estimated savings and priority .......................................................... 10

Table 5. Savings estimated for electricity, ChW and HHW ..................................................................... 20

1

BACKGROUND

The Energy Systems Laboratory has been under contract with the Physical Plant at Texas A&M

University since 1997 to perform retro-commissioning on selected campus buildings. This process

involves a systematic study of building performance to identify cost effective methods to improve

safety, comfort, and energy efficiency within the building. During the time period since this began,

more than 70 buildings have been commissioned, resulting in millions of dollars of energy savings to

Texas A&M University.

The Jack E. Brown Chemical Engineering Building was selected as a potential building for retro-

commissioning. An initial assessment was conducted in October 2008, and results suggested that this

building would be a good candidate for retro-commissioning. A more in-depth assessment was then

performed to further identify potential areas for building improvement. The results of this assessment

are presented in this report.

SITE DESCRIPTION

General Facility Description

Figure 1. Jack E. Brown Chemical Building Figure 2. Building location.

The Jack E. Brown Chemical Engineering Building was constructed in 2004 and is located on the main

campus of the Texas A&M University in College Station, Texas. The building has seven floors with a

total conditioned area of 205,000 square feet and consists primarily of laboratories, and offices and

classroom. The major room function for each floor is listed in Table 1 and the room layout for the 3rd

floor to the 7th

floor is shown in Figure 3 . It is generally occupied on weekdays from 7:30 AM to 5:30

PM, but also has some occupancy later in the evening and on weekends.

2

Figure 3. Room layout for floor 3/4/5/6/7

Table 1. Room function for each floor

Floor # Major function

1 Classrooms, computer and study rooms

2 Chemical Engineering offices

3/4/6 Chemical labs (interior) and office (exterior)

5 BL2 labs (interior) and office (exterior)

7 Clean rooms(interior) and offices (exterior)

General HVAC System Description

Mechanical

The chilled water (ChW) system in the building utilizes two identical pumps, each 125 hp and supplying

3,000 gpm, serving the main building and one small pump serving the server rooms, with VFDs under

EMCS control. The building piping system is of the variable flow type with two-way piping. The

heating hot water (HHW) system in the building utilizes two identical pumps, each 50 hp and supplying

1,070 gpm, with VFDs under EMCS control. A summary of the building pumping information is shown

in Table A - 1 in the Appendix.

The HVAC system in the building consists of 37 AHUs with a total design maximum supply flow of

393,600 cfm, including 23 SDVAV AHUs, 13 SDSZ AHUs, and 1 MZCAV AHU. Among the 23 VAV

AHUs, 9 AHUs are 100% outside air units (OAHUs) with a total design outside air flow of 157,125 cfm.

Table A - 2 in the Appendix provides an overview of the AHUs in the building, with their design

information. The building contains 240 terminal boxes with DDC control. Of the boxes, 112 are parallel

fan powered boxes, 25 are series fan powered boxes, 57 are in-line variable air volume reheat boxes

serving the labs, and 46 are variable air volume boxes without fan and reheat. The building exhaust

system is comprised of 40 exhaust fans without VFD and 2 exhaust fans with VFDs. The total design

maximum exhaust flow is about 212,960 cfm. Table A - 23 in the Appendix provides an overview of the

Laboratories

3

exhaust fans in the building, with their design information. The major exhaust system in the building is

for the lab tracking system.

Controls

The building HVAC system is DDC controlled and powered by the Siemens Apogee system.

At the time of the RCP investigation, the ChW and HHW pumps were run using the lead/lag control

scheme. The ChW/HHW pumping and the related building return valves were controlled to maintain the

minimum of three end loop differential pressures (DP) at its setpoint. The ChW end loop DP setpoint

was reset to maintain the ChW valves of AHU712 and AHU713 between 80%-90% open. The HHW

end loop DP setpoint was reset to maintain the secondary HHW return temperature between 120°F -

130°F. The small server ChW pumping system was controlled to maintain the DP of the end server loop

at 5 psi.

All AHUs ran 24/7 continuously. The ChW valves for the SDVAV AHUs were controlled to

maintain the cold deck temperature at constant set points from 53°F-56°F, whereas the pre-heat

valves were controlled to maintain the hot deck temperature at constant set points from 50°F -

56°F. The set points are shown in Table A - 3 Exhaust Fans Design Information

MARK Design CFM SP INCH WC MOTOR HP

EF-1-1 3,500 1.5 2

EF-1-2 6,200 1.75 5

EF-1-3 4,920 0.7 1 1/2

EF-1-4 1,200 1.5 3/4

EF-4-1 1,330 2.25 1

EF-4-2 785 3.75 1 1/2

EF-4-3 2,100 3.75 2

EF-4-4 1,330 2.25 1

EF-4-5 1,330 2.25 1

EF-4-6 1,380 2.5 1 1/2

EF-4-7 785 3.75 1 1/2

EF-4-8 1,330 2.25 1

EF-4-9 8,500 4 10

EF-4-10 8,500 4.25 15

EF-4-11 8,500 4.25 15

EF-4-12 880 0.625 1/4

EF-4-13 9,000 3.5 15

EF-5-1 8,500 4 10

EF-5-2 8,500 4 10

EF-5-3 8,500 4 10

EF-5-4 8,500 4 10

EF-5-5 785 3.75 1 1/2

EF-6-1 8,500 3.75 10

4

EF-6-2 9,750 3.75 15

EF-6-3 8,500 4 10

EF-6-4 11,000 3.75 15

EF-6-5 9,800 3.5 10

EF-7-1 3,500 2.5 3

EF-7-2 5,900 3.75 7 1/2

EF-7-3 4,035 2.5 3

EF-7-4 440 0.35 1/8

EF-7-5 7,200 2.75 7 1/2

EF-7-6 4,400 3.25 5

EF-7-7 2,665 2.25 2

EF-7-8 750 0.75 1/4

GRH-1 2,710 0.04 -

GRH-2 2,710 0.04 -

SFP-1 5,000 1 3

SFP-2 5,000 1 3

OAI-1 6,745 0.1 -

EF-3-1 9,000 4.6 15

EF-3-2 9,000 4.6 15

Total 212,960 241

Table A - 4. The supply fan speeds for SDVAV AHUs were modulated to maintain the static pressure at

constant set points, which could be from 0.75 inch WC to 3.50 inch WC. The outside air dampers for the

majority of non-OAHU VAV units were modulated to maintain the design OA flow whereas the outside

air dampers for AHU1-1 and AHU1-2 were modulated to maintain the maximum room CO2 level at

