Economizer Procedure.rtf

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CxTPL Upgrade Project Oct. 31, 2001

GENERAL COMMISSIONING PROCEDURE FOR ECONOMIZERS

Prepared for:

Pacific Gas & Electric Company,Customer Energy Management Non-Residential New Construction Program

Development of a Commissioning Test Protocol Library Project

Alyssa Newman, Project Manager Ken Gillespie, Project Lead

Prepared by:

Pacific Gas & Electric Company,

Technical and Ecological Services, Performance Test and Analysis UnitRichard Fromberg

The project “Development of a Commissioning Test Protocol Library” is funded by California

utility customers and administered by Pacific Gas & Electric Company under the auspices of theCalifornia Utilities Commission.

Legal Notice

Pacific Gas and Electric Company (PG&E) makes no warranty or representation, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in

this report, or that the use of any information, apparatus, method, or process disclosed in thisreport may not infringe upon privately owned rights. Nor does PG&E assume any liability with

respect to use of, or damages resulting from the use of, any information, apparatus, method, or process disclosed in this procedure.



CxTPL Upgrade Project Oct. 31, 2001

CONTENTS

General Commissioning Procedure for Economizers

FOREWORD ……………………………………………………………………….1I. PROJECT / BUILDING DESCRIPTION………………………………………...2

II. SEQUENCES OF OPERATION………………………………………………...4

III. ACCEPTANCE AND RESPONSIBILITIES..………………………………….5

IV. VERIFICATION – CHECKS FOR REQUIRED DOCUMENTATION ANDTRAINING………………………………………………………………….6

V. VERIFICATION – NAMEPLATE DATA CHECKS…………………………..7

VI. VERIFICATION – INSTALLATION CHECKLIST………………………….10VII. VERIFICATION – CONTROLS SENSOR CALIBRATION CHECKS..…...13

VIII. VERIFICATION – BALANCE REPORT CHECKS………………………. 14IX. VERIFICATION – OPERATIONAL CHECKS

1) EXERCISE DAMPERS…………………………………………………15

2) FIRE ALARM ECONOMIZER DAMPER POSITIONS.………………17

3) ECONOMIZER MODE CHECKS………………………….…………...184) CONTROLS PROGRAM CHECKS…………………………………….20

X. FUNCTIONAL CHECKS – FORCED RESPONSE AND SEQUENCE OF

OPERATION TESTING – FANS ON/OFF, MORNING COOL-DOWN OR

WARM-UP, NORMAL OPERATING MODES, FIRE/SMOKE ALARM,FREEZE PROTECTION AS-BUILT RECORDS …………..…………………21

XI. FUNCTIONAL TESTS – ECONOMIZER PERFORMANCE TEST..………..25

XII. FUNCTIONAL TESTS – ECONOMIZER OPERATIONAL TREND TEST..26XIII. FUNCTIONAL TESTS – M&V SAVINGS CALCULATION USING

PERFORMANCE TRENDING TESTS ……………………….……………….27

XIV. COMMISSIONING REPORT OUTLINE……………………………………29XV. REFERENCES USED TO DEVELOP THE ECONOMIZER PROTOCOL…30



General Commissioning Procedure for Economizers October 31, 2001

FOREWORD

This procedure provides example protocols for two fictitious buildings (one located in

Sacramento and the other in San Francisco) for steps that need to be taken to fully commission

their air handling system’s economizers. Variations are provided when requirements between thetwo examples differ. Each building has integrated, built-up economizers, with return, exhaust

and outside air dampers, but different sequences of operation and designs.

In commissioning an economizer, the intent is to optimize the use of outside air for cooling a

building, in order to minimize energy use, while maintaining good indoor air quality. Our

primary goal is to verify that the economizer is working as specified, while looking for opportunities to improve upon its intended operation. This procedure was developed with the

assistance of PG&E’s Commissioning Test Protocol Library’s Templates. Following is an

outline of what protocols are included here:

Project/Building DescriptionDescription of Systems Under Test

Equipment Covered by this ProtocolSequences of Operation

Acceptance and Responsibilities

Verification ChecksChecks for Documentation and Training

Nameplate Data Checks

Installation ChecklistControls Sensor Calibration Checks

Balance Report Checks

Operational Checks -1) Exercise dampers2) Fire Alarm Economizer Damper Positions

3) Economizer Mode Checks

4) Controls Program ChecksFunctional Tests

Forced Response and Sequence of Operation Testing – Fans On/Off, Morning Cool-down or

Warm-up, Normal Operating Modes, Fire/Smoke Alarm, Freeze ProtectionEconomizer Performance Test

Economizer Operational Trend Test

M&V Savings Calculation using Performance Trending Tests – Outline of Procedure

References Used to Develop the Economizer ProtocolResults and Recommendations Report

Richard Fromberg 3 184002250

Pacific Gas and [email protected]




I. PROJECT / BUILDING DESCRIPTION

BUILDING NAME and ADDRESS: APPLICATION #: 1

Case 1) Sac’s Service Center (SSC)

4444 Perk Road, Sacramento CA 95826 and

Case 2) Pete’s Excellent Cuisine (PEC)

185 Energy Street, San Francisco, CA 94102

BUILDING CONTACT PERSONS and PHONE NUMBERS: 1) Zachery Sac, 916-123-4567 2) Peter Cook, 415-123-4567

NAME & FIRM OF PERSON(S) DOING TESTS: JR Doolittle, Hotwire Commissioning Services

PLANNED DATE(S) OF TEST: December 21-23, 2001

Description of Systems Under Test:1) The SSC has three air handler units (AHU’s) #1, #2 and #3, which serve the north, south, and southeast sections of the

main building. Supply and return fans are VFD controlled. A DDC system controls separate actuators on the outside

air, return air and exhaust air dampers. AHU#1 and AHU#2 are roof mounted; AHU#3 is floor mounted at the east

end of the building.

