Memorial Student Center Complex (Bldg. 454)

Transcription

1 ontinuous ommissioning Assessment eport For Memorial Student enter omplex (Bldg. 5) By henggang Liu David E. laridge, Ph.D., P.E. omer L. Bruner, Jr., EM ontact: David E. laridge ( ) omer L. Bruner, Jr. ( ) March, 005

2 able of ontents Building Introduction and Description... MS Main and Food Service... Introduction... Building VA Systems... Energy Baseline and Metering... Existing VA onditions and Optimization...7 ommissioning Activities...8 hilled Water and ot Water System Balance...8 Verification of Zone eheat...9 roubleshooting...9 ecommendations...0 Energy omsumption Analysis...0 MS Annex... Introduction... Building VA Systems... Energy Baseline and Metering...5 Existing AU Operation and Optimization...7 ommissioning Activities...9 hilled Water and ot Water System Balance...0 Verification of Zone eheats...0 roubleshooting...0 ecommendations... Energy onsumption Analysis... MS otel... Introduction... Building VA Systems... Energy Baseline and Metering... Existing AU and FU onditions and Optimization... ommissioning Activities... Verification of erminal Box Operation... hilled Water and ot Water System Balance... ecommendations... Appendix A: AU s... Appendix B: Part List...7 Appendix : otel FU ondition...77

3 Building Introduction and Description he Memorial Student enter omplex is a two-story building with a basement and a total gross area of 8,000 ft. Located on the Main ampus of exas A&M, this building was originally constructed in 950. For the purpose of this report, the original construction of the MS complex is called the MS Main. Other parts of the complex include the Board of egents, the MS otel, and the MS Annex. he MS Main consists of multiple offices and student organization areas as well as ballrooms, a food service area, food courts, bookstores, and meeting rooms and areas. he MS Main has been renovated multiple times since its original construction in order to accommodate the needs and desires of the student body and faculty. he MS Annex was constructed in 989 to meet the demands of a growing student population and includes art galleries, a convenient store, a new entrance to the MS, and a crosswalk with offices to connect the MS to udder heater. he MS otel was constructed 950 as part of the MS Main building and has three floors, two floors of rooms where guests to A&M can stay and the first floor is the reception area. he Board of egents is connected to the MS omplex and is detailed in separate report. his report will cover the MS Main, MS Annex, and the MS otel. Figure : Front entrance to MS omplex Major ontinuous ommissioning for the MS omplex began /5/00 and ended /8/005.

4 MS Main and Food Service Introduction he MS Main is a two-story building with a basement and was constructed in 950 and has a total conditioned floor area of 00,0 square feet. Since its beginnings, the MS has been through numerous renovations and expansions to accommodate the needs of the student body. he VA (eating, Ventilation, and Air onditioning) system for this building consists of 7 air handling units (AUs). hese units are located in numerous mechanical rooms in the building and few are located in the ceilings of the different floors. All but two of these units are pneumatically controlled to maintain the space temperature setpoint. he primary pump room for the remaining MS is located in the basement where the MS Main, Food Services and Board of egents chilled water and hot water pumps are located. For the MS Main, there are three chilled water pumps which are equipped with variable frequency drives (VFDs). One of these pumps serves the Food Services area of the MS Main while the other two serve the MS Main. here are two hot water pumps for the MS Main which are constant speed pumps. One pump serves the Food Service area of the MS Main and another serves the remaining MS Main area. he pumps which serve the MS Main area (not the Food Service area) also serve the MS otel. Building VA Systems he MS Main building consists of 7 AUs, all of which are pneumatically controlled, except units. hese two units are equipped with Direct Digital ontrol (DD). Many of the AUs are single duty, couple controlled or multi-zone units. For the single duty units, a local thermostat controls the heating and cooling control valves with one signal in order to maintain the zone temperature set point. here is typically a dead band between the chilled water and hot water control valve signal to prevent simultaneous heating and cooling. owever, there could be some simultaneous heating and cooling if humidity needs to be controlled. AUs,,,, 0-9,, and 5 are all single duty units with a cooling and then heating coil arrangement as seen in figure, below. All of these units are couple controlled with a local pneumatic thermostat. able shows the locations served by these AUs. 5 7 o Space Figure : Schematic for AUs,,,, 0-9,, and 5 able : Serving areas for single duty AUs in the MS Main AU- Bookstore SD AU- Accounting SD AU- Exchange st Floor SD AU- Post Office SD AU-0 Banquet oom SD

5 AU- Banquet oom SD AU- Banquet oom SD AU- Banquet oom SD AU- Banquet oom SD AU-5 Banquet oom SD AU- Banquet oom SD AU-7 Banquet oom SD AU-8 Servery SD AU-9 Basement Offices SD AU- Ballroom SD AU-5 Ballroom SD AUs, 8, 0,,, 5-9, 0-, and existing,, and are all multi-zone units with a main cooling coil. eheat coils are located in each terminal box for the zones. A temperature sensor controls the discharge temperature of the AU while a thermostat controls its terminal box for reheat. Figure, below, shows a schematic for these units. able shows the locations served by these units in the MS Main. 5 o Zones Figure : Schematic for AUs, 8, 0,,, 5-9, 0-, and existing - able : Serving areas for multi-zone AUs in the MS Main AU- hoir Lounge MZ AU-8 Food Services Stock MZ AU-0 Dining all MZ AU- Former Students MZ 8 AU- orridors st Floor MZ AU-5 orridors st Floor MZ AU- Browsing Library MZ AU-7 MS Offices MZ 7 AU-8 orridors nd Floor MZ AU-9 Student Lounge MZ AU-0 st Floor otel MZ 5 AU- Basement rafts MZ 5 Basement AU- adio/photo MZ

