Technical Assignment 3 11/15/04. Executive Summary

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1 Executive Summary This report is an analysis of the existing systems within the Outreach Innovation Building in University Park, PA. One significant design criteria was a lower than average noise criteria within some spaces of the building such as the radio and television production rooms. The project is currently being constructed and therefore utility billing and energy consumption data is not available. General descriptions and system requirements are given for all air handlers, chilled water control sequence, and heating hot water control sequence. The critique of the system includes mechanical system costs (actual costs were not available, RS Means was used to estimate major equipment only), space requirements, maintainability, and environmental control and indoor air quality. Schedules and schematic diagrams were made using the design documents. Schematics include air handling diagrams, heating hot water diagram, and chilled water diagram. Schedules include all major equipment information. The analysis concluded that the existing systems are adequate in all areas analyzed.

2 Table of Contents Design Objectives and Requirements 1 Energy Sources and Rates 1 Site Factors 1 Design Conditions 2 System Requirements 3 Chilled Water Temperature Control System 4 Heating Hot Water Temperature Control Sequence 5 Operating History 5 Critique of System 6-7 AHU Diagram 1 8 AHU Diagram 2 9 Heating/Chilled Water Diagrams 10 Equipment Schedules 11-12

3 Design Objectives and Requirements The design requirements for the are that of a type B building in the International Building Code The mechanical systems must meet the heating/cooling loads and the ventilation requirements set by the International Building Code Noise Criteria was also considered due to the multiple television and radio studios throughout the building. An NC of 20 to 25 was designed for such spaces. Duct sizes were increased to reduce the velocity of the supply air and therefore lower the sound pressure level in order to comply with these design standards. Under-floor air distribution was used in open office areas. This enables a floor plan that can easily be changed. Also the large amounts of telecommunication cables can be placed within this raised floor area. Energy Sources and Rates The electricity rates for the were taken from a document about the West Penn Power Company: Rates, Terms, and Conditions Governing Interchange of Electricity with The Pennsylvania State University (Issued Dec 30, 2003). DEMAND CHARGE First 10,000 kilovolt-amperes Additional kilovolt-amperes ENERGY CHARGE All kilowatt-hours All kilowatt-hours $0.91 per kilovolt-ampere $0.90 per kilovolt-ampere $ per kilowatt-hour $ per kilowatt-hour (Effective ) Site Factors No major site factors influenced the design. The building is being built in a developing region on Penn State University land. 1

4 Design Conditions Outdoor design conditions Summer 89 F DB, 72 F MWB (0.4%) Winter 5 F DB (99.6%) Indoor design conditions 74 F and 50% relative humidity year round (Design conditions taken from ASHRAE Fundamentals 2001) Design Heating/Cooling Loads SYMBOL HEATING COOLING MBH MBH AHU-1A AHU-1B AHU-2A AHU-2B AHU-3A AHU-3B B B B CH CH CH

5 System Requirements AHU-1A, 1B, 2A, 2B General Description Air units are variable air volume units, comprised of the following: mixing box with separate minimum and modulating outdoor dampers, filter section, hot water heating coil, access section, chilled water cooling coil, humidifier, access section, and plenum supply fan. The system return fans are vane axial frequency drives. These units serve production areas on the First Floor. Freezestat shall de-energize the fans whenever the temperature falls below setpoint (36F, adj.). Smoke Detector: The unit shall shut down upon actuation of any smoke detector and initiation by the Fire Alarm System for air unit shutdown. Start Time Optimization: The Building Automation System (BAS) shall automatically calculate the optimum time to start the unit(s) based on space temperature, ambient temperature, and a building heat loss/gain coefficient in order to bring the space temperature to the proper setpoint no more than 15 minutes before scheduled occupancy time. Static Pressure High Limit Sensor: System shall turn off upon actuation of duct static pressure high limit sensor. Fan Tracking: Supply fan air volume shall be controlled with variable frequency drive via static pressure sensors in the supply air ductwork, setpoint 0.75 in/wg, adj. Return fan shall be modulated with variable frequency drive to maintain a fixed CFM differential between supply and return as measured by air measuring devices, equal to minimum outside air and/or building exhaust, plus building pressurization CFM. AHU-3A and 3B These units supply the under-floor air distribution system. General Description similar to AHU-1A, 1B, 2A, 2B above. 3

6 Chilled Water Temperature Control Sequence General Description The chilled water system is primary-secondary plant, comprised of the following components: air-cooled chillers with evaporator barrel remotely located in mechanical Penthouse, primary chilled water pumps (constant speed) dedicated to each evaporator barrel, and variable speed secondary chilled water pumps that deliver chilled water to terminal cooling coils. To prevent short cycling, each chiller shall run for a minimum of 30 minutes and be off a minimum of 20 minutes. On failure of the lead pump, the lag pump will run and the lead pump will be de-energized. The chiller will shut down and an alarm set off if a refrigerant leak is detected within the mechanical penthouse. The chiller plant shall be enabled to run whenever ambient temperature is greater than 50F. Secondary chilled water pump(s) will be energized any time the chiller(s) is called to run. Pump speed will be modulated to maintain differential pressure sensor setpoint of 25 ft/wg. 4