The air handlers are designed to provide hot and cold duct air flows that will maintain 0.25 “wg supply air duct static

pressures and a supply air temperature set point of 55°F. Minimum supply air rate is limited to 25% of the total

capacity. The sequence of operation for each AHU is the same, except for scheduling differences. The environment is

a hot/dry central valley climate with seasonal temperatures ranging from 15°F -105°F and the cooling load is ~75 tons

@ 40,000 cfm per AHU.

2) The PEC has one air handler unit, AHU-1, which serves a multi-zone, single duct, reheat system that conditions the

whole building. AHU-1 is a central station, pull-thru type, roof mounted air handling unit complete with economizer

(return, outside, exhaust) damper section, filter section, chilled water cooling coil section and fan section with variable frequency drive (VFD) control of the supply fan motor. Exhaust fans are propeller type fans within the air handler exhaust section.

The air handler is designed to provide conditioned air at the temperature and pressure required by the variable volume

(VAV) terminal units and outside air as required for (IAQ) ventilation. It also provides exhaust air as required to

maintain a slight building positive pressure during economizer operation. The environment is a coastal climate withtypically mild temperatures ranging from 35°F to 95°F and the cooling load is ~60 tons max @ 32,000 cfm.

The air handler is designed to provide air flow that will maintain between 1” and 2”wg supply air duct static pressure

and supply air temperature set point between 65 and 55°F.






Equipment Covered by this Protocol: Economizers of AHU’s 1, 2, and 3 at the SSC and AHU-1 at the PEC.

General Notes:

1. This commissioning procedure addresses verification checks and functional testing of moderately sized packaged or

built-up air handlers.

2. In all test sections, circle or highlight any results that indicate deficiencies (i.e. responses that don’t meet the criteria for acceptance). Acceptance requires correction and retest of all deficiencies, as defined in each test section under

“Criteria for Acceptance” or “Acceptance”. Attach all retest data sheets.

3. This Commissioning Procedure does not comprehensively address fire and life safety or basic equipment safety

controls.

4. To ensure that this Commissioning Procedure will not damage any equipment or affect any equipment warranties, have

the equipment manufacturers’ representative(s) review all test procedures prior to execution, and be present if possible.






II. SEQUENCES OF OPERATION

Case #1 - The economizer air dampers (outside, return and exhaust) shall be modulated by an analog output from the DDC

system to maintain the desired cold deck temperature set point. A minimum of 45F mixed air temperature will be maintained at

all times.

Cooling supply air temperature shall be maintained by first modulating the outdoor air damper open via the economizer mode

and then secondly modulating the chilled water valve open. When the outdoor air temperature is within 2F (adjustable) below

the warmest zone space temperature, the outside air damper shall go to the minimum position setting and the return damper

shall open to maximum position. The heating supply air temperature shall be reset downwards to the return air temperature as

required to maintain a zone temperature of 70F(adjustable) in the coldest room.

A photoelectric duct smoke detector shall be installed in the supply duct and shall provide a digital input to the DDC system.

When smoke is detected by the smoke detector, the air handler supply fan shall be de-energized via its variable frequency drive,

the return fan shall be de-energized via its VFD, and the outside air damper shall be fully closed.

All damper actuators shall be programmed to achieve full range adjustability (closed to 100% open) in 60 seconds (adjustable).

Case #2 – AHU-1 is programmed to operate (on/off) on a predetermined building occupancy schedule (adjustable).

When the supply fan is de-energized, the outside damper shall close and the cooling coil chilled water control valve TCV-1 shall

open to the full bypass position.

The supply fan is energized one hour (adjustable) prior to scheduled occupancy to provide a warm-up cycle. The outside air

damper shall remain closed and the cooling coil chilled water control valve shall remain open to the full bypass position during the warm-up. The warm-up cycle shall be terminated when return air temperature TS-4 reaches 70°F.

The supply air temperature TS-3 shall be controlled by modulating the economizer dampers and then the cooling coil chilled water control valve TCV-1 in sequence to maintain the supply air temperature at set point. Outside air via the economizer

dampers shall be the primary source of cooling when outside air temperature TS-1 is below 72°F and less than the return air temperatureTS-4, otherwise cooling shall be provided by chilled water via TCV-1. No chilled water shall be supplied to

TCV-1 when outside air temperature TS-1 is below 61°F. Supply Air Temperature TS-3 setpoint shall be reset by greatest

cooling demand from 55F to 65F. When outside air temperature TS-1 is greater than 72°F or greater than the return air

temperature TS-4 the economizer dampers shall be positioned to provide the minimum design outside air CFM.

Building static pressure DPX-1 shall be maintain at 0.03”wg for economizer operating mode only. No set point control is

required for minimum outside air operating mode. Supply Air Duct Static Pressure DPX-2 setpoint shall be reset via AHU-1 supply fan VFD by greatest cooling demand from 1.0” wg to 2.0” wg.

ALARM SETPOINTS:

Building Static Pressure DPX-1: 0.07 “ wg.Supply Air Duct Static Pressure, High: 2.4 “wg, Low: 0.06 “wg

Supply Air Temperature TS-3, Low: 50°F

Return Air Temperature TS-4, High: 76°F, Low: 60°F

Mixed Air Temperature TS-2, Low: 50°F Filter (Dirty) Differential Pressure DPS-2: 1.0 wg.






III. ACCEPTANCE AND RESPONSIBILITIES:

We the undersigned participated in this commissioning effort, and acknowledge that the processes for which we were

responsible have been checked and all required corrections have been made.