6 AU- existing# existing# existing# Located in base. Mech. oom MZ 0 AU, shown in figure, is a single duty unit with cooling only and serves the electrical and equipment room located in the basement in room 0. A thermostat located in the return air stream controls the cooling control valve to maintain the return air temperature at its setpoint. o Space Figure : AU schematic AU 9 is a multi-zone unit with a preheat coil and then a cooling coil as detailed in figure 5. his unit is a 00% fresh air unit and serves the kitchen area for the MS Main. he preheat and cooling coils are controlled by a discharge air temperature sensor. Local thermostats control the terminal reheat control valves. P 5 o Zones Figure 5: AU 9 schematic Detailed in figure is AU MB-5, which is a multi-zone unit with an outside air preheat and a mixed air cooling coil. eheat coils are located in the terminal boxes for each zone. his unit serves the ullabaloo food court located in the basement of MS Main. When the MS Annex AUs were update with Direct Digital ontrol (DD), AU MB-5 was updated with DD control as well. his is a constant speed unit and a temperature sensor controls the discharge temperature of the unit. he discharge temperature setpoint is based on outside air temperature which can be seen in table. he outside air preheat coil maintains a discharge temperature of 5 F. he space temperature setpoint is 70 F.

7 P 5 o Zones EMS Figure : AU MB-5 schematic able : AU MB-5 old Deck Schedule Outside Air emp. ( F) Discharge Air emp ( F) 5 55 AU M- hangs in the ceiling of the food catering area and serves this area as well. It is equipped with DD control and is a single duty unit with heating and then cooling. Figure 7 shows the schematic for this unit. 5 o Space Figure 7: AU M- schematic he three chilled water pumps for the MS Main are equipped with VFDs to control the pump speed. he pump speeds are maintained to control the loop differential pressure (DP) at its setpoint, which is constant as set by the user. he two hot water pumps, one for the MS Main and one for the MS Main Food Service, are constant speed pumps. he DP setpoint for these two loops is maintained by modulating their building control valve located in the return line of the two loops. he MS Main hot water control valve is modulated by he MS Food Service hot water control valve is modulated by.. Figure8 and 9, below, show the chilled water and hot water loops for the MS Main. Building eturn Primary eturn Primary Building MS Main 5 Food Service Figure 8: hilled water loop for the MS Main and Food Service

8 Building eturn Primary eturn Primary Building MS Main Food Service Figure 9: ot water loop for the MS Main and Food Service Energy Baseline and Metering he baseline energy consumption was measured between January, 00 and December 00. Figures 0 and below show the chilled water and electricity energy consumption. he hot water consumption was missed in the data base, shown hw onsumption (MMBut/r) /0/0 0/9/0 0/0/0 05/09/0 0/8/0 08/7/0 0/0/0 /5/0 0//0 Date Figure 0: hilled water consumption before

9 Eletricity onsumption (KW) /0/0 0/9/0 0/0/0 05/09/0 0/8/0 08/7/0 0/0/0 /5/0 0//0 Date Figure : hilled water consumption before Existing VA onditions and Optimization Prior to implementing measures, measurements were taken on the building VA system. his included measurement on the AUs, pumps, and exhaust fans. If needed, these measurements were also compared to EMS readings to verify and calibrate sensors. Also, the existing control programs in EMS were reviewed. hese measurements were then used to determine a baseline for the existing building condition and comfort. All of the AUs were in fair operating order. owever, there were 9 bad chilled water and hot water control valves found. he bad control valves can cause an increase in energy consumption when they stick in the open position. For a list of these malfunctioning control valves, see Appendix B. For AUs 0 through 8 which are located in the ceiling above the ballrooms and serve the ballrooms, three fresh air supply fans were not functioning. hese fans supply,75 cfm of outside air to the mechanical room located in the ceiling above the ballrooms. By repairing these fans, the comfort conditions in the ballrooms will improve. Also, the electricity energy consumption will increase. he water systems for the MS Main consist of chilled water pumps and two hot water pumps. he MS Main area has two chilled water pumps where one is constant speed and the other is equipped with a VFD. he chilled water pump for the Food Service is equipped with a VFD as well. Both hot water pumps, one for the MS Main and one for Food Service, are constant 7