1,000 ppm.

The ChW and HHW control valves for most of SDSZ AHUs serving the 7th

floor were couple controlled

to maintain the space temperature at 67°F when the associated space relative humidity was less than

50%. When the space relative humidity was higher than 55%, the ChW control valves were controlled to

maintain the cold deck temperature at 53°F and the HHW control valves were controlled to maintain the

space temperature at their set points. The ChW control valves for MZCAV were modulated to maintain

the cold deck temperature at a constant set point of 53°F and the HHW control valves were controlled to

maintain the space temperature at 72°F.

The lab tracking system was controlled to maintain a negative pressure relative to the hallway by using

the offset flow method. The offset flow set points for most of the labs were overridden at 152 cfm.

PERFORMANCE BASELINES

Energy Baseline

The baseline period chosen was from 9/1/2007 through 8/31/2008. Figure 4 shows the outside air dry-

bulb temperature and the time series plots for the consumptions of Electricity, CHW, and HHW using

5

daily data. Figure 5 - Figure 7 show the consumption as it relates to the average daily outdoor dry bulb

temperature during the baseline period.

Figure 4. Time series for Jack E. Brown Chemical Building (#0386)

6

Figure 5. Electricity vs. outside air dry-bulb temperature

Figure 6. Chilled water vs. outside air dry-bulb temperature

7

Figure 7. Hot water vs. outside air dry-bulb temperature

It was found that from the HHW chart that there was about 25 MMBtu/day of reheat in the building

even during very hot outdoor air temperatures. While a laboratory building may require more reheat

than a typical office or classroom building because of larger ventilation requirements, the consumption

levels still indicate some potential for HHW savings through improvements in control and maintenance.

The baseline energy usage for the building is summarized in Table 2. The baseline Energy Use Index

was 432.8 kBtu/ft2/yr and the Energy Cost Index (ECI) was $8.873 /ft2/year. The annual energy cost

was $1,818,970.

Table 2. Summary of Annual Energy Use, based on the Baseline Period

Annual Use Unit Cost Energy Cost Baseline Period

ELE 34.7479 (kWh/ft2/yr) 0.117 ($/kWh) 4.0655 ($/ft2/yr) 9/1/07 to 8/31/08

CHW 250.8 (kBtu/ft2/yr) 14.775 ($/MMBtu) 3.7062 ($/ft2/yr) 9/1/07 to 8/31/08

HHW 63.4 (kBtu/ft2/yr) 17.374 ($/MMBtu) 1.1014 ($/ft2/yr) 9/1/07 to 8/31/08

Indoor Environment Baseline

Indoor Environment measurements, including dry-bulb and black ball temperatures, relative humidity,

and CO2 level, were taken at various locations throughout the building on Oct 23, 2008. At the time of

measurement, the outside air temperature was about 59°F-62°F and the relative humidity was about

37%-44%. The measurement results are shown in Table 3. Based on the results, a thermal comfort

evaluation was conducted by using the predicted mean vote (PMV) index method. The PMV index

8

predicts the mean response of a large group of people according to the ASHRAE thermal sensation scale

from -3 (cold) to +3 (hot).

The thermal comfort indexes based on the PMV method revealed that most of the sample points (13 out

of 16) were within acceptable thermal condition (-0.5<PMV<0.5), as shown in Figure 8. 3 points fell

outside the acceptable thermal condition but still were close to the acceptable boundary. In addition,

based on the conversation with the building proctor, hot/cold complaints were received in some rooms,

which would be addressed as a part of final retro-commissioning. The spot check results also showed

that all of CO2 levels were below 600 ppm, which indicated the potential of reducing OA intake in non-

lab areas.

Table 3. Indoor environment baseline measurements

Room # Room Function

Dry Bulb

Temperature

(ºF)

Relative

Humidity

(%)

Mean Radiant

Temperature

(ºF)

PMV* CO2

(ppm)

100 Floor Lobby 71.3 38.9% 69.88 -0.580 525

254 Office 72.3 38.5% 71.73 -0.385 550

200 Floor Hallway 70.8 37.9% 71.65 -0.504 505

200A

(Near stairs) Floor Hallway 74.9 33.6% 74.76

-0.021 515

330 Lab 75.1 32.7% 75.10 0.011 480

335 Office 71.1 37.0% 71.95 -0.467 475

341 Office 72.1 35.3% 72.38 -0.375 533

400

(Near Zachry) Floor Hallway 70.3 31.5% 82.98

0.167 425

413 Office 73 33.7% 73.28 -0.259 506

206 Lab 71.8 30.7% 72.22 -0.435 430

500


0.518 450

532 Office 72.7 33.7% 73.55 -0.262 585

529 Lab 71.6 31.1% 72.87 -0.403 460

600


-0.495 490

630 Lab 73.1 30.3% 73.66 -0.246 470

626 Office 71.1 33.5% 73.08 -0.412 550

Notes: *The PMV calculation was based on the assumptions below:

Metabolic rate: 1.2met

Clothing level: 0.70clo

Air velocity: 20fpm

9

Figure 8. Indoor thermal environment baseline in PMV chart

Building Pressurization

Pressure measurements were conducted to determine the baseline building pressurization relative to the

outside on Oct 24, 2008. The measurements were taken at the front and the back entrances of the

building. The measurement results showed that the building was positively pressurized relative to the

outside at the two entrances. The front entrance pressurization relative to the outside was about +0.020

inch water column and the back entrance pressurization relative to the outside was about +0.016 inch

water column, which were acceptable building pressurization values.