1. Name: Joe Contractor

Company name: Installation Contractor Associates

Responsibilities:

Verification Checks: Installation quality, dampers must match position commanded by DDC

Functional Testing: Dampers must respond to DDC commands in time, reliably, and accurately.

Signature:

2. Name: John Programmer

Company name: DDC Inc.

Responsibilities:

Verification Checks: DDC must be capable of commanding dampers to the required positions based on operating

mode. Pre-operational forced response testing must be verified.

Functional Testing: DDC must be capable of commanding dampers to the required positions based on operatingmode, OAT conditions, and as specified in the sequence of operation

Signature:

3. Name: JR Doolittle

Company name: Hotwire Commissioning Services

Responsibilities:

Verification Checks: Complete the commissioning plan, ensure that all corrections are made, retest if necessary,

use best engineering judgement to achieve design intent.

Functional Testing: Complete the commissioning plan, ensure that all corrections are made, retest if necessary, use

best engineering judgement to achieve design intent.

Signature:

4. Name: Zachary Sac

Company name: Sac’s Service Center

Responsibilities: The building owner’s representatives are to facilitate the commissioning process, to help ensure that

corrections are made, and to work with all parties to achieve an optimum product.

Verification Checks:

Functional Testing:






Signature:






IV. VERIFICATION - CHECKS FOR REQUIRED DOCUMENTATION AND TRAINING:

Requested documentation to be submitted. (This section to be completed by Commissioning Authority (CA).)

Documentation Equipment Dampers Actuators Control

Wiring

Programming

Equipment manufacturer’s submittals, shop drawings, as-builts Manufacturer’s performance sheets (i.e. flow coefficient versusdamper position)

Installation manual

Test and Balance report

Sequences of Operation

O&M manuals

Warranties

Documentation complete as per contract documents ___ YES ___ NO

Required training. (This section to be completed by CA.)

Documentation Equipment Dampers Actuators Control

Wiring

Programming

Controls and equipment training

EMS training

Documentation complete as per contract documents ___ YES ___ NO






V. VERIFICATION - NAMEPLATE DATA CHECKS:

Instructions: Enter information available from design specifications, submittals and installed equipment nameplates.

Criteria for Acceptance: Nameplate data must be in accordance with submittals as approved by Designer.

DESCRIPTION Outside Air Damper

As specified As submitted As installed

Manufacturer

Model #

Serial #

Type

Maximum CFM

Minimum CFM

Damper Size (_____ x _____)

Maximum Velocity (fpm)

Maximum Pressure Differential (in. Wg.)

Comments on Nameplate Data Checks (add more sheets if needed):

# COMMENT

DESCRIPTION Exhaust Air Damper


Manufacturer

Model #

Serial #

Type

Maximum CFM

Minimum CFM








# COMMENT

DESCRIPTION Return Air Damper


Manufacturer

Model #

Serial #

Type

Maximum CFM

Minimum CFM





# COMMENT

DESCRIPTION Outside Air Damper Actuator


Manufacturer

Model #

Serial #

Type

Electrical Data (i.e. signal range)

Maximum Position

Minimum Position







# COMMENT

DESCRIPTION Exhaust Air Damper Actuator


Manufacturer

Model #

Serial #

Type


Maximum Position

Minimum Position


# COMMENT

DESCRIPTION Return Air Damper Actuator


Manufacturer

Model #

Serial #

Type


Maximum Position

Minimum Position


# COMMENT






VI. VERIFICATION - INSTALLATION CHECKLIST:

Instructions: Under each unit write "Y" for yes, "N" for no, "NA" for not applicable, and a number to refer to any needed comments. Identify responsible contractor. If issues or concerns arise, number and note in comment section below.

Criteria for Acceptance: Answers of “Y” (or “NA”, where not relevant) except where other criteria are noted.

Caution: Only qualified personnel familiar with the operation of the installed economizers, and the hazards involved, should adjust, operate, test, and/or service the equipment. The commissioning agent should become familiar with the installation,

operation, and maintenance manuals prior to starting commissioning work. Failure to observe proper safety precautions could

result in damage to equipment, severe bodily injury, and/or loss of life.

Check SSC AHU

1

SSC AHU2

SSC AHU3

PEC AHU1

Comments

General Installation

General appearance good, no apparent damage

Environment clean

Good access for maintenance Access doors close tightly – no leaks

Equipment labels affixed properly

Economizer installed in accordance with manufacturer’s specsand drawings

The installation and location of the economizer are in a neutral

zone of the building (i.e. there are no undo pressure restrictions

or drops that hinder air movement)

Outside air intake is located away from pollutant sources and

exhaust outlets

Damper Installation

Dampers and linkages installed in accordance with drawings

Dampers are properly linked, and move in the right directions Linkages have minimum play

Installed dampers match specifications

Dampers move freely without binding and are fully operational.There are no unusual noises when operating.

Actuators are mounted to maximize torque available to the

damper and to maximize linearity between the blade position and the actuator stroke.

Multiple section dampers with multiple actuators need to haveidentical actuators and linkages to make each section’scharacteristics consistent.

Blade lengths of 48 inches or less are desirable, to reduce flutter

and improve sealing.

Dampers close tightly

Dampers are lubricated. Vertical blades have thrust bearings.

Outside air and return air dampers mounted to promote thoroughmixing of the two airstreams prior to entering coils

Dampers are pointing in the direction that facilitates efficient

air movement






Verify that damper actuators are marked as follows: 0%

position where the damper is closed, XX% position for the

damper minimum air flow position, and 100% position where

the damper is fully open.