10 speed. he chilled water pumps which are equipped with VFDs have their DP setpoints controlled by operator input. he setpoint for the MS Main area pumps is 5 psi and 8 psi for the pump which serve the Food Service. hese setpoints were reset during the commissioning process. See the chilled water and hot water system balance section for details. Since all of the AUs in the MS Main are pneumatically controlled, none of them are equipped with VFDs, and many of the units are multi-zone units, there is little opportunity to for optimization. For the multi-zone AUs, the discharge temperature setpoints were adjusted if necessary. Some of the discharge setpoints were below 55 F, which is unnecessary, and were reset to 55 F. Several sensors were found out of calibration and were calibrated as well. For all of the AUs, every control valve was check to ensure sound operation. If needed, the spring range was adjusted (if the spring range was incorrect by several psi). ommissioning Activities ommissioning activities included the measuring of all AUs for airflows and temperatures. Also, the chilled and hot water pressures and temperatures before and after the coils were measured for each AU. hese measurements were used to diagnose any problems with the air handlers. hese measurements were also used to verify and calibrate local sensors, if needed. Other mechanical inspections were conducted as well such as checking dampers, filters, fan belts, control valve operation, and fan operation. Also, cooling and heating coils in the units were cleaned and the waterside was back flushed. Water pressures and temperatures were also taken before and after the pumps, as well, to diagnose any problems and verify and calibrate sensors. Local thermostats were also calibrated if needed and control valve spring ranges were verified and adjusted as needed. hilled Water and ot Water System Balance here are two chilled water pumps for the MS Main area, where one pump has a VFD while the other is a constant speed pump. he chilled water pump for Food Service is equipped with a VFD. he chilled water control valves for both loops are DD controlled by Siemens. he building DP setpoint for both loops is a constant value which is specified by the operator. For the MS Main, this DP setpoint is 5psi, for the Food Service, this setpoint is 8psi. Measuring the DP for the last AU on each loop to be psi, it was determined that a building DP setpoint for the MS Main should be psi and psi for the Food Service when the outside air temperature was 0 F. From this information, the MS Main building chilled water DP setpoint is calculated from table. hese DP setpoints are calculated based on outside air temperature rather than flowrate because only the MS Main building has a flow meter which includes the MS Main, Food Service, and Board of egents. able : MS Main building chilled water DP setpoint Outside emp. ( F) MS Main DP setpoint (psi) Food Service DP setpoint (psi) here are two hot water pumps for the MS Main. One pump is for the MS Main area while the other is for the Food Service. Both pumps are constant speed. he hot water building control valve for the MS Main is on DD control but is not being control and is 00% fully 8

11 open. he building hot water control valve for the Food Service is pneumatically controlled to maintain a supply temperature of 50 F. For the MS Main, the hot water control valve should modulate to maintain a hot water supply temperature setpoint as detailed in table 5, below. able 5: MS Main building hot water temperature setpoint Outside emp. ( F) MS Main W supply temp ( F) For the MS Main, the chilled water pump equipped with a VFD (pump #) will run to maintain the DP setpoint as set by the operator. When the speed of chilled water pump # increases above 95%, the constant speed chilled water (pump #) will turn on. hilled water pump # will then decrease its speed to maintain the DP set point. Once pump # falls below 70% speed, pump # will turn off. able : MS chilled water measurements Primary Primary eturn Food Services eturn 9 MS Main eturn Food Services MS Main emperature ( F) emp Sensor N/A 5.5 N/A.78 d emp Pressure Sensor d Pressure able 7: MS hot water measurements Primary Primary eturn Food Services eturn MS Main eturn Food Services MS Main emperature ( F) emp Sensor..97 N/A 8.89 N/A N/A d emp.5 N/A 0 N/A N/A Pressure Sensor. 5.9 N/A N/A N/A N/A d Pressure 9 N/A N/A N/A Verification of Zone eheat All of the terminal reheats were checked for sound operation. his included checking reheat valves and reheat coils. All of the coils were also cleaned on the air side and back-flushed on the water side. All of the control valves were check for proper working order. Appendix B details the bad control valves for the MS Main. roubleshooting he north office area of the nd art gallery in the MS was cold on the second floor. Upon investigation, this art gallery and office area is served by two zones from the respective AU. owever, portions of the office area and gallery are served by both zones. he reason the office was cold was that the gallery contained art work which required the space temperature to be 8 F. hese zones cannot be balanced. In order to solve the long term problem, the office area and the gallery need to be on separate zones.

12 oom 0 was cold. his was due to a manual hot water valve being shut and there was no reheat to the zone. his hot water valve was opened and the local system was checked to ensure there were no leaks. he room temperature increased from 8 F to 7 F. In the Singing adets area, a pneumatic air line meandered in an out of an office near a reheat coil and was not terminated. his line did not have any air pressure in it. A reheat valve located outside of the Singing adets offices had a main air line connected to it. hus, there was no reheat from this coil. his coil serves an area between the bowling and games area and the ullabaloo eating area. It appears a thermostat should be installed in this location. he main air line could then connect to the thermostat and the free air line in the ceiling could connect to the thermostat and reheat control valve, thus controlling reheat for that zone. AU -, which hangs in the ceiling of the catering area, is running and blowing air but the proof is not on. his run proof is not functioning and needs to be corrected. ecommendations ) Install VFDs for the two hot water pumps which serve the MS Main and Food Service. ) Install pressure sensors for the MS Main in the hot water secondary supply and return lines. ) Install temperature sensors and pressure sensors for Food Service in both, the secondary supply and return lines and then convert the hot water control valve from pneumatic to DD control. ) For the nd floor art gallery, the north end offices and art gallery are supplied by the same two zone ducts. his causes the offices to be uncomfortable when the gallery needs to be maintained at a warmer or colder setpoint than the offices. One of these zone ducts needs to serve only the offices and the other needs to serve the art gallery. 5) eplace bad chilled water and hot water control valves on AUs, exhaust fan belt and motors. See Appendix B for detail. ) Install a reverse acting pneumatic duct-stat in the discharge air duct for AU-9 which serves the MS Flagroom. his is used to control the normally open chilled water control valve to maintain a discharge air temperature of 55 F. urrently, the control valve is controlled by the highest signal sent by the zone reheats. his part is on the list of Appendix B. Energy omsumption Analysis Since the chilled water and hot coils on these units were backflushed on the water side and washed and cleaned on the air side, energy consumption may increase while the bad valves are in place. By backflushing the coils, the water flow through the coils can be increased. By washing and cleaning the air side of the coils, the heat transfer to the air is increased and the airflow across the coil is increased. When the bad valves are replaced or repaired and controlling properly, energy consumption should decrease. Energy savings should be achieved when those bad control valves are replaced. 0