FINDINGS AND OPPORTUNITTIES

Since the building was built in 2004, the overall condition of the HVAC equipment was good. However,

a number of potential control problems and opportunities in the building were discovered. The major RC

opportunities are summarized in Table 4, with their priorities. The priorities are based on their potential

benefit as well as ease of implementation.

It is estimated that implementation of all of the RC measures would save approximately $190,000 per

year, based on utility rates of $14.775/MMBtu for ChW, $17.374/MMBtu for HHW, and $0.117/kWh

for electricity. The cost of implementing the retro-commissioning process is roughly estimated at

$80,000, for a simple payback period of around 0.4 years. The brief description and explanations of the

RC opportunities developed for each subsystem during the RCP phase are provided following the table.

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Pre

dic

ted

Mea

n V

ote

(P

MV

)

Measured Points

Cold

Hot

Comfort Zone

10

Table 4. List of RC measures with estimated savings and priority

Priority

# Sub-system Brief RC Measure Description

Est. Savings

($/yr)

1 Exhaust &

Terminal Box

Implement OCC/UN-OCC schedule and optimize the

ventilation rate for lab areas $ 50,000

2 AHU Implement cold deck temperature setpoint reset for all

VAV AHUs and MZCAV A34 $ 48,000

3 AHU Implement OCC/UN-OCC schedule on the AHUs

serving non-lab areas $ 15,000

4 AHU Implement static pressure setpoint reset for all VAV

AHUs $ 14,000

5 AHU Optimize the temperature and humidity control for the

SDSZ AHUs $ 13,000

6 Terminal Box Optimize the min flow setting and day/night mode

control for fan power boxes $ 13,000

7 Terminal Box Implement space temperature dead band control for lab

areas $ 13,000

8 AHU Improve OA damper control if applicable $ 11,000

9 AHU Optimize preheat temperature setpoint if applicable $ 6,000

10 Pumping Improve the DP setpoint reset control for the ChW and

HHW pumping systems $ 4,500

Pumping System

ChW system

The ChW system in the building utilizes two identical ChW pumps, with VFDs under EMCS control,

and operates on a lead/lag schedule. The ChW pumping and the related building return valve were

controlled to maintain the minimum of three end loop DPs at its setpoint. The ChW end loop DP

setpoint was reset from 6 psi to 20 psi to maintain the ChW valves of AHU712 and AHU713 between

80%-90% open.

It was found that the ChW DP setpoint was reset at the lower limit (6 psi); in the meanwhile, the ChW

valves of AHU712 and AHU713 were less than 70% open in Oct 13, 2008. It indicates the possibility of

improving the secondary DP setpoint reset control.

It is estimated that this measure would result in energy savings of 13,000 kWh/yr in electricity, for an

estimated annual cost savings of $1,500.

11

HHW system

The HHW system in the building utilizes two identical HHW pumps, with VFDs under EMCS control,

and operates on a lead/lag schedule. The HHW pumping and the related building return valve was

controlled to maintain the minimum of three end loop DPs at its setpoint. The HHW end loop DP

setpoint was reset from 10 psi to 20 psi to maintain the secondary HHW return temperature between

120°F -130°F.

It was found that all of the hot water manual valves for the AHUs and reheat boxes were partially open

and the HHW DP setpoint was reset at 20 psi at the time of investigation, as shown in Figure 9. Since

the DP sensors were almost at the loop end, and normally the design DP for AHU HHW coil was less

than 4 psi, it was unnecessary to provide as high as 20 psi DP at the end loop. This indicates the

potential of improving the secondary DP setpoint reset control. In addition, the HHW manual valve

being partial-open indicates the possibility for HHW loop balancing optimization.



Figure 9. HHW pumping system control

Air-Handling Units

The HVAC system in the building consists of 37 AHUs, including 9 VAV OAHUs, 14 SDVAV AHUs,

13 SDSZ AHUs, and 1 multi-zone CAV AHU. Based on the design, about 80% of outside air flow for

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the OAHUs serves the interior labs directly and the rest of outside air flow is supplied to other AHUs

serving other non-lab areas. The AHU system setup is shown in

Figure 10.

Figure 10. AHU system setup

During the initial assessment process, air-side and water-side measurements were performed on 6 AHUs

(2 VAV OAHU, 3 SDVAV AHU and 1 multi-zone CAV AHU). Measurement results are shown in

Appendix B. The existing control strategies for all of the AHUs were reviewed. The major potential

problems and opportunities are as follows:

1) Implement cold deck temperature setpoint reset for all VAV AHUs and MZCAV A34

The ChW control valves for all of the VAV AHUs (including 9 OAHUs) and MZCAV A34 were

controlled to maintain the cold deck temperature at constant set points ranging from 53°F-56°F. The

constant cold deck set points, as shown in Table A - 4, could cause unnecessary simultaneous cooling

and heating.

It is recommended that an optimal reset schedule be implemented for the cold deck temperature set

points. For instance, an optimal reset schedule based on a combination of dew point and reheat valve

positions could be implemented for the OAHUs and a reset schedule based on reheat valve positions

could be implemented for the non-OAHUs.