Ductwork

Ductwork installed in accordance with design drawings

All duct and boot connections to economizer are complete and in good condition

Fittings in ductwork properly specified and appropriate for theapplication

Ductwork complete and leak tested

Mixing

Is there enough space between the mixing section and the coils for adequate mixing?

Are baffles installed and are damper blades rotating in thedirections that facilitate mixing?

Sensors

Outside air temperature sensor installed in correct location, out

of direct sunlight and away from economizer inlet or outlet.Outside air sensor matches specification

Return air sensor installed in correct location

Return air sensor matches specification

Mixed air sensor installed in correct location, to ensure proper mixing of airstream ahead of sensor, and/or enough sampling

points.

Mixed air sensor matches specification

Calibrations are covered in the next section

Low limit freeze stat installed in correct location, not affected

by stratification and bypass

Low limit freeze stat matches specification

Smoke detectors installed in correct location(s)

Smoke detectors match specifications

Filter differential pressure device installed in correct location,

functional

Filter diff pressure sensor matches specification

Air Filters

Construction filters removed

Air filters are installed and clean and new

Air filters match specifications

Air filters are tight fitting

Replacement filter type and efficiency permanently affixed to

AHU housing Electrical

Electrical connections are tight

Duct penetrations are waterproof

Power disconnects, connection boxes and conduit are watertight

Panels and boxes are properly labeled

Fuse rating is correct for electrical equipment

Power is available to panels






Shielded wiring used on electronic controls

Ductwork and penetrations

Verify that wall and floor penetrations are properly sealed

Verify that pressure relief doors are installed

Verify that duct insulation is installed

Verify that sound attenuation sections are installed

The checklist items are all successfully completed for given trade. ___ YES ___ NO

Comments on Installed Characteristics Checks (add more sheets if needed):

# COMMENT






VII. VERIFICATION - CONTROLS SENSOR CALIBRATION CHECKS:

Instructions: For each sensor listed below, collect the following information:

1. Instrument description/identification

2. Manufacturer’s calibration requirements

3. Copy of the most recent calibration certificates

4. Date of most recent calibration and the calibration data

5. Description of the calibration procedure

Installation: Check that all sensor installations and locations are correct, in order to attain an accurate measurement of the

process. Make sure that they are installed out of direct sunlight, and in the ductwork where the process is mixed and uniform.

Sensor elements should not touch any surfaces. The outdoor air sensor should be located away from the economizer inlet or

exhaust, so that it is not affected by natural drafts when the AHU is off. If sensor location is improper, explain in comments, and have it relocated. Verify that sensors with shielded cable, are grounded only at one end. It is not necessary to repeat any full

calibration procedure, but we recommend that through-system calibration checks be made, as follows:

Differential paired sensors. For sensor pairs that are used to determine a temperature or pressure difference, place both sensors

into a uniform temperature bath or expose them to the same pressure. Make sure that they are reading within 0.2°F of eachother for temperature and within a tolerance equal to 2% (of the reading) of each other for pressure. Tolerances for critical

applications may be tighter.

Sensors. Take a reading of the process with a calibrated test instrument close to the site sensor. Verify that the readings are

within the tolerances in the table below. If not, install an offset in the BAS, recalibrate, or replace the sensor. If a second

instrument cannot be installed to take a second reading, remove the sensor and subject it to a temperature bath or pressure

source along with a calibrated sensor, and compare the readings. Record the readings in the table below.Criteria for Acceptance: Temperature and pressure sensors should agree with the calibrated instrument within the tolerances

listed below.

CONTROLTYPE

CAL

SENSOR LOCATION

EMS

SENSOR LOCATION.

IS IT

OKAY?

EMS

MEASUREDVALUE

CALIBRATION

SENSOR VALUE

DIFFERENCE ACCEPTABLE

DIFFERENCE

ACCEPTABLE? /

COMMENTS

Outdoor air temp

SF(.5F),Sac(1F)

Mixed air

temp

1F

Return air

temp

SF(.5F),Sac(2F)

Filter

Differential

Pressure

0.2 inH2O

Comments on Calibration Items (add more sheets if needed):

# COMMENT






VIII. VERIFICATION - BALANCE REPORT CHECKS:

Instructions: Compare the maximum supply air flow (outside air damper open) documented in the TAB report with the design flow specifications for the economizer dampers. From the TAB report, record the minimum outside air flow when the outside air

damper is at its minimum position with both the supply fan operating at full and at minimum. Compare TAB report flows with

economizer specifications and with the HVAC system design specifications.

Criteria for Acceptance: Test and balance report outside air flows must meet the following criteria: the measured flow must

be greater than the specified flow, and less than 110% of the specified flow. Also, the measured flows must be less than the

damper design maximum flows.

Check Measured Flow

(from TAB)

Specificationand Damper

Design Flows

% Diff Acceptable?

Maximum outside air flow with outside air damper full

open, 100% supply air flow

Minimum outside air flow with outside air damper at minimum and supply fan at 100%

Minimum outside air flow with outside air damper at

minimum and supply fan at minimum RPM

Test and balance report is verified to be in agreement with economizer design specifications? ___ YES ___ NO

Test and balance report is verified to be in agreement with system minimum outside air design specifications?

___ YES ___ NO






IX. VERIFICATION - OPERATIONAL CHECKS – 1) EXERCISE DAMPERS:

Instructions: These verification checks augment the manufacturer’s instructions. These checks are done prior to functional testing, which are performed while the system is operating normally. Fill in the appropriate values if other information is

requested, such as damper position (%) or temperature. Identify responsible contractor.

Damper Stroke Check This test is to verify that the dampers can operate throughout their full expected range, and that the damper position matches the

position called for in the BAS. Follow the steps in the table below for each damper and economizer.