13 MS Annex Introduction he MS Annex was constructed as an addition to the MS Main building in 989 and has a floor area of 5,00 square feet. It houses a variety of commercial building applications including two art galleries, a bowling and billiards center, general administrative offices, a convenience store, and a copy center. here are three floor levels including the basement and a crosswalk and it is served by eight air handling units. able 8: MS Annex Air onditioned Floor Area Floor Area (sq. feet) Basement 900 st Floor 0870 nd Floor 570 otal 500 he lowest level of the MS annex is the basement. It has an air conditioned floor space area of,900 square feet and is served by four air handling units (AUs), MB, MB, MB, and MB. As can be seen in figure 0 below, the annex is bordered on the west side by the old pre-existing MS building and there are two mechanical rooms located at this level. Figures and show the floor layouts for the first and second floor of the MS Annex. he mechanical room located at the southeast corner of the building houses AU MB and the two hot and two chilled water pumps for the annex. Air andling Unit MB serves the bowling and games area of the MS. he northeast mechanical room houses AUs MB, MB, and MB. AU MB serves the shipping and receiving offices for the MS located at the basement level, AU MB serves the Singing adets offices and music areas in the basement, AU MB serves the Stark Gallery which is a two-story high art gallery located on the first floor. It also serves the art storage area in the basement. AU MB serves the bowling and games area located in the basement of the MS Annex. he mechanical room on the southeast corner of the first floor houses two units (AU - and -). AU - serves the entrance and lobby area of the MS Annex and AU - serves the convenient store area located at the entrance of the MS Annex. he mechanical room on the southeast corner of the second floor of the MS Annex houses AUs - and -. AU - serves bridge/crosswalk area which connects the MS Annex to udder heater. AU - serves the art and meeting areas located prior to and on the crosswalk. Building VA Systems All eight of the AUs serving the MS Annex are equipped with Direct Digital ontrol (DD) and are controlled through the Energy Management ontrol Systems (EMS). owever, all of the terminal reheats are all local pneumatic control. AUs MB- and MB-, as detailed in figure, are equipped with Variable Frequency Drives (VFDs) on their supply and a return air fans. hese VFDs are controlled through EMS to maintain the discharge static pressure and airflow rate setpoints. he return fan maintains a return air flowrate of 800 cfm less than the supply air flowrate. Also, via a temperature sensor on the discharge of the AU, EMS controls the cooling valve to maintain the discharge temperature at its setpoint. Local thermostats in the space control the VAV boxes and their reheat control valves.

14 Figure 0: MS Annex basement floor layout and serving area. Figure : MS Annex first floor layout and serving area.

15 Figure : MS Annex second floor layout and serving area. elief Air AMS VFD VFD 5 eturn EMS AMS o Zones Figure : AU MB and MB Schematic AU MB- serves the Stark Gallery and its art storage areas. his unit is detailed in figure below. he outside air for this unit passes through an outside air scrubber which consists of a damper, filters, and an outside air supply fan. he outside air fan is equipped with a VFD and is controlled by an outside air flow station to maintain the outside air flowrate at its setpoint. he return air comes from the gallery and the storage vault. here is a damper on the return duct from the storage vault which will close incase of a fire in the vault. he mixed air then passes through a set of two more filters. he supply fan is constant speed. After the supply fan, there is a double deck where air is blown through the cold deck and a bypass deck. Immediately after these two decks, the ducts are divided into zones. hen each zone duct is still divided into two sections, one for cold air and one for neutral air. A damper in each zone duct modulates to control the mixing of the two air streams to the zone. hese dampers are controlled through EMS to control the room temperature at its set point. Upon the mixing of the two air streams, the air is duct to each zone where terminal boxes reheat as called for by erminal Equipment ontrollers (Es). he cooling control valve on the cold deck is controlled by EMS to maintain a cold deck temperature setpoint or the humidity level in the space (whichever is greater).

16 s AMS 5 o Zone (ypical of zones) VFD EMS Figure : AU MB schematic he bowling and games area is served by AU MB-, which is detailed in figure 5, below. his unit is constant speed and a temperature sensor in the space controls the preheat and cooling control valves through EMS. his unit also equipped with a return fan as well as a supply air fan. elief Air P 5 EMS eturn o Space Figure 5: AU MB Schematic AU- and -, shown in figure, are single duty units with preheat and then cooling. A temperature sensor located in the space controls the preheat and cooling control valves through EMS. Also, this unit is a constant speed unit. AU - and - also operate on an economizer cycle when the outside air temperature is between 5 F and 5 F. owever, the outside air damper is not modulated. he damper is either in the minimum position or fully opened. During the economizer cycle, when the mixed air temperature is less than the discharge air temperature, the outside damper is in the minimum position and the damper is in the open position when the mixed air temperature is higher than the discharge air temperature. EMS P 5 o Space Figure : AU - and - schematic Figure 7, below, shows a schematic for AU -, which is a constant speed unit. A temperature located in space controls the preheat and cooling control valves through EMS. his unit also has a supply and a return air fan. AU -, shown below in figure 7, is cooling only and the supply and return air fans are equipped with VFDs. Air flow stations on the