It is estimated that this measure would result in energy savings of 1,510 MMBtu/yr in ChW and 1,510

MMBtu/yr in HHW, for an estimated annual cost savings of $48,000.

2) Implement OCC/UN-OCC schedule on the AHUs serving non-lab areas

At the time of the RCP investigation, all AHUs, even the AHUs serving non-lab areas, i.e. offices and

classrooms, run 24/7 continuously. Typically, it is not necessary for the AHUs serving non-lab areas to

run continuously and a kind of shutdown/setback schedule could be implemented on these AHUs.

It is recommended that the room’s function, schedule, and thermal requirement be further investigated as

a part of final retro-commissioning. As one consideration, an OCC/UN-OCC schedule based on the

combination of the terminal boxes day/night mode and time schedule could be implemented on the

AHUs serving non-lab areas.

OAHU SDVAV

Lab terminal box

Non-lab SDVAV

13

It is estimated that this measure would result in energy savings of 860 MMBtu/yr in ChW, 200

MMBtu/yr in HHW, and -6,000 kWh/yr in electricity. Despite the electricity penalty from high fan

speeds at startup, it is estimated that this measure will result in a cost savings of $15,000 per year.

3) Implement static pressure setpoint reset for all VAV AHUs

The supply fan speeds for all VAV AHUs were modulated to maintain the static pressure at the

associated constant setpoint separately. The static pressure set points at the time of the RCP

investigation are shown in Table A - 4. It was found that some constant static pressure set points were

set as high as 3.5 inch WC, which was close to the maximum safe operation pressure for typical AHU

ducts. The high static constant pressure set points also could cause the terminal box dampers always

partially closed, which was proved by the fact that all terminal box dampers for AHU1-1 and AHU1-2

were less than 70% open in Oct 21, 2008. The partial damper positions indicated unnecessarily high

static pressure set points. It is recommended that a demand-based static pressure set point reset schedule

be considered to save fan energy consumption.



4) Optimize the temperature and humidity control for the SDSZ AHUs

All the SDSZ AHUs in this building serve the clean room in the 7th

floor. Based on the existing control

programming, the ChW and HHW control valves for most of SDSZ AHUs serving the 7th

floor were

couple controlled to maintain the space temperature at 67 °F when the associated space relative humidity

was less than 50%. When the space relative humidity was higher than 55%, the ChW control valves

were controlled to maintain the cold deck temperature at 53 °F and the HHW control valves were

controlled to maintain the space temperature at 67 °F.

It seems that the existing control programming intends to dehumidify the space air by controlling the

cold deck temperature at 53°F. However, the related dew point temperature is only about 50°F when the

space temperature and relative humidity are 67 °F and 55% separately. This indicates the potential of

optimizing the relative humidity set point. In addition, the hard constant temperature setpoint indicates

the possibility of optimizing temperature control by implementing temperature dead band schedule. It is

recommended that a survey of thermal environment requirement for the clean rooms be conducted to

determine the optimal set points.

It is estimated that this measure would result in energy savings of 410 MMBtu/yr in ChW and 410


5) Improve OA damper control if applicable

Based on the existing PPCL programming, the outside air dampers for the majority of non-OAHU VAV

units were modulated to maintain the design OA flow, which was about 10%-30% of the associated max

total air flow. Since all non-OAHU VAV units don’t have return air dampers in the return air ducts and

the outside air ducts are far smaller than the return air duct size, these AHUs can’t fully use 100% OA to

implement the full economizer control. Whereas it was also found that most of the OA dampers for these

14

non-OAHU VAV units were 50%-70% open to maintain the OA flow set points, which indicated the

possibility of improving OA dampers control by partial economizer implementation.

In addition, since the OA flow sensors were critical to damper control, a total of 7 OA flow sensors were

sample checked during the retro-commissioning. It was found that 2 flow sensors were off by 20%

(field measurements were higher than Apogee readings), and 2 flow sensors had failed, which caused

the related OA dampers to fully open. Therefore, the actual OA flow almost was twice of the flow set

points. It is recommended that all of the OA flow sensors be checked and calibrated.

For AHU1-1 and AHU1-2, the outside air dampers were modulated to maintain the maximum CO2 level

in some rooms at 1,000 ppm. However, it was found that all five CO2 sensors investigated were out of

calibration (Apogee reading: 1,300-1,400 ppm; Field measured: 600-800 ppm), which drove the OA

dampers of AHU1-1 and AHU1-2 to full open, as shown in Figure 11. It is recommended that all CO2

sensors be verified and calibrated. Also, the OA damper control for AHU1-1 and AHU1-2 could be

improved by the partial economizer implementation.



Figure 11. AHU1-1 OA damper operation

6) Optimize preheat temperature setpoint if applicable

15

The pre-heat control valves were controlled to maintain the hot deck temperature at the associated

constant set points separately. The preheat temperature set points at the time of the RCP investigation

are shown in Table A - 4.

As can be seen from the table that some of the preheat temperature set points were very close or even

higher than the associated cold deck temperature set points, which could cause unnecessary

simultaneous cooling and heating. For example, as shown in Figure 12, it was found that the preheat

temperature setpoint for AHU4-3 was 53°F whereas the cold deck temperature setpoint was 50°F, which

caused both the pre-heat valve and the ChW valve to be over 10% open when the outside air temperature

was about 51°F on Nov. 16, 2008. This indicates that the preheat temperature set point could be

optimized to avoid the un-necessary simultaneous cooling and heating.