Caution: Only qualified personnel familiar with the operation of the installed air handler, and the hazards involved, should

adjust, operate, test, and/or service the equipment. The commissioning agent should become familiar with the installation,



Enter “Y”, “N”, “NA”, or data as requested. Enter comment or note number if deficient.

Check Equipment-> SSC AHU 1

SSC AHU2

SSC AHU3

PEC AHU1

Contractor

Value/ Comments

Air handler fans are off.

Command outside air damper to 100% open.

Is outside air damper fully open?

Is outside air damper position indicator pointing to 100%.

Make sure that the scale is labeled to indicate the 100% position.

Is exhaust air damper fully open?

Is exhaust air damper position indicator pointing to 100%.


Is return air damper fully closed? Is return air damper position indicator pointing to 0%.


Command outside air damper to 0% open.

Is outside air damper fully closed?



Is exhaust air damper fully closed?



Is return air damper fully open?

Is return air damper position indicator pointing to 100%. Make sure that the scale is labeled to indicate the 100% position.

Command outside air damper to its minimum operating position.

Is outside air damper at 20% (as specified)?



Is exhaust air damper at 20% open?








Is return air damper at 80%?

Is return air damper position indicator pointing to 80%.


Determine damper opening speed.

Command the outside air damper to 0%Command the outside air damper to 100% open and record the time it takes to fully open. Note any unusual noises or problems.

Record the time it takes for the exhaust damper to open and note any

unusual noises or problems.

Record the time it takes for the return damper to close and note anyunusual noises or problems.

Determine damper closing speed.

Command the outside air damper to 0% open and record the time it takesto fully close. Note any unusual noises or problems.

Record the time it takes for the exhaust damper to close and note anyunusual noises or problems.

Record the time it takes for the return damper to open and note any

unusual noises or problems.

Return outside air damper to its normal position.


Comments on Operational Checks (add more sheets if needed):

# COMMENT






IX. VERIFICATION - OPERATIONAL CHECKS – 2) FIRE ALARM ECONOMIZER DAMPER

POSITIONS:

Instructions: These verification checks augment the manufacturer’s instructions. These checks are done prior to functional

testing, which are performed while the system is operating normally. Fill in the appropriate values if other information is


Check Damper Response to a Fire/Smoke Alarm

This test is to verify that the dampers respond properly to a fire or smoke alarm. Follow the steps in the table below for eacheconomizer.




operation, and maintenance manuals prior to starting commissioning work. Failure to observe proper safety precautions could result in damage to equipment, severe bodily injury, and/or loss of life.

Enter “Y”, “N”, “NA”, or data as requested. Enter comment or note number if deficient.Check Equipment-> SSC

AHU 1

SSC

AHU2

SSC

AHU3

PEC

AHU1

Contrac

tor

Value/

Comments

Verify that the air handler fans are off.

Command the outside air damper to 100% open. The exhaust damper

should be full open and the return damper should be closed.

Set the fire/smoke detection system input signal to ON.

Does the outside air damper close completely?

Does the return air damper close completely?

Does the exhaust air damper close completely?

Reset the fire/smoke detector input signal to OFF.

Do all dampers return to their normal position?



# COMMENT






IX. VERIFICATION - OPERATIONAL CHECKS – 3) ECONOMIZER MODE CHECKS

Instructions: These verification checks augment the manufacturer’s instructions. These checks are done prior to functional testing, which are performed while the system is operating normally. Fill in the appropriate values if other information is


Check Economizer Damper Responses in Different Operating ModesThis test is to verify that the dampers respond properly to various input conditions in different operating modes. Follow the

steps in the table below for each economizer.


Caution: Only qualified personnel familiar with the operation of the installed air handler, and the hazards involved, should adjust, operate, test, and/or service the equipment. The commissioning agent should become familiar with the installation,





SSC AHU2

SSC AHU3

PEC AHU1

Contractor

Value/ Comments

Disconnect power to supply and exhaust fans to make sure that they do not turn on throughout the following tests.

Set BAS to Unoccupied (Fan Off) Mode

Verify that outside air damper is closed.

Verify that return air damper is open.

Verify that exhaust air damper is closed.

Set BAS to warm-up mode.

Outside and exhaust air dampers closed?

Return air damper open?

Set BAS to cool-down mode.

Set outside air temp to 65F

Outside and exhaust air dampers are full open?

Return air damper is closed?

Set outside air temp to 75F.

Outside damper is at minimum and exhaust damper is closed?

Return air damper is full open?

Set BAS to Occupied Mode

(For the SSC) Set outside air temp to 3F less than the warmest zonetemperature.

(For the PEC) Set the outside air temp to 71F or 1F less than the return

air temp, whichever is less.

Verify that outside air damper is full open.

Verify that return air damper is closed.

Verify that exhaust air damper is full open.

(For the SSC) Set outside air temp to 1.5F less than the warmest zonetemp

(For the PEC) Set the outside air temperature to 73F.

Verify that outside air damper is at minimum.






Verify that return air damper is full open.


(For the SSC) Check that the minimum mixed air temperature is

maintained. Set the mixed air temp to 2F less than the minimum set

point for mixed air temp of 45F.

(For the PEC) Check that the supply air temp set point can be controlled.

Set the supply air temp to supply air temp set point minus 2F.

Set the outside air temperature to 40F and the return air temperature to

70F.




(For the SSC) Set the mixed air temp to 47F.

(For the PEC) Set the supply air temp to supply air temp set point plus2F.

Verify that outside air damper is full open.

Verify that return air damper is closed.

Verify that exhaust air damper is full open.

Release the mixed, supply, and outdoor air temperature overrides and the

BAS to its normal state.



