PLANT HVAC SYSTEMS DU-109-PP PLANT HVAC SYSTEMS

PURPOSE OBJECTIVES PURPOSE OBJECTIVES PLANT HVAC SYSTEMS PURPOSE The purpose of the Operations and Maintenance Training Program is to train Operations and Maintenance Technicians in the operation of the Duke University Plant Heating, Ventilation, and Air Conditioning (HVAC) Systems. OBJECTIVES Trainees will demonstrate knowledge of HVAC System Components HVAC System Components Operation HVAC System Configuration HVAC System Controls and Instrumentation PURPOSE The purpose of the Operations and Maintenance Training Program is to train Operations and Maintenance Technicians in the operation of the Duke University Plant Heating, Ventilation, and Air Conditioning (HVAC) Systems. OBJECTIVES Trainees will demonstrate knowledge of HVAC System Components HVAC System Components Operation HVAC System Configuration HVAC System Controls and Instrumentation

PLANT HVAC SYSTEMS PURPOSE The purpose of the Heating, Ventilation, and Air Conditioning (HVAC) System is to: Provide heat and cooling climate control for plant, office/control room, and electrical room areas of the steam and chiller plants Maintain Interior Air Quality (IAQ) Maintain air pressure Provide emergency exhaust PURPOSE The purpose of the Heating, Ventilation, and Air Conditioning (HVAC) System is to: Provide heat and cooling climate control for plant, office/control room, and electrical room areas of the steam and chiller plants Maintain Interior Air Quality (IAQ) Maintain air pressure Provide emergency exhaust

HVAC AIR FUNCTIONS Return Air Outside Air Supply Air PLANT HVAC SYSTEMS HVAC AIR FUNCTIONS To understand how HVAC works, you need to be familiar with the six functions of HVAC air. Return Air Air inside the building drawn back into the air handlers Outside Air Fresh air drawn into the air handlers from outside Supply Air Air blown into the building from the air handlers HVAC AIR FUNCTIONS To understand how HVAC works, you need to be familiar with the six functions of HVAC air. Return Air Air inside the building drawn back into the air handlers Outside Air Fresh air drawn into the air handlers from outside Supply Air Air blown into the building from the air handlers

Relief Air Relief Air HVAC AIR FUNCTIONS Makeup Air Exhaust Air PLANT HVAC SYSTEMS HVAC AIR FUNCTIONS Makeup Air Air blown into the building by Makeup Air Unites (MAUs) to maintain air pressure balance when pressure is low Relief Air Air exhausted from the building to maintain air pressure balance when air pressure is high Exhaust Air Air expelled to remove contaminants from areas where chemicals, hazardous materials, and toxic gases are present Air exhausted from the building in case of emergency HVAC AIR FUNCTIONS Makeup Air Air blown into the building by Makeup Air Unites (MAUs) to maintain air pressure balance when pressure is low Relief Air Air exhausted from the building to maintain air pressure balance when air pressure is high Exhaust Air Air expelled to remove contaminants from areas where chemicals, hazardous materials, and toxic gases are present Air exhausted from the building in case of emergency

WHY AIR BALANCE IS IMPORTANT PLANT HVAC SYSTEMS WHY AIR BALANCE IS IMPORTANT Over Pressure and Under Pressure conditions negatively affect building efficiency. Over Pressure When air pressure inside a building is higher than pressure outside, the conditioned air inside the building is pushed outside. High air pressure can require excess energy to condition the air in the building and compensate for energy lost. WHY AIR BALANCE IS IMPORTANT Over Pressure and Under Pressure conditions negatively affect building efficiency. Over Pressure When air pressure inside a building is higher than pressure outside, the conditioned air inside the building is pushed outside. High air pressure can require excess energy to condition the air in the building and compensate for energy lost.

WHY IS AIR BALANCE IMPORTANT? Under Pressure PLANT HVAC SYSTEMS WHY IS AIR BALANCE IMPORTANT? Under Pressure When building pressure is lower than pressure outside, the air outside is drawn inside. Outside air may come from undesirable sources (trash bins, open doors, cracks, construction, and so forth). Unfiltered or unconditioned air can affect the HVAC system’s ability to maintain the desired environment. WHY IS AIR BALANCE IMPORTANT? Under Pressure When building pressure is lower than pressure outside, the air outside is drawn inside. Outside air may come from undesirable sources (trash bins, open doors, cracks, construction, and so forth). Unfiltered or unconditioned air can affect the HVAC system’s ability to maintain the desired environment.

QUESTION What does IAQ stand for? QUESTION What does IAQ stand for? PLANT HVAC SYSTEMS QUESTION What does IAQ stand for? International Air Quality Industrial Air Quality Interior Air Quality In-duct Air Quality QUESTION What does IAQ stand for? International Air Quality Industrial Air Quality Interior Air Quality In-duct Air Quality

IAQ stands for Interior Air Quality. PLANT HVAC SYSTEMS ANSWER IAQ stands for Interior Air Quality. ANSWER IAQ stands for Interior Air Quality.

