Senin, 12 April 2010

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 Unit
Richard 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 the California 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 this report 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.



Contents

General Commissioning Procedure for Economizers


FOREWORD ……………………………………………………………………….1
I. PROJECT / BUILDING DESCRIPTION………………………………………...2
II. SEQUENCES OF OPERATION………………………………………………...4
III. ACCEPTANCE AND RESPONSIBILITIES..………………………………….5
IV. VERIFICATION – CHECKS FOR REQUIRED DOCUMENTATION AND
TRAINING………………………………………………………………….6
V. VERIFICATION – NAMEPLATE DATA CHECKS…………………………..7
VI. VERIFICATION – INSTALLATION CHECKLIST………………………….10
VII. VERIFICATION – CONTROLS SENSOR CALIBRATION CHECKS..…...13
VIII. VERIFICATION – BALANCE REPORT CHECKS………………………. 14
IX. VERIFICATION – OPERATIONAL CHECKS
1) EXERCISE DAMPERS…………………………………………………15
2) FIRE ALARM ECONOMIZER DAMPER POSITIONS.………………17
3) ECONOMIZER MODE CHECKS………………………….…………...18
4) 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..26
XIII. FUNCTIONAL TESTS – M&V SAVINGS CALCULATION USING
PERFORMANCE TRENDING TESTS ……………………….……………….27
XIV. COMMISSIONING REPORT OUTLINE……………………………………29
XV. REFERENCES USED TO DEVELOP THE ECONOMIZER PROTOCOL…30

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 the two 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 Description
    Description of Systems Under Test
Equipment Covered by this Protocol
Sequences of Operation
Acceptance and Responsibilities
Verification Checks
Checks for Documentation and Training
    Nameplate Data Checks
    Installation Checklist
    Controls Sensor Calibration Checks
    Balance Report Checks
    Operational Checks -
        1) Exercise dampers
        2) Fire Alarm Economizer Damper Positions
        3) Economizer Mode Checks
        4) Controls Program Checks
Functional Tests
Forced Response and Sequence of Operation Testing – Fans On/Off, Morning Cool-down or Warm-up, Normal Operating Modes, Fire/Smoke Alarm, Freeze Protection
Economizer Performance Test
    Economizer Operational Trend Test
    M&V Savings Calculation using Performance Trending Tests – Outline of Procedure
References Used to Develop the Economizer Protocol
Results and Recommendations Report




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.


  1. 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 with typically 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.
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.




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 55°F to 65°F. 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 operating mode, 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 versus damper 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 
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 
Return 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 
Outside Air Damper Actuator 
As specified 
As submitted 
As installed 
Manufacturer 
Model # 
Serial # 
Type 
Electrical Data (i.e. signal range) 
Maximum Position 
Minimum Position 

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


DESCRIPTION 
Exhaust Air Damper Actuator 
As specified 
As submitted 
As installed 
Manufacturer 
Model # 
Serial # 
Type 
Electrical Data (i.e. signal range) 
Maximum Position 
Minimum Position 

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




DESCRIPTION 
Return Air Damper Actuator 
As specified 
As submitted 
As installed 
Manufacturer 
Model # 
Serial # 
Type 
Electrical Data (i.e. signal range) 
Maximum Position 
Minimum Position 

Comments on Nameplate Data Checks (add more sheets if needed):
#        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 AHU1 
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 specs and 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 have identical actuators and linkages to make each section's characteristics 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 thorough mixing 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 the application 
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 the directions 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 each other 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.
CONTROL TYPE 
CAL SENSOR LOCATION 
EMS SENSOR LOCATION. IS IT OKAY? 
EMS MEASURED
VALUE 
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) 
Specification and 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.


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 air handler, 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.


Enter "Y", "N", "NA", or data as requested. Enter comment or note number if deficient.
        Check                    Equipment->SSC AHU1 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%. 
Make sure that the scale is labeled to indicate the 100% position. 
Is return air damper fully closed? 
Is return air damper position indicator pointing to 0%. 
Make sure that the scale is labeled to indicate the 0% position. 
Command outside air damper to 0% open. 
Is outside air damper fully closed? 
Is outside air damper position indicator pointing to 0%. 
Make sure that the scale is labeled to indicate the 0% position. 
Is exhaust air damper fully closed? 
Is exhaust air damper position indicator pointing to 0%. 
Make sure that the scale is labeled to indicate the 0% position. 
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 outside air damper position indicator pointing to 20%. 
Make sure that the scale is labeled to indicate the 20% position. 
Is exhaust air damper at 20% open? 
Is exhaust air damper position indicator pointing to 20%. 
Make sure that the scale is labeled to indicate the 20% position. 
Is return air damper at 80%? 
Is return air damper position indicator pointing to 80%. 
Make sure that the scale is labeled to indicate the 80% position. 
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 any unusual noises or problems. 
Determine damper closing speed. 
Command the outside air damper to 0% open and record the time it takes to fully close. Note any unusual noises or problems. 
Record the time it takes for the exhaust damper to close and note any unusual 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. 
The checklist items are all successfully completed for given trade.    ___ YES ___ NO

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

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 air handler, 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.