Figure 12. AHU4-3 preheat temperature control

7) Improve server room unit control

The server room on the first floor is served by a separate ChW pumping system and an individual unit

besides a fan powered box of AHU1-1. The ChW valve for the dedicated AHU in the server room was

modulated to maintain the return air temperature at 72°F. Since the sensed return air temperature reading

was 78°F on November 11, 2008, it was found that the ChW valve was fully open, and the unit

discharge air temperature and the server inlet air temperature were about 54°F and 66°F separately.

However, since the temperature distribution for the server room could be different dramatically, the

ASHRAE class 1 design standards recommend that the dedicated unit for the server rooms be controlled

16

to maintain the server inlet air temperature at 68°F to 77°F instead of using the average return air

temperature. This indicated the potential of improving the ChW valve control for the dedicated unit.

It was also observed that the sensed server space temperature was about 67°F, and in the same time, the

reheat valve of the fan power box was fully open, as shown in Figure 13, which indicated the potential

of improving the reheat valve control for the terminal box.


MMBtu/yr in HHW, for an estimated cost savings of $1,500 per year.

Figure 13. Terminal box serving the server room

Terminal Boxes

The building contains 240 terminal boxes with DDC control, the majority of which are equipped with

reheat coils. 8 terminal boxes were selected as samples to be investigated in the field during the initial

assessment process. The investigation results are summarized in Table B - 1 and Table B - 2. It was

found that one of the reheat valves was leaking by and four flow sensors and three room temperature

sensors were out of calibration. It is recommended that all flow sensors and room temperature sensors be

checked and calibrated as needed.

In addition, about 100 terminal boxes were investigated on Apogee during the RCP investigation. These

sample investigations revealed some potential opportunities to save energy as outlined below.

17

1) Optimize the min flow setting and day/night mode control for fan power boxes

At the time of RCP investigation, it was found that the flow settings for almost all the sample boxes

were kept as same as the design flow settings, and that the design minimum air flow set points for

almost all fan powered boxes serving the non-lab areas, as shown in Figure 14, were over 30% of the

related maximum air flow set points, which caused many fan power boxes to operate in heating mode.

This indicates the potential of optimizing the min flow settings for these boxes.

Figure 14. Current min/max flow settings for fan powered boxes

In addition, it was also found that the fan powered boxes serving the non-lab areas had night/day

operation mode at the time of RCP investigation, whereas many boxes were overridden at day mode.

These boxes and the related areas served by the boxes need to be addressed and the box day/night mode

control schedule could be considered if applicable.



2) Implement space temperature dead band control for lab areas

It was observed that most of the lab space temperature set points were overridden at 75°F for some

reason, and that most space temperature sensor locations were close to the door. Since the labs were

negative relative to the hallway, the cooler air from the hallway may “fool” the lab temperature sensors,

which could be one of the reasons causing the box reheat valve open. A temperature dead band control

would relieve the reheat valve partial-open issue besides achieving the energy benefit from the lower

0%

10%

20%

30%

40%

50%

60%

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Cu

rren

t B

ox

Min

/ M

ax

Flo

w S

etti

ng

s

Fan Powered Boxes

18

heating set points. It is recommended that a full survey of lab function and thermal requirement be

conducted, and that a temperature dead band control be implemented.

It is estimated that this measure would result in energy savings of 750 MMBtu/yr in HHW, for an

estimated annual cost savings of $13,000 per year.

Exhaust System

The building exhaust system is comprised of numerous exhaust fans. The major exhaust system is for

the lab tracking system. Each floor from the 3rd

to 7th

floor has between 8 and 16 lab suites, and each lab

suite is equipped with a DDC tracking system and designed to maintain a negative pressure in each lab

relative to the hallway by the offset method. Each lab suite has flow stations on the general exhaust flow,

the fume hoods exhaust flow, and the total supply flow as shown in Figure 15.

The fume hoods exhaust have maximum and minimum flow settings and the each has a flow controller

that maintains a constant face velocity until the maximum or minimum flow condition occurs. The

general exhaust air damper is controlled to maintain the general exhaust air set point, which is

determined to pressurize the lab based on the supply air flow required for temperature control, the

supply air minimum setpoint and the fume hoods exhaust. A controller on the main supply duct

regulates the supply flow to be a fixed value less than the total exhaust flow from the lab suite.

Figure 15. Lab tracking system

1) Implement OCC/UNOCC schedule and optimize the ventilation rate for lab areas

19

It was found that all lab boxes and general exhaust dampers were overridden at OCC mode, and the

ventilation rate for most of labs was about 9-12 outside air change per hour (ACH). However, the design

minimum required ventilation rate was 8 ACH during the occupied time and 4 ACH during the un-

occupied time. This indicates the possibilities of implementing OCC/UNOCC schedule and optimizing

the ventilation rate for lab areas. It is recommended that a full survey of labs schedule and ventilation

requirement be conducted, and that lowering the minimum supply and general exhaust flow setting on

occupied and unoccupied modes be considered as one option to optimize the ventilation rate for lab

areas.

In addition, based on the sample investigation results (see in Table B - 2), it was found that 6 out of 17

flow stations were off-calibrated and 1 flow station was failed, which could cause unsafe lab conditions

and waste energy. It is recommended that all of the flow stations be checked and calibrated.

It is estimated that this measure would result in energy savings of 2,530 MMBtu/yr in ChW and 760

MMBtu/yr in HHW, for an estimated annual cost savings of $50,000 per year.

Lighting System

It was observed that almost half of the exterior hallway lights near the windows were on during the

daytime at the time of investigation. It is totally not necessary for the windows day-lighting, which

indicates the potential of improved lighting control.

It is recommended that the hallway lighting control be improved by implementing time schedule. It is

estimated that this measure would result in electricity savings of 9,000 kWh/yr, for an estimated annual

cost savings of $1,000.