What kind of air is blown into building from air handlers? PLANT HVAC SYSTEMS QUESTION What kind of air is blown into building from air handlers? Return Air Outside Air Makeup Air Supply Air QUESTION What kind of air is blown into building from air handlers? Return Air Outside Air Makeup Air Supply Air

Supply Air is recirculated through the air handlers. PLANT HVAC SYSTEMS ANSWER Supply Air is recirculated through the air handlers. ANSWER Supply Air recirculates through the air handlers.

What kind of air is added when air pressure is low? PLANT HVAC SYSTEMS QUESTION What kind of air is added when air pressure is low? Return Air Outside Air Makeup Air Supply Air QUESTION What kind of air is blown into a building from air handlers? Return Air Outside Air Makeup Air Supply Air

Makeup Air is blown into a building when air pressure is low. PLANT HVAC SYSTEMS ANSWER Makeup Air is blown into a building when air pressure is low. ANSWER Makeup Air is blown into a building when air pressure is low.

What causes Over Pressure? PLANT HVAC SYSTEMS QUESTION What causes Over Pressure? Pressure is higher on the lower level than on the mezzanine Pressure is lower in the building than outside Pressure is higher in the building than outside Pressure is lower on the lower level than on the mezzanine QUESTION What causes Over Pressure? Pressure is higher on the lower level than on the mezzanine Pressure is lower in the building than outside Pressure is higher in the building than outside Pressure is lower on the lower level than on the mezzanine

PLANT HVAC SYSTEMS ANSWER Over Pressure is the condition when pressure inside the building is higher than outside. ANSWER Over Pressure is the condition when pressure inside the building is higher than outside.

What causes Under Pressure? PLANT HVAC SYSTEMS QUESTION What causes Under Pressure? Pressure is higher on the lower level than on the mezzanine Pressure is lower in the building than outside Pressure is higher in the building than outside Pressure is lower on the lower level than on the mezzanine QUESTION What causes Under Pressure? Pressure is higher on the lower level than on the mezzanine Pressure is lower in the building than outside Pressure is higher in the building than outside Pressure is lower on the lower level than on the mezzanine

PLANT HVAC SYSTEMS ANSWER Under Pressure is the condition when pressure inside the building is lower than outside. ANSWER Under Pressure is the condition when pressure inside the building is lower than outside.

PLANT HVAC COMPONENTS PLANT HVAC COMPONENTS Air Handler Units (AHUs) PLANT HVAC SYSTEMS PLANT HVAC COMPONENTS Air Handler Units (AHUs) Makeup Air Units (MAUs) Fan Coil Units (FCUs) Exhaust fans Supply fans Emergency exhaust fans PLANT HVAC COMPONENTS Air Handler Units (AHUs) Makeup Air Units (MAUs) Fan Coil Units (FCUs) Exhaust fans Supply fans Emergency exhaust fans

The Mixing Box section contains: PLANT HVAC SYSTEMS AHU COMPONENTS The Mixing Box section contains: Return Air Damper which connects to the Return Air Duct The Relief Air Damper also connects to the Return Air Duct Outside Air Damper which connects to the duct to the building exterior RETURN AIR DAMPER OUTSIDE AIR RELIEF AIR MIXING BOX AHU COMPONENTS The Mixing Box section contains: Return Air Damper which connects to the Return Air Duct The Relief Air Damper also connects to the Return Air Duct Outside Air Damper which connects to the duct to the building exterior

The Filter section contains: PLANT HVAC SYSTEMS AHU COMPONENTS The Filter section contains: Access door for filter element replacement W.C. Meter mounted in door Filter is replaced when air pressure reaches maximum resistance RETURN AIR W.C. METER RELIEF AIR MIXING BOX AHU COMPONENTS The Filter section contains: Access door for filter element replacement W.C. Meter mounted in door Filter is replaced when air pressure reaches maximum resistance OUTSIDE AIR FILTER

The Cooling Coil section contains: PLANT HVAC SYSTEMS AHU COMPONENTS The Cooling Coil section contains: In and Out connections for chilled water Cooling coil heat exchanger RELIEF AIR MIXING BOX RETURN AIR AHU COMPONENTS The Cooling Coil section contains: In and Out connections for chilled water Cooling coil heat exchanger OUTSIDE AIR COOLING COIL FILTER

The Heating Coil section contains: PLANT HVAC SYSTEMS AHU COMPONENTS The Heating Coil section contains: In and Out connections for steam Heating coil heat exchanger RETURN AIR RELIEF AIR MIXING BOX COOLING COIL AHU COMPONENTS The Heating Coil section contains: In and Out connections for steam Heating coil heat exchanger OUTSIDE AIR HEATING COIL FILTER

