IEA Annex 40               CITE-AHU:               An Automated Commissioning Tool for CAV               Air-Handling Unit...
CITE-AHU Commissioning of the Installation and Technical Equipment             -Air Handling Units Outline   n   Commissio...
AHU Commissioning Process (from CTPL)    Step 1: Design Review-      check control logic, sensor placement and sensor accu...
Automation of functional test scripts      1. Verify communications link      2. Run pre-coded test sequence from library ...
Procedure for Cx Analysis     CAV   1.   Import test data     VAV           2.   Specify data relationships           3.  ...
Expert rules-             AHU Performance Assessment Rules (House)             • Enhanced for constant air volume systems ...
Commissioning the ARIA BuildingStep 1 Design Review: AHU3     ¨ Design Review     ¨ Manual Cx     ¨ Automated Cx          ...
Step 2 Operator Interview: Mr. Laurent Auriaun   Candid w/ good knowledge of (undocumented) system history. UNIT      PROB...
Step 3 Installation Review and Verification                                       Outdoor Air Temp. Sensor                ...
Step 4 Forced Response Testing and Analysis(passive w/ BEMS)        UNIT PROBLEM DESCRIPTION &                            ...
Step 3 Forced Response Testing and Analysis (active w/ BEMS)First Auto Cx tests were conducted on AHU3 over two nights    ...
Step 3 Forced Response Testing and Analysis (active w/ BEMS)AHU2 Cooling coil capacity step test:   Return Temp. setpoint ...
To-Date Results      Unit     Fault                                          Solution                                     ...
To-Date Results, cont’dUnit         Fault                                                       SolutionAHU2,     AHU2 is ...
Gas Savings EstimateCorrect the boiler control logicn Boiler plant ran 24/7 to avoid occupant discomfort.n The control log...
Electrical Energy Savings EstimateCorrect scheduling errors       Annual estimate:for AHUs and pumps              4141€ ? ...
Conclusionsn   Some adaptation required for new systemsn   CITE_AHU detected 3 faults in 4 automated tests         n   Sch...
Future developmentn   Define specific test scenarios (with user-changeable parameters)n   Integrate test scenarios into CI...
Upcoming SlideShare
Loading in …5
×

Seminar58 castro presentation_3

161 views
140 views

Published on

Published in: Business, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
161
On SlideShare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
3
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Seminar58 castro presentation_3