# COMMENT






IX. VERIFICATION - OPERATIONAL CHECKS – 4) CONTROLS PROGRAM CHECKS


Check Equipment-> SSC AHU

1

SSC AHU2

SSC AHU3

PEC AHU1

Contractor

Value/

Comments

Have flow charts and/or other documentation of the software specific tothe SSC and PEC been provided?

Check the logic diagrams for the economizers. Do they accurately model

the sequences of operation, as follows:

Shut down?

Warm-up?

Cool-down?

Occupied Mode?

Economizer Mode (free cooling)? Is the logic set up to modulate theeconomizer to maintain supply air temp (PEC) or a minimum mixed air

temp (SSC)?

Minimum Outside Air Mode?

Fire/Smoke Alarm Mode?

Freeze Protection?

Check the building occupancy schedules. Is the PEC M to F 7:00A to6:00P and is the SSC M to F 6:30A to 5:30P, with AHU#3 24-7?

Is the warm-up or cool-down mode scheduled to begin 1 hour beforeoccupancy?

Are there alarms set for economizer malfunctions?

Have graphics screens of the economizer and associated temperatures

and damper positions been set up?

Are the graphics screens easy to access from other graphics screens?

Are trends set up to store economizer data?Can 48 hours of data be retrieved and plotted conveniently from the BAS

for each economizer?

Is the % outside air to total air calculated?


Comments on DDC Program Checks (add more sheets if needed):

# COMMENT






X. FUNCTIONAL CHECKS – FORCED RESPONSE AND SEQUENCE OF OPERATION

TESTING - FANS ON/OFF, MORNING COOL-DOWN OR WARM-UP, NORMAL OPERATING

MODES, FIRE/SMOKE ALARM, FREEZE PROTECTION

The functional tests that follow include forced response tests and sequence of operation tests. Protocols for operational

trend tests follow.General Instructions: The following sections are a series of field tests that are intended to verify that the economizer, as

installed, operates as it was intended to operate by the designer. In general, these tests are best done with the building

unoccupied or lightly occupied. Environmental conditions will be affected. If that is not possible, the commissioning agent must devise tests that are not intrusive. Some tests may involve trending normal operation over a long enough period to observe the

conditions and modes of operation desired.

Attach to this form all relevant field data, monitored data, graphs, trend logs, and so forth. Annotate any data and graphs so that

it is clear what the data are proving. EMS trend logs of EMS outputs, program print-outs, or schedule and setpoint print-outsare not acceptable as proof of operation, unless the information is first verified to be accurate and documentation is attached.

Trend logs of sensor inputs to the EMS are acceptable. If you were not able to complete a test, explain in a comment.

Instructions: These functional checks augment the manufacturer’s instructions, and are to be performed when the system is

operational. Fill in the appropriate values if other information is requested, such as damper position (%) or temperature. Identify responsible contractor.

Check Economizer Damper Responses when the Fans are Turned On and Off, then during Morning Cool-down and Warm-

up, then during Normal Occupied Operating Modes

These tests are to verify that the dampers respond properly to various input conditions in different operating modes. Follow the steps in the table below for each economizer.







Check Equipment-> SSC

AHU 1

SSC

AHU2

SSC

AHU3

PEC

AHU1

Contrac

tor

Value/

Comments

Make sure that the AHU is ready for functional testing.

Verify stable operation of the AHU and fans before commissioning.

Set BAS to Unoccupied (Fan Off) Mode

Are the supply and exhaust fans off?




Set BAS to Occupied mode to turn the fans back on.

Verify that the outside and exhaust air dampers (or the return air dampers) are open before the fans start.

Do the fans start after the dampers are open?

Record fan speed.






Set fan speed to 100%.

Record the filter differential pressure at 100% supply air flow.

Is the differential pressure close to what was specified in the AHU design.

Set BAS to cool-down mode.

Record the return air temperature.

Set outside air temp to 2F below the RAT.

Outside and exhaust air dampers are full open?

Return air damper is closed?

Record the return air temperature again.

Set outside air temp to 2F above the RAT.


Return air damper is full open?

Set BAS to warm-up mode.

Record the return air temperature.Set outside air temp to 2F below the RAT.


Return air damper is open?

Record the return air temperature again.

Set outside air temp to 2F above the RAT.

Outside damper and exhaust damper are open?

Return air damper is full closed?

Test the Economizer’s normal operating modes

Set BAS to Occupied Mode

Are the fans running?For the PEC:

Set the supply air temperature set point to 55F.

Set the return air temperature to 73F.

Set the outside air temperature to 74F.

Is the outside air damper at minimum, the return air damper full open,

and the exhaust air damper closed?


Is the outside air damper at minimum, the return air damper full open,and the exhaust air damper closed?


Are the outside and exhaust air dampers full open and return air

damper closed?

Set the supply air temperature reading to 50F (below the SA set point).

Do the outside and exhaust air dampers modulate closed, and returnair damper modulate open to try to raise the supply air temperatureup to 55F?

Set the mixed air temperature reading to 35F, to check for freeze protection.






Are the outside and exhaust air dampers fully closed, and return air damper fully open, to protect the coil against freezing?

Set the fire/smoke detection signal to ON.

Do the fans turn off?

Do the outside air and exhaust air dampers close?

Return the BAS and AHU to their normal operating modes, and release the OAT, SAT, MAT, and set point overrides.

Are the fans on?

Are the dampers in their expected operating positions based onoutside air and return air temperatures? Record the OAT and RAT.

For the SSC:

Set the supply air temperature set point to 55F.

Set the return air temperature to 72F.


Is the outside air damper at minimum, the return air damper full open,and the exhaust air damper closed?