7 Heating Hot Water Temperature Control Sequence General Description The heating hot water system is primary-secondary plant, comprised of the following components: gas-fired hot water boilers, primary hot water pumps (constant speed) dedicated to each boiler, and variable speed secondary hot water pumps that deliver heating hot water to terminal heating units (coils, finned tube radiation, radiant ceiling panels, and cabinet unit heaters). To prevent short cycling of the boilers, each boiler shall run for a minimum of 5 minutes and be off a minimum of 1 minute. The boiler plant will run whenever ambient temperature is less than 65 F. Secondary hot water pump(s) will be energized any time the boiler(s) is called to run. Pump speed will be modulated to maintain differential pressure sensor setpoint of 15 ft/wg. Operating History The operating history for the is not available. (Building not complete as of November 15, 2004) 5

8 Critique of System Mechanical System Cost Actual mechanical system costs were not able to be obtained. Only major mechanical equipment such as air-handling units, chillers, boilers, etc. was taken into account. No piping, ductwork, under-floor air distribution system (including grilles), or labor were taken into consideration for this assignment. Actual bidding documents could not be obtained, therefore RS Means Facilities Construction Cost Data, 17 th Annual Edition was used to estimate the major mechanical equipment cost. Due to the omission of parts of the mechanical system the cost estimation is low compared to the actual value. The following chart is a breakdown of equipment estimated. RS MEANS 2002 Cost Estimation CHILLER SIZE TYPE QUANTITY UNIT PRICE TOTAL COST CH KW AIR CH KW AIR CH KW AIR AIR HANDLING SIZE TYPE QUANTITY UNIT PRICE TOTAL COST AHU-1A&B 10,000 CFM HORIZ. DRAW AHU-2A&B 17,500 CFM HORIZ. DRAW AHU-3A&B 35,000 CFM HORIZ. DRAW HUMIDIFIERS SIZE TYPE QUANTITY UNIT PRICE TOTAL COST H LBS/HR H LBS/HR H LBS/HR FAN SIZE TYPE QUANTITY UNIT PRICE TOTAL COST EF CFM EF CFM EF CFM EF CFM CSF CFM PUMP SIZE TYPE QUANTITY UNIT PRICE TOTAL COST P-1A&B 80 GPM INLINE P-2&3 280 GPM END SUCT P-4A&B 640 GPM END SUCT P-5,6,7 130 GPM INLINE P-8A&B 320 GPM END SUCT BOILER SIZE TYPE QUANTITY UNIT PRICE TOTAL COST B MBH TOTAL EQUIP. COST EQUIP. COST PER FT^

9 Space Requirements Floor area for the mechanical equipment including shaft area totals approximately 7,400 sq.ft. This does not include the exterior penthouse space which is approximately 1600 sq.ft. These areas appear to be adequate for the mechanical systems and do not seem to pose any problems such as duct or pipe layout, etc. Maintainability Serviceability of equipment does not appear to be an issue. All major equipment appears to have adequate clearance in order for maintenance and/or replacement of parts. Under-floor air distribution system allows for flexibility of spaces and access to under-floor VAV boxes and equipment. All ceilings allow for access to piping and ductwork where necessary. Environmental Control and Indoor Air Quality The ASHRAE Standard analysis showed that ventilation rates meet the minimum requirements and IAQ is not an issue. Equipment selected is also able to meet the required load, and therefore environmental control is also not an issue. 7

10 AHU 1A & 1B DIAGRAM (AHU-2A &2B SIMILAR, EXCEPT AS NOTED) COMPONENT LEGEND 1. MIXING BOX 2. PRE- AND FINAL FILTERS 3. HEATING COIL 4. ACCESS SECTION 5. COOLING COIL/ COND. DRAIN PAN 6. HUMIDIFIER 7. ACCESS SECTION 8. SUPPLY FAN (PLENUM TYPE) 9. RETURN FAN (VANE AXIAL TYPE) NOTES 1. MIXED AIR TEMPERATURE SETPOINT - AHU-1A/B = 49.5 F - AHU-2A/B = 51.5 F 2. DISCHARGE TEMPERATURE SETPOINT - AHU-1A/B = 50.5 F - AHU-2A/B = 52.5 F 3. STATIC PRESSURE SENSORS - AHU-1A/B = QTY.1 - AHU-2A/B = QTY.2 8

11 AHU 3A & 3B DIAGRAM (UNDERFLOOR AIR SYSTEM) COMPONENT LEGEND 1. MIXING BOX 2. PRE- AND FINAL FILTERS 3. HEATING COIL 4. ACCESS SECTION 5. COOLING COIL/ COND. DRAIN PAN 6. RETURN AIR BYPASS SECTION W/ FILTER AND CNTRL. DAMP. 7. HUMIDIFIER 8. ACCESS SECTION 9. SUPPLY FAN (PLENUM TYPE) 10. RETURN FAN (VANE AXIAL TYPE) 9