CONCLUSIONS

A preliminary evaluation has identified the Jack E. Brown Chemical Engineering building as a good

candidate for retro-commissioning, and a more in-depth assessment has targeted potential areas for

improvement. It is believed that the measures that have been proposed will save on energy costs, in

addition to improving comfort in the building. The major Retro-Commissioning and maintenance

opportunities are listed below:

Retro-Commissioning (RC) Opportunities:

1. Implement OCC/UN-OCC schedule and optimize the ventilation rate for lab areas

2. Implement cold deck temperature setpoint reset for all VAV AHUs and MZCAV A34

3. Implement OCC/UN-OCC schedule on the AHUs serving non-lab areas

4. Implement static pressure setpoint reset for all VAV AHUs

5. Optimize the temperature and humidity control for the SDSZ AHUs

6. Optimize the min flow setting and day/night mode control for fan power boxes

7. Implement space temperature dead band control for lab areas

8. Improve OA damper control if applicable

9. Optimize preheat temperature setpoint if applicable

10. Improve the DP setpoint reset control for the ChW and HHW pumping systems

20

Maintenance Opportunities

1. Verify and calibrate flow station, CO2 sensors, room temperature sensors, and other control points.

2. Check and adjust HHW manual valves as needed.

3. Perform necessary maintenance on the filters and valves for all AHUs and boxes.

It is expected that implementation of the RC process in this facility will yield avoided energy

consumption of 6,700 MMBtu/yr in ChW, 4,300 MMBtu/yr in HHW, and 182,600 kWh/yr in electricity,

for an estimated avoided cost of $190,000 per year, in addition to comfort improvements. The detail

savings estimated for electricity, ChW and HHW are listed in Table 5. The cost of implementing the

retro-commissioning process is roughly estimated at $80,000, which would result in a payback period of

0.4 years.

Table 5. Savings estimated for electricity, ChW and HHW

Items Unit Cost

Pre-RC Estimated Post-RC Estimated Savings

Annual Use Annual Use Annual Use Savings Energy Cost

Savings

Savings

Percentage

ELE 0.117

($/kWh)

34.7479

(kWh/ft2/yr)

33.8572 (kWh/ft2/yr) 0.8907 (kWh/ft2/yr)

0.1042

($/ft2/yr)

3%

CHW 14.775

($/MMBtu)

250.8

(kBtu/ft2/yr)

218.4 (kBtu/ft2/yr) 32.5 (kBtu/ft2/yr)

0.4800

($/ft2/yr)

13%

HHW 17.374

($/MMBtu)

63.4

(kBtu/ft2/yr)

42.8 (kBtu/ft2/yr) 20.6 (kBtu/ft2/yr)

0.3585

($/ft2/yr)

33%

21

APPENDIX A: AS-BUILT DESIGN INFORMATION

Table A - 1 CHW and HHW Pumping Information

CHW System HHW System

Number of pumps 2 2

Pump control source Apogee Apogee

Pump speed control VFD VFD

Pump speed control method DP DP

Bldg Valve control method DP DP

Control valve type DDC DDC

Nameplate GPM 3000 1070

Nameplate Head (ft) 115 110

Nameplate HP 125 50

Table A - 2 AHUs Design Information

AHU# AHU Type Area Served Total Supply Air

(CFM)

Outside Air

(CFM)

Motor

(HP)