Set the outside air temperature to 70F. Are the outside and exhaust air dampers full open and return air damper closed?

Set the mixed air temperature reading to 43F (below the minimummixed air temperature set point of 45F).

Do the outside and exhaust air dampers modulate closed, and returnair damper modulate open to try to raise the mixed air temperature up

to 45F?

Set the mixed air temperature reading to 35F, to check for freeze protection.

Are the outside and exhaust air dampers fully closed, and return air damper fully open, to protect the coil against freezing?

Set the fire/smoke detection signal to ON.

Do the fans turn off?

Do the outside air and exhaust air dampers close?

Return the BAS and AHU to their normal operating modes, and release the OAT, SAT, MAT, and set point overrides.

Are the fans on?

Are the dampers in their expected operating positions based onoutside air and return air temperatures? Record the OAT and RAT.

Both Cases:

Set the BAS to heating mode.

Does the outside air damper go to its minimum position?

Is the exhaust damper closed and the return damper full open?

Return the BAS to its normal operating mode.

The checklist items are all successfully completed. ___ YES ___ NO







# COMMENT






XI. FUNCTIONAL TESTS - ECONOMIZER PERFORMANCE TEST

Instructions: This functional/performance test augments the manufacturer’s instructions, and is to be performed when the system is operational. Fill in the appropriate values if other information is requested, such as damper position (%) or

temperature. Identify responsible contractor.







SSC AHU2

SSC AHU3

PEC AHU1

Contractor

Value/

Comments

Mixing Box Performance Test

Perform the following stratification test in cold weather. The outside air temperature should be below 40°F and the outside air damper should be

at its minimum opening. Repeat the measurements during minimum and maximum supply air flow rate conditions.

Measure the air temperature profile upstream of the filter. Take a

temperature measurement at the center of each square yard of filter area.

Record the mixed air temperature from the ECMS.

Determine the difference between the minimum and maximumtemperatures.

Is the difference between the minimum and maximum temperatures lessthan 5°F?

Average all of the temperatures for each profile.

Is the difference between the ECMS mixed air temperature and the

average profile temperature less than 3°F?

Notes to Economizer Performance Test:

Comments, notes, deficiencies:






XII. FUNCTIONAL TESTS - ECONOMIZER OPERATIONAL TREND TEST

Test Procedure: Trends are useful for verifying that the economizer is operating properly when the commissioner cannot be present (such as

evenings, weekends, or extended periods of time). Following is a test procedure that will help verify proper operation of the economizers under

normal system control. Trend graphs are produced which can be used to check that sequences of operation are followed. Economizer

temperatures will be logged for about two weeks. Plots will indicate if the AHU is scheduled correctly and if the economizer dampers are functioning properly. Follow the steps below for each economizer.

Criteria for Acceptance: Items #1 - 12 require answers of “Y” (or “NA”, where relevant) except where other criteria are noted.

Check Equipment-> SSC AHU

1

SSC AHU2

SSC AHU3

PEC AHU1

Contractor

Value/

Comments

Set up EMS trends or install temperature data logging equipment for the following measurements:

Supply Air Temperature – downstream of cooling coil, where air streamis well mixed

Mixed Air Temperature – as far downstream from the mixing dampers as possible without being too close to the cooling coils. A multipoint probe

may be useful for more accurate measurements.

Return Air Temperature – upstream of the return air dampersOutside Air Temperature – place in a protected location near the outsideair grill, away from direct sunlight. If it must be placed in direct

sunlight, shield the sensor with aluminum foil, allowing air to flowaround the sensor, without touching the sensor.

Fasten the temperature sensors securely, and do not allow the sensors to

touch any surfaces.

Collect temperature data (and a timestamp) for a two-week period, whilethe HVAC system is in normal use. Try to capture a period of time with a

wide swing in operating conditions, or outside air temperatures. Storeinstantaneous data at 5-minute intervals.

Download all data into a spreadsheet, and line up all of the data with time.

Use a program such as PG&E’s Universal Translator (UT) if you need help lining up the data.

Plot all four temperatures versus time. Does the plot demonstrate the

following:

Hours of operation are limited to occupied building hours plus an hour or two before building occupancy.

With the AHU is running, does the mixed air temperature track theoutside air temperature when the outside air temperature is between the

supply air temperature and the return air temperature?

When the outside air temperature is above the return air temperature,

does the mixed air temperature track the return air temperature plus a few degrees (due to minimum outside air flow entering the air handler)?

When the outside air temperature is below the minimum supply air temperature set point, does the mixed air temperature stay close to theminimum supply air temperature set point.

Notes to Operational Trend Test:

1 Attach the time plots to this test form to document your test results.







XIII. FUNCTIONAL TESTS - M&V SAVINGS CALCULATION USING PERFORMANCE

TRENDING TESTS

Introduction: The following procedure should be used to estimate the savings due to improvements in economizer

performance. It follows ASHRAE’s retrofit isolation approach for determining M&V savings. The assumption is that other commissioning efforts do not affect the economizer’s performance or our estimate of savings. The improvements could come

from a commissioning effort on new or old equipment or from repair, replacement, or retrofit of existing equipment.

Measurements of pre- and post-retrofit data will be needed, in order to characterize the economizer’s performance

improvement as a function of outside air temperature. To determine the energy savings, a model of the fan supply air flow as

a function of outside air temperature will also be needed. The following procedure does not yet comply with ASHRAE 14P, since an uncertainty analysis of the results has not been performed, and we do not know if the results fall within the criteria

of the guidelines.