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13 CHILLER SCHEDULE SYMBOL CAPACITY EVAPORATOR CONDENSER COMPRESSOR GENERAL REFRIGERANT (TON) GPM EWT(F) LWT(F) AMB. (F) QTY. FANS TOT. FAN KW TOTAL KW TOT. CH. KW V-Ph-Hz CH-1 54 HCFC CH HCFC CH HCFC BOILER SCHEDULE SYMBOL CAPACITY (MBH) BURNER (GAS) PRESSURE (IN/WG) DESIGN PRESSURE ELECTRICAL DATA INPUT OUTPUT MIN. MAX. (PSIG) AMPS V-Ph-Hz B B B AIR TERMINAL SCHEDULE AIR SEPARATOR SCHEDULE EXPANSION TANK SCHEDULE SYMBOL MIN CFM MAX CFM TYPE MAX SP. (IN/WG) SYMBOL SERVICE SYMBOL SERVICE TYPE AD AS-1 HW SYSTEM ET-1 HW SYS. VERTICAL AD AS-2 CW SYSTEM ET-2 CHW SYS. VERTICAL AD P-4A (4B) SECOND CHW AD AD AD AD AD AD CFM/LF - LINEAR 0.02 AD CFM/LF - LINEAR 0.05 AD AD ROUND CONE RG/EG EGGCRATE 0.05 RG/EG EGGCRATE 0.05 RG/EG EGGCRATE 0.05 RG/EG EGGCRATE 0.02 RG/EG BAR GRILLE 0.05 RG/EG BAR GRILLE 0.05 RG/EG BAR GRILLE 0.05 RG/EG BAR GRILLE 0.05 AIR HANDLING UNIT SCHEDULE (CONTINUED BELOW) SYMBOL TYPE SUPPLY FAN RETURN FAN COOLING COIL TOTAL CFM TSP (IN/WG) MIN OA CFM MOTOR HP TOTAL CFM TSP (IN/WG) MOTOR HP TOT TONS CFM EAT (DB/WB) LAT (DB/WB) FACE VEL. (FPM) EWT (F) LWT (F) GPM AHU-1A VAV HOR DRAW / / AHU-1B VAV HOR DRAW / / AHU-2A VAV HOR DRAW / / AHU-2B VAV HOR DRAW / / AHU-3A VAV HOR DRAW / / AHU-3B VAV HOR DRAW / / AIR HANDLING UNIT SCHEDULE (CONTINUED) SYMBOL PREHEAT COIL HUMIDIFIER TOTAL MBH CFM EAT (DB/WB) LAT (DB/WB) FACE VEL (FPM) EWT (F) LWT (F) GPM STEAM LB/HR STM PRES. (PSI) AHU-1A AHU-1B AHU-2A AHU-2B AHU-3A AHU-3B

14 FAN-POWERED TERMINAL BOX SCHEDULE - SERIES FLOW (FPB) SYMBOL PRIMARY AIR (COOLING) FAN DATA (HEATING) HEATING COIL HOT (HOT WATER) MAX CFM MIN CFM SP (IN/WG) SP (IN/WG) HP CFM MBH SP GPM EWT FPB FPB FPB FPB FPB FPB FPB FPB FAN COIL UNIT SCHEDULE SYMBOL FAN DATA HEATING COIL (HOT WATER) TOTAL CFM MIN OA CFM MOTOR HP&W V-Ph-Hz CFM CAPACITY (MBH) EAT (DB) LAT(DB) GPM EWT (F) FCU /16 95W FCU /8 95W FCU /8 125W FCU /8 125W FAN SCHEDULE SYMBOL CFM SP W.C. HP OR WATTS RPM TIP SPEED V-Ph-Hz EF /2 HP EF /3 HP EF HP EF W CSF W VARIABLE VOLUME BOX SCHEDULE (V V) SYMBOL INLET MAX DESIGN MIN. SP HEATING COIL (HOT WATER) (4) DIA (IN) CFM (1) CFM (2) (IN/WG) (3) CFM MBH (5) EAT (F) SP (IN/WG) (6) GPM (7) EWT (F) WPD (FT/WG) V V V V V V V V V V V V V V V V HUMIDIFIERS SYMBOL SERVICE TOTAL OUTDOOR AIR HUMIDITY ROOM TEMP MAX STEAM MAX INPUT GAS INLET ELECTRICAL CFM % (F) FLOW (LBS/HR) (MBH) PRES. (INWC) H-1 AHU 1A&1B FLA H-2 AHU 2A&2B FLA H-3 AHU 3A&3B PUMP SCHEDULE SYMBOL SERVICE TYPE PUMP MOTOR GPM HEAD (FT/WG) MHP RPM V-Ph-Hz P-1A (P-1B) PRIM CHW (CH-1) INLINE P-2 (P-3) PRIM CHW (CH-2&3) END SUCT P-4A (P-4B) SECOND CHW END SUCT P-5 (P-6&7) PRIM HW (B-1,2,3) INLINE P-8A (P-8B) SECOND HW END SUCT UNIT HEATER SCHEDULE SYMBOL TYPE HEATING COIL (HOT WATER) MBH GPM EAT (F) EWT (F) WPD (FT/WG) FAN CFM FAN HP V-Ph-Hz UH-1 HORIZ / UH-2 HORIZ /