A11 SDVAV 1st FLR 18,350 4,020 20

A12 SDVAV 1st FLR 11,120 6,745 15

A31 SDVAV 2rd FLR 9,180 1,500 10

A32 SDVAV & OAHU 2&3rd FLR 25,000 25,000 40

A33 SDVAV 2rd FLR 11,700 1,815 15

A34 MZCAV 1rd FLR Hallway 17,940 2,200 25

A35 SDVAV 3rd FLR 7,500 1,500 10

A36 SDVAV 3rd FLR 12,500 1,500 15

A41 SDVAV 4th FLR 7,500 1,700 10

A42 SDVAV & OAHU 4th FLR 21,000 21,000 30


A44 SDVAV 4th FLR 5,500 1,700 7.5

A51 SDVAV 5th FLR 7,500 1,700 10



A54 SDVAV 5th FLR 5,500 1,700 7.5

A61 SDVAV 6th FLR 7,500 1,000 10



A64 SDVAV 6th FLR 5,500 1,000 7.5

A71 SDSZ 729 6,000 - 7.5

A72 SDSZ 730 2,300 - 3

A73 SDSZ 736 2,000 - 3

A74 SDSZ 737 2,250 - 3

A75 SDSZ 731 8,000 - 7.5

A76 SDSZ 716A 2,925 - 3

22

A77 SDSZ 716B 3,500 - 5

A78 SDSZ 716C 3,700 - 5

A79 SDSZ 716D 2,200 - 3

A710 SDSZ 706 2,700 - 5

A711 SDSZ 716E 3,900 - 5

A712 SDVAV & OAHU EE O/A 12,965 12,965 20

A713 SDVAV & OAHU CHEME O/A 16,270 16,270 25

A714 SDVAV OFFICES 4,500 875 7.5

A715 SDVAV OFFICES 11,000 1,000 15

A716 SDSZ 733 21,000 - 10

A717 SDSZ 735 2,100 - 3

Total - - 393,600 218,190 533

Table A - 3 Exhaust Fans Design Information

MARK Design CFM SP INCH WC MOTOR HP

EF-1-1 3,500 1.5 2

EF-1-2 6,200 1.75 5

EF-1-3 4,920 0.7 1 1/2

EF-1-4 1,200 1.5 3/4

EF-4-1 1,330 2.25 1

EF-4-2 785 3.75 1 1/2

EF-4-3 2,100 3.75 2

EF-4-4 1,330 2.25 1

EF-4-5 1,330 2.25 1

EF-4-6 1,380 2.5 1 1/2

EF-4-7 785 3.75 1 1/2

EF-4-8 1,330 2.25 1

EF-4-9 8,500 4 10

EF-4-10 8,500 4.25 15

EF-4-11 8,500 4.25 15

EF-4-12 880 0.625 1/4

EF-4-13 9,000 3.5 15

EF-5-1 8,500 4 10

EF-5-2 8,500 4 10

EF-5-3 8,500 4 10

EF-5-4 8,500 4 10

EF-5-5 785 3.75 1 1/2

EF-6-1 8,500 3.75 10

EF-6-2 9,750 3.75 15

EF-6-3 8,500 4 10

EF-6-4 11,000 3.75 15

EF-6-5 9,800 3.5 10

23

EF-7-1 3,500 2.5 3

EF-7-2 5,900 3.75 7 1/2

EF-7-3 4,035 2.5 3

EF-7-4 440 0.35 1/8

EF-7-5 7,200 2.75 7 1/2

EF-7-6 4,400 3.25 5

EF-7-7 2,665 2.25 2

EF-7-8 750 0.75 1/4

GRH-1 2,710 0.04 -

GRH-2 2,710 0.04 -

SFP-1 5,000 1 3

SFP-2 5,000 1 3

OAI-1 6,745 0.1 -

EF-3-1 9,000 4.6 15

EF-3-2 9,000 4.6 15

Total 212,960 241

Table A - 4 AHUs temperature and pressure set point at the time of RCP

AHU#

Preheat Temp.

Setpoint

Cold Deck Temp.

Setpoint

Static Pressure

Setpoint

°F °F Inch WG

A11 52 56 3.10

A12 45 50 1.00

A31 - 56 2.75

A32 55 56 3.50

A33 - 56 2.50

A34 - 53 -

A35 - 56 1.25

A36 - 56 2.00

A41 - 56 2.50

A42 56.5 56.5 1.65

A43 53 50 2.25

A44 - 56 1.65

A51 - 56 2.00

A52 53 56 1.35

A53 53 56 2.35

A54 - 56 1.30

A61 - 56 2.00

A62 53 56 1.25

A63 55 52 1.70

A64 - 56 1.50

A714 55 55 0.75

A715 55 55 2.00

24

APPENDIX B: FIELD MEASUREMENT RECORDS

Table B - 1 Fan power boxes field measurement records

Box

#

Box

Type

RM

Served

Apogee

Reading

(CFM)

Flow

Measured

(CFM) Damper Reheat

Valve

Fan

Motor Filter

Thermostat Notes

Max. Min. Max. Min. Apogee Field

FCV

1-10

Fan

powered

constant

Study

room 113 864 268 915 265 Good Good Good x 75.3 73.5

No

return

opening

FCV

2-1

Fan

powered

constant

Library

244 770 220 725 217 Good

Valve

works;

No

water

flow

Good x 75.5 73.9

FVV

2-13

Fan

powered

Variable

Volume

Office

246 652 220 860 283 Good Good Good Clean 75 73.3

FCV

1-5

Fan

powered

constant

Classroom

106 1680 570 1870 640 Good

Leaking

by Good x 71.3 69.9

Table B - 2 Laboratories field investigation records

Room

#

Supply Flow (CFM) General Exhaust

Flow (CFM)

Fume Hood 1

Flow (CFM)

Fume Hood 2

Flow (CFM) Notes

Box# Apogee Field Apogee Field Apogee Field Apogee Field

330 LS 3-2 1020 1175 665 945 250 313 240 255

Room very negative;

Hall air coming around

space

431 LS 4-

11 1360 1540 80 255

1400

(240) 307

240

(1400) 1545

Fume hood 1&2 flow

sensor crossed on

Apogee

512 LS 5-6 1030 1095 700 915 235 308 240 302

Manual reheat valve

25% open; Supply

Temp 87.6F (reheat

valve full open)

631 LS 6-

11 1080 1130 570 615 405 308 240 520

Reheat Valve 50%

open; Supply Temp

80.6F

25

WATER LOOP INFORMATION Service: □ CHW □ HW

Supply

Return

P2

Secondary

Return Temp.Primary

Return Pressure

Secondary

Supply PressurePrimary

Supply PressureP1

Secondary

Supply Temp.

DP1 DP2 DP3

RP1 RP2 RP3

LOOP SIDE MEASUREMENTS

LOCATION TEMPERATURE PRESSURE

COMENTS Apogee Field Apogee Field

Primary Supply

43.3 72.61 72.5

Primary Return

59.5 82.0 66.5 Off calibration

Secondary Supply

42.17 43.3 80.5

Secondary Supply 1

54.98 59.4 Off calibration

Secondary Supply 2

57.41 56.9

Secondary Supply 3

52.86 52.3

Differential Pressure 1

23.33 24.4


19.12 21.1


14.98 16.30

PUMPS AND VALVE POSITIONS:

# 1 VFD Running: □ Yes Speed 30 Hz

# 2 VFD Running: □ No Speed -

Return VALVE

POSITION 100% open COMMENTS: CONDITION Good

VALVE POSITION COMMENTS:

CONDITION

FIELD FINDING: DP sensors on 6

th floor

Pressure sensor on 6th

floor, it is supply pressure

26

WATER LOOP INFORMATION Service: □ CHW □ HW

Supply

Return

P2

Secondary

Return Temp.Primary

Return Pressure

Secondary

Supply PressurePrimary

Supply PressureP1

Secondary

Supply Temp.