17 discharge of the two fans control the fan speeds and a temperature sensor on the discharge controls the cooling control valve through EMS. Both of these units have an economizer cycle in which the outside air dampers modulate to maintain the mixed air temperature at its set point. For AU -, the mixed air temperature is 0 F and 55 F for AU -. elief Air P 5 EMS eturn o Space Figure 7: AU - elief Air AMS VFD VFD 5 eturn EMS AMS o Space Figure 8: AU - he pumps for the MS annex are located in the mechanical room behind the bowling and games area. his room is located in the southeast corner as shown in figure 0. here are two chilled water pumps and two hot water pumps and all are equipped with a VFD. All of the pump speeds are controlled to maintain the loop DP setpoint. Figure 9, below, shows the chilled water and hot water loops for the MS Annex. Building eturn Primary eturn Primary Building MS Annex Figure 9: Schematic for MS Annex chilled water and hot water loops. Energy Baseline and Metering he baseline energy consumption was trended from EMS between February, 00 and December 00. Figures 0 and below show the chilled water and hot water energy consumption. he electricity consumption was not available. 5

18 Figure 0: hilled water consumption before Figure : ot water consumption

19 Existing AU Operation and Optimization In 999, all of the AUs for the MS Annex were upgraded to DD control and can be monitored through EMS. Most of these units are single duty units which discharge into space and a temperature sensor controls the discharge air temperature. Some units serve office area where local pneumatic thermostats control the terminal reheat boxes. AU MB- is a multizone unit which serves the Stark Gallery. Due to this, this unit was handled carefully as to not disturb the gallery s room conditions. For these units, it is difficult to optimize the current system. Since there are no sliding schedules of static pressure setpoints or discharge air temperatures which vary with load, there can t be any resets implemented. For many of the units, only the space temperature and/or the discharge temperature sensor can be calibrated and the discharge temperature setpoint and room temperature setpoint can be changed. owever, these values can be changed through EMS easily by users in order to satisfy comfort conditions in periods of hot weather or malfunctioning parts. Discharge air temperature for AU - is set to control the space temperature at its setpoint. he space temperature setpoint is specified in the EMS control sequence and is currently maintained at a constant 7 F. his space sensor was calibrated as well since the sensor read 7 F while 9. F was measured in the field. AU - also operates on an economizer cycle when the outside air temperature is between 5 F and 5 F. owever, the outside air damper is not modulated. he damper is either in the minimum position or fully opened. During the economizer cycle, when the mixed air temperature is less than the discharge air temperature, the outside damper is in the minimum position and the damper is in the open position when the mixed air temperature is higher than the discharge air temperature. he preheat temperature setpoint for this unit is F lower than the space temperature setpoint. AU - serves the convenient store area at the east entrance of the MS omplex. his unit operates on an economizer cycle where the outside air dampers modulate to maintain a mixed air temperature of 0 F when the outside air temperature is below 5 F, otherwise, the damper is in the minimum position. Via EMS and a space temperature sensor, the preheat and chilled water control valves are modulated to maintain the space temperature setpoint which is currently a constant 70 F. he preheat temperature setpoint for this unit is F lower than the space temperature setpoint. he discharge air temperature for AU - is set to control the space temperature at its setpoint. he space temperature setpoint is specified in the EMS control sequence and is currently maintained at a constant 5 F. his setpoint needs to be reset to 70 F. he preheat temperature setpoint for this unit is F lower than the space temperature setpoint. AU - also operates on an economizer cycle when the outside air temperature is between 5 F and 5 F. owever, the outside air damper is not modulated. he damper is either in the minimum position or fully opened. During the economizer cycle, when the mixed air temperature is less than the discharge air temperature, the outside damper is in the minimum position and the damper is in the open position when the mixed air temperature is higher than the discharge air temperature. AU- serves the offices and the chilled water control valve is modulated to maintain the discharge temperature between 55 and 0 F. his discharge temperature is based on the discharge static pressure which ranges between 0. and 0.8inW. Zone reheats are modulated to maintain the space temperature setpoint. his unit also has an economizer cycle in which the outside air dampers modulate to maintain the mixed air temperature at its set point of 55 F when the outside air temperature is below 5 F. Otherwise, the damper is in the minimum position. 7