ASHRAE’s criteria for the application of the retrofit isolation approach involves the following steps:

1. Select independent variables and develop model

2. Select and document Baseline conditions

3. Select duration and frequency of monitoring for Baseline and Post Retrofit periods

4. Project Baseline usage to Post Retrofit conditions

Determine savings by: Savings = Projected Baseline (usage, demand) - Post Retrofit (usage, demand)

Test Procedure:

1. Set up and collect pre-retrofit performance trend data using the Economizer Operational Trend Test protocol

(above). Collect enough data to be able to model the economizer over as wide a range of ambient temperatures as

possible. We suggest several weeks of data collected during a transitional season, such as spring or fall. Preferred

baseline data would ideally cover a one-year period before the implementation of the ECM (energy conservation

measure), even though this is rarely achieved.

2. After the retrofit is completed, collect the same economizer data as well as supply fan RPM data. Data collected

during a wide range of outside air temperature conditions is preferable. Collect data for at least one month, for useas an estimate of the savings. Collect data for one year for use in determining ESCO payments or utility rebates.

3. Create a model of the “mixed air temperature minus what the MAT should be” versus outside air temperature, for

both pre- and post-retrofit data.

4. Using fan performance curves, estimate the fan flow (in lbs/hour) from the RPM data that was collected during the

post-retrofit period.

5. Create a model of the fan flow as a function of ambient temperature for the post-retrofit period, for when the

building was occupied.

6. If a full year of data is not available, estimate how much energy will be saved from short-term data in a normal year. Load TMY2 data for your site into a spreadsheet, and use the models to predict MAT deviations and supply airflows

using expected ambient temperatures.

7. Filter the ambient temperature data to include only data for when the building is occupied.

8. For each hourly reading of ambient temperature, calculate the energy saved due to the economizer retrofit, using

the following formula:

Energy saved(kWh) = [(MATdev pre – MATdev post ) * Supply Air Flow(lbm /hr) * 0.24 (Btu/lbm*F)] /






[12,000 (Btu/hr/ton) * Nominal Chiller Efficiency (kW/ton)]

For each economizer, follow this procedure for determining annual energy and dollar savings:

Criteria for Acceptance: The calculated estimate of monthly savings meets the required minimum level and range of uncertainty.

Check

Equipment->SSC

AHU1

SSC

AHU2

SSC

AHU3

PEC

AHU1

Contractor Value/

Comments

Sum up the hourly energy savings for the nominal weather year tocalculate the expected annual energy savings (kWh/yr).

If actual savings are to be determined for ESCO payments or utility

rebates, repeat the above calculation using actual monitored data (for one year of the post-retrofit period) and the model from the pre-retrofit

test period applied to the post-retrofit data.

To calculate the energy dollar savings, repeat the energy savingscalculation on an hourly basis, and apply actual electrical energy

rates (either TOU or other applicable schedule). Sum up the dollar savings for the year for an annual amount.

Calculate the uncertainty (and confidence interval) in the results using methods outlined in ASHRAE 14P.







XIV. COMMISSIONING REPORT OUTLINE:

Report: The following outline should be used to prepare the commissioning report for these economizers.

Executive Summary of Test Results

Commissioning Plan Outline

List Deficiencies Found

List Corrective Actions Taken

List Deficiencies that were not Corrected

Conclusions – How will remaining deficiencies be Corrected

Appendix A – Completed Test Protocols

Appendix B – Data Sheets

Appendix C – Performance Trend Plots






XV. REFERENCES USED TO DEVELOP THE ECONOMIZER PROTOCOL:

ASHRAE Proposed Guideline 14P, Measurement of Energy and Demand Savings. Post 1st Public Review. Atlanta, Georgia. January 17,

2001.

ASHRAE Guideline 1-1996, The HVAC Commissioning Process. Atlanta, Georgia. 1996.

Ellis, Rebecca and McKew, Howard. Back to Basics – Series V, Topic: Central Air with Return Air System. Originally printed in July,

August, and September 1997 issues of Engineered Systems.

Katipalumula, S.; Pratt, R.G.; et. al. Automated Fault Detection and Diagnostics for Outdoor-Air Ventilation Sysems and Economizers:

Methodology and Results from Field Testing. ASHRAE Transactions 1999, V. 105, Pt. 1.

Montgomery County, Maryland. Building Commissioning Program & Contractor Quality Control – Guidelines & Specifications. Paul

Tseng, Montgomery Engineering Institute, Division of Facilities and Services, Dept. of Public Works and Transportation. July 1998.

University of Washington, Commissioning Specifications, Facilities Services, Facility Design Information. Volume 2, Appendix 17C,

pages 1 to 27, Check-off Sheets: Air Handling Systems. September 1995.

Austin, S.B. HVAC System Trend Analysis. ASHRAE Journal page 44. February, 1997.

National Environmental Balancing Bureau (NEBB). Procedural Standards for Building Systems Commissioning. Gaithersburg,

Maryland. Section 6 and Appendix A pages 11.1.1 to 11.3.2. Rev 2.0, November 1999

Pacific Energy Center (Pacific Gas and Electric), Tool Lending Library, Toolbox. Assessing Economizer Performance. Website:

http://www.pge.com/003_save_energy/003c_edu_train/pec/toolbox/tll/app_notes/asses_econ.shtml . Ryan Stroupe (PEC).

Sacramento Service Center, Building A, HVAC System Renovation, Sequences of Operation, Johnson Controls, Date 7/27/99.

Pacific Energy Center, Draft Systems Manual, Sherrill Engineering (San Francisco, CA), Sections 1 and 3. April 2, 2001.

http://www.pge.com/003_save_energy/003c_edu_train/pec/toolbox/tll/app_notes/asses_econ.shtml

http://www.pge.com/003_save_energy/003c_edu_train/pec/toolbox/tll/app_notes/asses_econ.shtml

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