  1. 1. IEA Annex 40 CITE-AHU: An Automated Commissioning Tool for CAV Air-Handling Units Natascha Castro, NIST Hossein Vaezi-Nejad, CSTB
  2. 2. CITE-AHU Commissioning of the Installation and Technical Equipment -Air Handling Units Outline n Commissioning Process n Development of CITE-AHU ¨ Test automation ¨ Expert rules ¨ Interface n Commissioning the ARIA Building ¨ Design Review ¨ Manual Cx Results ¨ Automated Cx Results n Savings Estimate/ Payback n Conclusions 2
  3. 3. AHU Commissioning Process (from CTPL) Step 1: Design Review- check control logic, sensor placement and sensor accuracy.M not currently emphasized in protocolsA Step 2: Operator Interview-N for existing buildings, ask building operator whether the air handlingU units are operating properly to the best of their knowledge. iterative!AL Step 3: Installation Review and Verification- conduct a field inspection to determine installed characteristics of theB equipment including condition and sensor availability update documentsEM Step 4: Forced Response Testing and Analysis-S complete passive testing with BEMS, before active testing manipulate the system under test by means of setpoint changes and sensor overrides. Document along with mode changes. Evaluate data for compliance. 3
  4. 4. Automation of functional test scripts 1. Verify communications link 2. Run pre-coded test sequence from library Value Displays as READ is completed This is the line number to input to change reference value 4
  5. 5. Procedure for Cx Analysis CAV 1. Import test data VAV 2. Specify data relationships 3. Specify system functionality 4. Analyze using modified APAR rules 5. Compare to archived tests for On-going CxCITE-AHU 5
  6. 6. Expert rules- AHU Performance Assessment Rules (House) • Enhanced for constant air volume systems • Considers additional equipment (heat recovery)CITE-AHU CITE -AHU Provides greater transparency of rule logic (tool tips ) 6
  7. 7. Commissioning the ARIA BuildingStep 1 Design Review: AHU3 ¨ Design Review ¨ Manual Cx ¨ Automated Cx n Serves Offices & Converted space n 100% outdoor air n Modes: ¨ Heating ¨ Free cooling w/ Heat recovery & Manual Bypass 7
  8. 8. Step 2 Operator Interview: Mr. Laurent Auriaun Candid w/ good knowledge of (undocumented) system history. UNIT PROBLEM DESCRIPTION AHU3 Zones partitioned for office spaces w/o changing ventilation configuration General Cannot change the controllers schedule, setpoints revert to a nightly shutoff at midnight and 05:00 startup ... 8
  9. 9. Step 3 Installation Review and Verification Outdoor Air Temp. Sensor 9
  10. 10. Step 4 Forced Response Testing and Analysis(passive w/ BEMS) UNIT PROBLEM DESCRIPTION & EFFECT ALL System schedule in override. (Controls installer left test s t Auto-Cx testing First Auto-Cx test of AHU3 TRA AHU3 program active) 30 2 1 2d n Auto-Cx testing TSA AHU3 period without fault period with fault TOA 25 1 am 4 am 1m a 4 am UHC AHU3 Supply Fan 20 1 15 Temp (°C) Cmd 0-1 10 0 5 0 06/10/2003 07/10/2003 07/10/2003 07/10/2003 07/10/2003 07/10/2003 08/10/2003 08/10/2003 08/10/2003 19:12 00:00 04:48 09:36 14:24 19:12 00:00 04:48 09:36 -5 1- 10
  11. 11. Step 3 Forced Response Testing and Analysis (active w/ BEMS)First Auto Cx tests were conducted on AHU3 over two nights 1st night- Fault free with 2nd night- Faulty condition BEMS pumps in manual override logic error causes pumps to cycle off First Auto-Cx test of AHU3 30 2 TRA AHU3 1s t Auto-Cx testing 2nd Auto-Cx testing TSA AHU3 period without fault period with fault TOA 25 1 am 4 am 1 am 4 am UHC AHU3 Supply Fan 20 1 Temp (°C) Cmd 0-1 15 10 0 Finding: 5 Cooling coil is undersized for 17°C (62.6°F). **Laboratory needs are not met- fan coil units added. 0 06/10/2003 07/10/2003 07/10/2003 07/10/2003 07/10/2003 07/10/2003 08/10/2003 08/10/2003 08/10/2003 19:12 00:00 04:48 09:36 14:24 19:12 00:00 04:48 09:36 -5 -1 11
  12. 12. Step 3 Forced Response Testing and Analysis (active w/ BEMS)AHU2 Cooling coil capacity step test: Return Temp. setpoint is changed from 20°C -> 19°C (3 hours) -> 18°C (3 hours) -> 17°C (3 hours) . Tra,s AHU2 Auto-Cx test of AHU2 Tra AHU2 Auto-Cx testing Auto-Cx testing period Tsa AHU2 25 period without fault. w ith fault.Tra,s not 1.5 Ucc AHU2 23 1 21Temp (°C) Cmd 0-1 19 0.5 17 0 Finding: Cooling coil is undersized for 17°C (62.6°F). 15 **Laboratory needs are not met- fan coil units added. 13 -0.5 1/22/2004 1/22/2004 1/22/2004 1/22/2004 1/23/2004 1/23/2004 1/23/2004 14:24 16:48 19:12 21:36 0:00 2:24 4:48 12