20 he VFD on this unit varies to maintain the end-of-duct static or the discharge static at its setpoint. AU MB serves the shipping and receiving offices for the MS located at the basement level. his unit has a constant discharge temperature setpoint of 55 F. he supply VFD varies to maintain the end of duct static pressure setpoint of.5inw or an air flowrate of 700 cfm. he return air fan speed varies to maintain a return flowrate which is 800 cfm less than the supply flowrate. Local thermostats control the terminal reheat boxes to maintain the zone temperature setpoint. he outside air damper is maintained at the minimum position. When a fire is detected and the halon sequence is initiated, the outside air damper will fully open. Setpoints with this unit s operation which can be optimized include a constant discharge temperature, a constant end of duct static, and the outside air damper position. he discharge temperature was reset according to outside air temperature and can be seen in table 9, below. able 0 shows the end of duct static reset based on outside air temperature. For the outside air damper, an economizer cycle was installed. When the outside air temperature is between 0 F and 5 F, the outside air damper is fully open. he damper will modulate to maintain a mixed air temperature F lower than the cooling setpoint when the outside air temperature is below 0 F. he damper will close to its minimum position when the outside air temperature is above 5 F. able 9: eset schedule for AU MB- discharge air temperature Outside Air emperature ( F) Discharge Air emperature Setpoint ( F) able 0: eset schedule for AU MB- end of duct static pressure Outside Air emperature ( F) End of Duct Static Pressure (inw) AU MB serves the Singing adets offices and music areas in the basement. his unit has a temperature setpoint which varies between 55 F and 0 F and local thermostats control the terminal reheats to maintain the room temperature setpoint. he discharge temperature setpoint will modulate between these temperatures based on the discharge air flowrate. he supply VFD varies to maintain the discharge static pressure of.5inw or the end of duct static pressure setpoint (which is calculated from the following equation), whichever requires a lower VFD speed: Equation : VFD based on end of duct static = (cfm/78) he return air fan speed varies to maintain a return flowrate which is 00 cfm less than the supply flowrate. he outside air damper is equipped with an economizer cycle. When the outside air temperature is below 5 F, the damper modulates to maintain a mixed air temperature equal to the discharge temperature setpoint. Otherwise, the damper is in the minimum position. AU MB- serves the Stark Gallery, its offices, and its storage vault. his unit has a VFD on its outside air intake fan in order to maintain a desired amount of outside air. he VFD on the outside air maintains the DP setpoint between the art gallery and the MS Flagroom or the air quality setpoint in the gallery, whichever is the maximum. owever, the maximum outside air flowrate is limited to 000 cfm. An air quality sensor located in the gallery would increase the outside air flow rate if the air quality rises above the setpoint level. he outside air damper is linked with the outside air fan and opens when the fan runs. eturn air to the unit is in two ducts. One duct is from the gallery area and the other is from the vault. he vault return air 8

21 is equipped with a damper which will close in case of a fire in the vault. hese dampers are tied into the halon system. he supply fan for MB- is constant speed. he supply air is passed through a double deck. One deck is a bypass and the other is the cooling deck, which has a discharge temperature setpoint based on the outside air humidity level. able below shows the cold deck discharge temperature with respect to outside air relative humidity levels. he two air streams are then divided into six zones. An interlocked damper in each zone duct modulates to mix the two air streams in order to maintain the zone temperature setpoint. he temperature setpoint for each zone can be seen in table, below. If this cannot maintain the room temperature setpoint, a terminal reheat control valve for the zone will open and modulate. If the humidity level in the zones rises above the zone humidity setpoint, the mixing damper in that zone duct opens fully to the cold deck and closes the bypass deck. he relative humidity level setpoint for the zones is 50%. Zone is the vestibule entrance to the Stark Gallery and has only temperature control and no humidity control. Zones,,, and 5 are the gallery and zone is the storage vault in the basement. able : AU MB- cold deck setpoint based on outside air relative humidity. Outside Air elative umidity (%) old Deck Air emperature Setpoint ( F) able : Zone temperature setpoints Zone Number 5 Zone emperature Setpoint ( F) urrently, the discharge air temperature of the cold deck is based on outside air relative humidity. his causes excessive chilled water use when the outside air temperature is low and the zones relative humidity is much lower than the setpoints of 50%. his low zone relative humidity feels dry to the occupants of the room. he cold deck temperature setpoint should be based on outside air temperature in order to maintain the zone temperatures as shown in table. If any zone s relative humidity rises above the setpoint of 50%, the cold deck control valve will open to maintain the zones relative humidity rather than temperature. A % dead band would be implemented in this control. able : eset schedule for AU MB- cold deck Outside Air emperature ( F) Discharge Air emperature Setpoint ( F) AU MB- serves the bowling and games area located in the basement. A temperature sensor in the space controls the preheat and cooling control valves to maintain the space temperature. he space temperature setpoint is 7 F. his is a constant setpoint which is inputted into EMS. When the outside air temperature is greater than 5 F, the outside damper is closed to the minimum position. Otherwise, the damper is modulated to maintain a mixed air temperature of 0 F. he preheat deck setpoint is set to be F lower than the space temperature setpoint. With a space temperature setpoint of 7, the preheat setpoint is 9 F. ommissioning Activities ommissioning activities included the measuring of all AUs for airflows and temperatures. Also, the chilled and hot water pressures and temperatures before and after the coils were measured for each AU. hese measurements were used to diagnose any problems with the air 9