Enter "Y", "N", "NA", or data as requested. Enter comment or note number if deficient.
        Check                    Equipment->SSC AHU1 SSC AHU2 SSC AHU3 PEC AHU1 
Contractor 
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? 
The checklist items are all successfully completed for given trade.    ___ YES ___ NO

Comments on Operational Checks (add more sheets if needed):
#        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 requested, such as damper position (%) or temperature. Identify responsible contractor.
Check Economizer Damper Responses in Different Operating Modes
This 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.

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 air handler, 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.


Enter "Y", "N", "NA", or data as requested. Enter comment or note number if deficient.
        Check                    Equipment->SSC AHU1 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 zone temperature. 
(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 zone temp 
(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. 
Verify that exhaust air damper is closed. 
(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. 
Verify that outside air damper is closed.
Verify that return air damper is open. 
Verify that exhaust air damper is closed. 
(For the SSC) Set the mixed air temp to 47F.  
(For the PEC) Set the supply air temp to supply air temp set point plus 2F. 
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.
The checklist items are all successfully completed for given trade.    ___ YES ___ NO

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

IX. verification - Operational checks – 4) Controls Program Checks

Enter "Y", "N", "NA", or data as requested. Enter comment or note number if deficient.
        Check                    Equipment->SSC AHU1 SSC AHU2 SSC AHU3 PEC AHU1 
Contractor 
Value/ Comments 
Have flow charts and/or other documentation of the software specific to the 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 the economizer 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 to 6:00P 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 before occupancy? 
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? 


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

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-outs are 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.

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 air handler, 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.


Enter "Y", "N", "NA", or data as requested. Enter comment or note number if deficient.
        Check                    Equipment->SSC AHU1 SSC AHU2 SSC AHU3 PEC AHU1 
Contractor 
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? 
Verify that outside air damper is closed. 
Verify that return air damper is open. 
Verify that exhaust air damper is closed. 
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. 
Outside damper is at minimum and exhaust damper is closed? 
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. 
Outside damper is at minimum and exhaust damper is closed? 
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? 
Set the outside 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 71F. 
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 return air damper modulate open to try to raise the supply air temperature up 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 on outside 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. 
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? 
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 minimum mixed air temperature set point of 45F). 
Do the outside and exhaust air dampers modulate closed, and return air 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 on outside 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

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

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 air handler, 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                    Equipment->SSC AHU1 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 maximum temperatures. 
Is the difference between the minimum and maximum temperatures less than 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 AHU1 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 stream is 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 dampers 
Outside Air Temperature – place in a protected location near the outside air grill, away from direct sunlight. If it must be placed in direct sunlight, shield the sensor with aluminum foil, allowing air to flow around 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, while the HVAC system is in normal use. Try to capture a period of time with a wide swing in operating conditions, or outside air temperatures. Store instantaneous 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 the outside 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 the minimum supply air temperature set point.


Notes to Operational Trend Test:
1 Attach the time plots to this test form to document your test results.
Comments, notes, deficiencies:                                                                                                                                                                 

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.


  1. 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 use as an estimate of the savings. Collect data for one year for use in determining ESCO payments or utility rebates.


  1. 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.


  1. Using fan performance curves, estimate the fan flow (in lbs/hour) from the RPM data that was collected during the post-retrofit period.


  1. Create a model of the fan flow as a function of ambient temperature for the post-retrofit period, for when the building was occupied.


  1. 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.


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




  1. For each hourly reading of ambient temperature, calculate the energy saved due to the economizer retrofit, using the following formula:
    Energy saved(kWh) = [(MATdevpre – MATdevpost) * 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 AHU2SSC AHU3 PEC AHU1 
Contractor 
Value/ Comments 
Sum up the hourly energy savings for the nominal weather year to calculate 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 savings calculation 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.


Comments, notes, deficiencies:                                                                                                                                                                 


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.
 

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