  13. 13. To-Date Results Unit Fault Solution Automate damper control based on AHU3 Operating with heat recovery in summer outdoor and return air temperatures AHU1, Outdoor air temperature Provide sensor shading 2 and 3 Return air temperature sensor is located Correct the location of the return air AHU1,2 downstream of the outdoor air supply duct temperature sensor Supply air temperature setpoint (21°C), Reduce supply air temperature setpoint AHU 3 results in nighttime heating in summer in summer Boilers Boilers in manual override in summer Apply summer schedule Chiller Condenser is 50% fouled Clean condenser fins Exhaust duct from AHU1 is connected to the Redesign exhaust system for AHU 1 AHU1,3 exhaust of AHU 3 and update design drawings AHU3 Nighttime shutdown not in effect Shutdown system 12 am - 5 am AHU1, Forced continual operation of AHUs due to a Remove test program 2 and 3 test program installed in 2000**Green= Manual Cx Blue= Bems Assisted Cx **Orange= comfort Yellow= energy 13
  14. 14. To-Date Results, cont’dUnit Fault SolutionAHU2, AHU2 is set for 24 hour operation which does not match the Synchronize equipmentChiller operation of the chilled water pumps, stopped 12am-7am operation The cooling coil of AHU1 was added after the construction of the building and is connected directly to the chiller Add a dedicated pumpAHU1 (without a separate pump) It is not possible to suspend for cooling coil delivery of cooling water to this AHU Boilers operate even when commanded off (pumps shut Force at least one boilerBoilers down, boilers still operate) to stop Ensure that the AHU3 circulation pump cycles with the boiler. The heating circulation pumpAHU3 coils are not supplied with hot water when the boilers cycle off. operates independent of the boiler. Reduce the open period The open period of the boiler isolation valves (3 mn) is tooBoilers of the boiler isolation long for the on/off period of the boilers (2mn) valves to 1mnAHU2 Return air temperature sensor reading does not match Replace faulty temp overlay sensor, system sensor is faulty. sensor 14
  15. 15. Gas Savings EstimateCorrect the boiler control logicn Boiler plant ran 24/7 to avoid occupant discomfort.n The control logic error was corrected January 5, 2004. ¨ improved comfort for occupants ¨ decreased gas consumption ¨ increased protection of the boiler plant equipment. Weekly Gas Consumption vs Mean Outdoor Temp (C) Winter Season Estimate: 700€ ?10% Gas Energy Savings 15
  16. 16. Electrical Energy Savings EstimateCorrect scheduling errors Annual estimate:for AHUs and pumps 4141€ ? 47% Electrical Energy Savings Energy Energy Energy Cost Power Equipment use before use after savings savings (kW) Cx (kWh) Cx (kWh) (kWh) € Fan AHU 2 2.2 19219 8580 10639 798 Fan AHU 3 8 69888 33280 36608 2746 Pump AHU & FCU (HW) 0.4 3494 1664 1830 137 Pumps Zone 1,2,3 0.067 585 279 307 23 x 3 Pump Zone 4 (HW) 0.047 410 196 215 16 Pump Zone 5 0.169 1476 703 773 58 Pump AHU & FCU (CW) 0.825 7207 3432 3775 283 Pump Zone 4 (CW) 0.1 873 416 457 34 16
  17. 17. Conclusionsn Some adaptation required for new systemsn CITE_AHU detected 3 faults in 4 automated tests n Scheduling errors (€) n Cooling Coil & Heating coil Undercapacity n Boilers sequencingn Development of automated tools must be used in conjunction with good protocol for system design reviews ¨ Limitations to automated testing (i.e., detecting sensor placement errors)n Quantitative energy benefits ¨ Excludes service requests Total gain 5000 € ¨ Equipment life Project cost 15000 € ¨ Heat recovery Pay back 3 yearsn Non-quantitative benefits also achieved- comfort, operator knowledge, maintenance, documentation 17
  18. 18. Future developmentn Define specific test scenarios (with user-changeable parameters)n Integrate test scenarios into CITE_AHU interfacen Automate documentation of test results ¨ Incorporate required manual test and documentation archiven Test VAV systems, Expand for other configurationsn Investigate Manufacturer interest to provide integrated package. Questions? 18

×