22 handler. hese measurements were also used to verify and calibrate local sensors, if needed. Other mechanical inspections were conducted as well such as checking dampers, filters, fan belts, control valve operation, VFD speed, and return fan operation. Also, cooling and heating coils in the units were cleaned and the waterside was back flushed. Water pressures and temperatures were also taken before and after the pumps, as well, to diagnose any problems and verify and calibrate sensors. hilled Water and ot Water System Balance he MS Annex has chilled water and hot water pumps which are all equipped with a VFD and located in the mechanical room behind the bowling and games area. For the chilled water and hot water systems, the pumps operate in the same manner. he pump speeds are controlled by the VFDs to maintain the building loop DP setpoint. For both systems, pump # will come online when the VFD calls for a speed above 0%. When pump # reaches a speed of 95%, pump # will come online. When both pumps are running, both are operating at the same speed. When pump # speed falls below 50%, it will turn off. If pump # speed falls below %, it too will turn off. he DP setpoint for the chilled water is determined by the chilled water control valve on AU MB-. If the control valve is below 5% open, the DP setpoint is 0 psi. When the control valve is above 5% open, the DP setpoint is 0 psi. he building hot water system DP setpoint is a constant 0 psi, which is set by the operator. For the chilled water system, the DP setpoint operation is similar but reset. he minimum DP setpoint is 0 psi and the maximum is 5 psi. When the chilled water control valve on AU MB- is below 85% open, the DP setpoint will be 0psi. When this control valve is above 85% open, the DP setpoint is 5 psi. For the hot water system, the DP setpoint is reset based on the outside air dry bulb temperature as shown in table below. able : MS Annex hot water system DP setpoint reset schedule Outside emp. ( F) MS Main DP setpoint (psi) In September of 00, it was found that there was a hot water problem with the MS, Koldus, G. ollie White, and Kyle Academic Building. he hot water pump for the Kyle Academic Building was installed incorrectly and the pump s suction side was on the primary return line and the discharge was into the primary supply loop. his caused the hot water supply to the surrounding buildings to be at a lower temperature (0 F) than the desired supply temperature (0 F) and the buildings were cold. his problem was quickly corrected. Verification of Zone eheats All of the terminal reheats were checked for sound operation. his included checking reheat valves, reheat coils, and dampers. hese coils were washed on the air side and back flushed on the water side. Also, the valves were checked to determine if they are leaking by or not. erminal reheats were only found on MB-, MB-, MB-, and M-. roubleshooting he outside air damper for M- was installed backwards. 0

23 he space temperature sensor for AU M- was calibrated since it read 7 F when a temperature of 9. F was measured. his sensor modulates cooling and heating control valves to maintain the space temperature at its setpoint. oom was cold. he pneumatic control valves were checked to ensure proper operation and the thermostat was calibrated. he room temperature then increased form 8 F to 7 F. ecommendations Multiple chilled water control valves need to be replaced. All six zone reheat need to be repiped, and other mechanical problems need to be solved as well. See Appendix B for details. Energy onsumption Analysis ue to the parts the mechanical concerns found during commissioning were not corrected, such as control valve on AUS. Energy savings should be achieved when those bad control valves are replaced.

24 MS otel Introduction he MS Main is a three-story building was constructed in 950 as part of the MS Main building. It has a total of rooms and a total conditioned floor area of,900 square feet. he first floor of the MS otel is the reception area and the second and third floors are the hotel rooms. he VA system for this building consists of AUs and fan and coil units (FUs). One of the AUs serves the hallway between the rooms on the second floor and the other AU serves the hallway on the third floor. he FUs serve the individual rooms for the MS otel. Some of the larger rooms use more than one FU. he chilled and hot water to the MS otel is supplied by pumps for the MS Main. hese pumps were detailed in the MS Main section of this report. Building VA Systems he MS otel building consists of AUs, both of which are pneumatically controlled by local thermostats. hese thermostats control the cooling coils for AUs otel- and otel- to maintain the hallway s temperature setpoint. Figure 0 shows the schematic for these two AUs. he FUs for the hotel rooms are all pneumatically controlled by a local thermostat in the room. hese FUs have a cooling coil and then a heating coil and draw air in from the ceiling which is a common plenum for all of the FUs. A fresh air fan, which serves the two AUs also supplies fresh air to the plenum in the ceiling. All of the units also have a fan speed controller located on the wall near the thermostat. 5 o Space Energy Baseline and Metering Figure : AU otel- and otel- schematic he hotel shares the hot water and chilled water pumps with MS Main. For energy consumption see MS Main for details. Existing AU and FU onditions and Optimization he FUs located in each of the rooms were in fair working order. owever many of the heating or cooling valves or both were either stuck or leaking by on all of the FUs. Also, many of the thermostats were out of calibration and have been calibrated. he room temperature setpoint is controlled by a room thermostat and the setpoint is set by the user. he return air filters in most of the FUs were also very dirty. Appendix details the FU check list and malfunctioning parts. he fresh air fan which supplies outside air to the two AUs and the ceiling plenum was not running. his was checked and is now operating.

25 ommissioning Activities ommissioning activities included the measuring of all AUs for airflows and temperatures. Also, the chilled and hot water pressures and temperatures before and after the coils were measured for each AU. hese measurements were used to diagnose any problems with the air handlers. hese measurements were also used to verify and calibrate local sensors, if needed. Other mechanical inspections were conducted as well such as checking dampers, filters, fan belts, control valve operation, and fan operation. Also, cooling and heating coils in the units were cleaned and the waterside was back flushed. Local thermostats were also calibrated if needed and control valve spring ranges were verified and adjusted as needed. he FUs for each room were checked. his involved calibrating the thermostats and checking the cooling and heating control valves for proper function. Verification of erminal Box Operation All of the terminal boxes were checked for sound operation. his included checking reheat valves, reheat coils, and dampers. hilled Water and ot Water System Balance hilled water and hot water for the MS otel is supplied by the pumps from the MS Main. See the MS Main section for details on this system. he hot water and chilled water piping in the MS otel is rusted and in bad condition. ecommendations ) e-pipe the chilled water and hot water systems, which is list in Appendix B ) eplace existing three-way chilled water and hot water control valves on all FUs with new two-way control valves except the last FU on the rd floor, which is list in Appendix B.