DP1 DP2 DP3

RP1 RP2 RP3

LOOP SIDE MEASUREMENTS

LOCATION TEMPERATURE PRESSURE

COMENTS Apogee Field Apogee Field

Primary Supply

126.5 73.75 50.0

Primary Return

103.5 9.58 39.3

Secondary Supply

128.8 126.8 59.6

Secondary Return 1

x X

Secondary Return 2

X x

Secondary Return 3

x x


19.4 20.1


20.07 20.4


20.41 19.58

PUMPS AND VALVE POSITIONS:

# 1 □ VFD Running: □ Yes Speed 27 Hz

# 2 □ VFD Running: □ No Speed

Return VALVE

POSITION 100% open COMMENTS: CONDITION Good

VALVE POSITION COMMENTS:

CONDITION

FIELD FINDING: DP sensors on 6

th floor

27

AHU Information AHU: 1-1 Type: Single-Zone

Area Served: Computer rooms and offices

H

C

1 5 6 74

2 RA

OA

C

C

3

AIR-SIDE MEASUREMENTS

POSITION FLOW (CFM) TEMP (°F) S.P. (in WG) Notes

# Descrip Apog. Field Apog. Field Apog. Field

1 OA 3150 3370 66.1 -0.44

OA damper 100% open

VFD 83%

2 RA 9700 71.3 -0.45

3 Mixed Air 69.7 -0.40

4 After Filter -0.74

5 Preheat 69.8 69.8 -0.81

6

After

CHW 55.9 56.1 -1.16

7 Discharge 58.1 3.1 2.02

WATER-SIDE MEASUREMENTS

LOCATION

VALVE PRESSURE(100% VAVLE OPEN)

NO/NC Range Position Leaking By? Before Strainer After

Strainer Before Valve After Valve

HHW - 100% No 62 53.8 51

CHW - 100% 69.3 64.4 63.1

DAMPER OPERATION

LOCATION

DAMPER

NO/NC Range Current

Position

Min

Position

OA N/C DDC 100%

RA No

Damper

28

AHU Information AHU: 1-2 Type: Single-Zone

Area Served: Classrooms

H

C

1 5 6 74

2 RA

OA

C

C

3




1 OA 2062 2460 62.1 -0.086

CHW 32% VFD = 60% - 65%

2 RA 71.1 -0.08

3 Mixed Air -0.086

4 After Filter 68.4 -0.12

5 Preheat 65.8 68.7 -0.125

6 After CHW 48.9 48.2 -0.27

7 Discharge 5600 49.6 1.0 1.05

VFD


LOCATION


NO/NC Range Position Leaking

By? Before

Strainer After

Strainer Before Valve

After Valve

HHW N/O DDC 100% open No 58.5 59.7 57.5 49.3

CHW N/O DDC 100% open no 65.0 66.3 63.2 61.2

DAMPER OPERATION

LOCATION DAMPER

NO/NC Range Current Position Min Position

OA N/C DDC 100% open

RA No Damper

FIELD FINDING:

29

AHU Information AHU: 3-4 Type: Multi-zone Bypass

Area Served: Hallway

C

CC

C

C

H

C

H

1

2 3

4

5 6

7 8

RA

OA

Zone 1

Zone 2




1 Mixed Air 70.1 -0.43


3 After Fan 70.7 1.13

4 After CHW 52.5 53.1 2.8

5 Z2 Before HW 57.1 1.59

6 Z2 Discharge 59.5 56.5 0.234

7 Z1 Before HW 54.3 0.38

8 Z1 Discharge 54.3 54.2 0.40

VFD


LOCATION



By? Before Strainer

After Strainer

Before Valve

After Valve

HHW

CHW

DAMPER OPERATION

LOCATION

DAMPER

NO/NC Range Current Position

Min Position

OA

RA

FIELD FINDING:

30

AHU Information AHU: 4-3 Type: Single-Zone OAHU

Area Served: Labs

C

C

1 4 53

OA

2

C

H




1 -0.033

OA filter dirty

2 71.0 -0.043

3 71.7 71.3 -0.172

4 52.2 52.5 -0.520

5 52.8 2.24 2.17

VFD


LOCATION



By? Before Strainer

After Strainer

Before Valve

After Valve

PHW N/C 43.2 34.2 33

CHW 50.5 47.9 46.9

HHW

DAMPER OPERATION

LOCATION

DAMPER


Min Position

OA 100%

RA

FIELD FINDING:

31

AHU Information AHU: 4-4 Type: Single-Zone AHU

Area Served: Labs

1 5 6 74

2 RA

OA

C

C

3




1 OA 3980 54.3 -0.109

2 RA 54.5 -0.006

3 Mixed Air -0.050


5

6 After CHW 53.3 54.9 -0.274

7 Discharge 3530 55.8 1.65 1.675

VFD 60.3% 36.1 Hz


LOCATION



By? Before Strainer

After Strainer

Before Valve

After Valve

CHW 52 48.8 46.9

DAMPER OPERATION

LOCATION

DAMPER


Min Position

OA

RA

FIELD FINDING:

32

AHU Information AHU: 6-2 Type: Single-Zone OAHU

Area Served: Labs

C

C

1 4 53

OA

2

C

H




1 OA 76.8 -0.05

VFD 43 Hz Apogee – 48.9% OA filter dirty

2 After Filter -0.33

3 Preheat 75.3 75.6 -0.41

4 After CHW 55.9 57.8 -1.0

5 Discharge 59.3 1.23 1.27

VFD


LOCATION



By? Before Strainer

After Strainer

Before Valve

After Valve

PHW 35.2 31.5 29.3

CHW N/C 25 22.5 22.5

DAMPER OPERATION

LOCATION DAMPER

NO/NC Range Current Position Min Position

OA 100% open

RA

FIELD FINDING:

Documents

Continuous Commissioning® Assessment Report · 2011-11-21 · Experiment Station (TEES) under contract to Sandia National Laboratory ... Of the boxes, 112 are parallel fan powered