26 Appendix A: AU s AU No. EXIS- Date ime oa Schematic of AU 5 o Zones FM emp.. Other hecks 5 0, % 9% 7.50% 9.0% *0 5* VFD (z) Belt n/a hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :here is not design information fir this unit.

27 Appendix A: AU s (continued) MS AU No. Date ime oa EXIS-, room 0 7-May Schematic of AU Michael and Jorge 5 o Zones FM emp.. % 5 5, hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : here is no design information for this unit. 5

28 Appendix A: AU s (continued) AU No. EXIS- Date ime oa Schematic of AU 5 o Zones FM emp.. Other hecks 5 0, % 5.70% 95% VFD (z) Belt n/a ok ok hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :

29 Appendix A: AU s (continued) AU No. Date ime oa -Mar chenggang/jorge Schematic of AU 5 7 o Space FM emp.. Other hecks 5 7,0,870, " VFD (z) Belt n/a hilled Water Side Ps(psi) 00 Pr (psi) 9 s (F). r(f) 55 ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : Bad W control valve, it does not move.he heating hot water valve is partially close. It moves when unplug air line but goes back to close position afterwards. No ports for hot water lines. 7

30 Appendix A: AU s (continued) AU No. Date ime oa Schematic of AU 5 7 o Space FM emp.. Other hecks 5 7 0,50, " x0 VFD (z) Belt n/a dirty Ps(psi) 8 Pr (psi) 80 hilled Water Side s (F) 5.5 r(f) 0 ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :he hot water return valve was closed. We opened it and went to the t-stat location (back office of bookstore) calibrate it and observed that the t-stat was controlling properly. What happen is that the customer has a computer monitor underneath the t-stat and are running an office heater so the unit is always calling for cooling. We explained to the customer that they have to remove the monitor and stop using the heater but it seems that they have not done so because the hot water is actually not running through. 8

31 Appendix A: AU s (continued) AU No. Date ime oa Schematic of AU 5 o Zones FM emp.. Other hecks ,0,975, " % * VFD (z) Belt n/a clean ok hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : 9

32 Appendix A: AU s (continued) AU No. Date ime oa /0/0 7 Michael Schematic of AU 5 o Space FM emp.. Other hecks 5,000, VFD (z) Belt 0 ok ok hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) 0

33 Appendix A: AU s (continued) AU No. 8 Date ime oa 9-Dec Schematic of AU 5 o Zones FM emp.. Other hecks 5 580, , " x x VFD (z) Belt n/a hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : s dirty; Belts loose; WV ; W coil is clean; e-heat coils were dirty. SP before re-heat coil = 0.88; SP after re-heat coil = 0.0.

34 Appendix A: AU s (continued) AU No. 8-Final measurement Date ime oa Schematic of AU 5 o Zones FM emp.. Other hecks 5 580,500, x VFD (z) Belt n/a hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : he condensing drain needs to be cleaned out.

35 Appendix A: AU s (continued) AU No. 9 Date ime oa Schematic of AU P 5 o Zones FM emp.. Other hecks 5 7,00 7,00, " VFD (z) Belt n/a hilled Water Side Ps(psi) 77 Pr (psi) 75 s (F) r(f) 0 ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :

36 Appendix A: AU s (continued) AU No. 0 Date ime oa Schematic of AU 5 o Zones FM emp.. Other hecks 5,800 5,700 0,700 5,00 5, " % 7% 00% VFD (z) Belt n/a hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :

37 Appendix A: AU s (continued) AU No. Date ime oa 5//0 Schematic of AU Jorge & Frank 5 o Zones FM emp.. Other hecks 5,880 9,70 8,000 8, " 0.9 8*8 VFD (z) Belt n/a ok loose hilled Water Side Ps(psi) Pr (psi) s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : 5

38 Appendix A: AU s (continued) AU No. Date ime oa 0/05/0 Jorge Schematic of AU 5 7 o Space FM emp.. Other hecks 5 7,50 0,75 9,00 0 x " VFD (z) Belt n/a Ps(psi) Pr (psi) 7 hilled Water Side s (F). r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :here are no W ports. here are no W S ports but the line is the same as for AU.

39 Appendix A: AU s (continued) AU No. Date ime oa 0/05/0 Jorge Schematic of AU 5 o Zones FM emp.. Other hecks 5 5,50,780 x " VFD (z) Belt n/a hilled Water Side Ps(psi) Pr (psi) s (F). r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note : coming into mechanical room ~500cfm. here is an opening in the wall of " x " that is letting probably too much return air to the return louvers. 7

40 Appendix A: AU s (continued) AU No. Date ime oa 0/05/0 Marvin and Frank Schematic of AU 5 7 o Space FM emp.. Other hecks ,50, " x 0.5 VFD (z) Belt n/a Ps(psi) Pr (psi) hilled Water Side s (F) r(f) ot Water Side Ps (psi) Pr (psi) s (F) r (F) Note :hilled water only has a return port but it is stuck. here are no W ports. eturn Air from umors =70.F, Duct size = x, cfm = 850 8