The Fan section contains: PLANT HVAC SYSTEMS AHU COMPONENTS The Fan section contains: Fan and motor Starter Box mounted on exterior or nearby RETURN AIR AHU COMPONENTS The Fan section contains: Fan and motor Starter box mounted on exterior or nearby OUTSIDE AIR HEATING COIL COOLING COIL FILTER MIXING BOX

What is accomplished in the AHU mixing box? PLANT HVAC SYSTEMS QUESTION What is accomplished in the AHU mixing box? Return air is mixed with relief air Supply air is mixed with return air Supply air is mixed with outside air Return air is mixed with outside air QUESTION What is accomplished in the AHU mixing box? Return air is mixed with relief air Supply air is mixed with return air Supply air is mixed with outside air Return air is mixed with outside air

Return air is mixed with outside air in the AHU mixing box. PLANT HVAC SYSTEMS ANSWER Return air is mixed with outside air in the AHU mixing box. ANSWER Return air is mixed with outside air in the AHU mixing box.

What kind of meter is mounted in the filter section door of an AHU? PLANT HVAC SYSTEMS QUESTION What kind of meter is mounted in the filter section door of an AHU? Temperature sensor Pressure gauge W.C. meter Anemometer QUESTION What kind of meter is mounted in the filter section door of an AHU? Temperature sensor Pressure gauge W.C. meter Anemometer

PLANT HVAC SYSTEMS ANSWER A W.C. meter is mounted in the door of the filter section. The W.C. (Water Column) meter measures resistance through the filter in inches to indicate when the filter needs to be changed. ANSWER A W.C. meter is mounted in the door of the filter section. The W.C. (Water Column) meter measures resistance through the filter in inches to indicate when the filter needs to be changed.

Where is the starter box located for an AHU? PLANT HVAC SYSTEMS QUESTION Where is the starter box located for an AHU? Exterior of the fan section or nearby Mixing box Control Room AHUs do not need starters QUESTION Where is the starter box located for an AHU? Exterior of the fan section or nearby Mixing box Control Room AHUs do not need starters

The starter box is mounted on the fan section of the AHU or nearby. PLANT HVAC SYSTEMS ANSWER The starter box is mounted on the fan section of the AHU or nearby. ANSWER The starter box is mounted on the fan section of the AHU or nearby.

The Fan section contains: PLANT HVAC SYSTEMS MAU COMPONENTS The Fan section contains: Fan and motor Outside Air Damper which connects to the duct to the building exterior OUTSIDE AIR DAMPER FAN MAU COMPONENTS The Fan section contains: Fan and motor Outside Air Damper which connects to the duct to the building exterior

The Coil section contains: PLANT HVAC SYSTEMS MAU COMPONENTS The Coil section contains: In and Out connections for steam and chilled water Heating and cooling coil heat exchangers COOLING COIL HEATING OUTSIDE AIR DAMPER FAN MAU COMPONENTS The Coil section contains: In and Out connections for steam and chilled water Heating and cooling coil heat exchangers

The Filter section contains: PLANT HVAC SYSTEMS MAU COMPONENTS The Filter section contains: Filters Supply Air Damper COOLING COIL HEATING OUTSIDE AIR DAMPER FAN FILTER SUPPLY AIR MAU COMPONENTS The Filter section contains: Filters Supply Air Damper

The Starter box is located next to the MAU. PLANT HVAC SYSTEMS MAU COMPONENTS The Starter box is located next to the MAU. MAU COMPONENTS The Starter box is located next to the MAU.

What is one way an MAU differs from an AHU? PLANT HVAC SYSTEMS QUESTION What is one way an MAU differs from an AHU? The MAU takes in return air and outside air The MAU takes in relief air only The MAU takes in outside air only The MAU takes in return air only QUESTION What is one way an MAU differs from an AHU? The MAU takes in return air and outside air The MAU takes in relief air only The MAU takes in outside air only The MAU takes in return air only

The MAU takes in outside air only. PLANT HVAC SYSTEMS ANSWER The MAU takes in outside air only. ANSWER The MAU takes in outside air only.

QUESTION What does MAU stand for? QUESTION What does MAU stand for? PLANT HVAC SYSTEMS QUESTION What does MAU stand for? Main Air Unit Maximum Air Unit Mini Air Unit Makeup Air Unit QUESTION What does MAU stand for? Main Air Unit Maximum Air Unit Mini Air Unit Makeup Air Unit

MAU stands for Makeup Air Unit. PLANT HVAC SYSTEMS ANSWER MAU stands for Makeup Air Unit. ANSWER MAU stands for Makeup Air Unit.

What is another way an MAU differs from an AHU? PLANT HVAC SYSTEMS QUESTION What is another way an MAU differs from an AHU? The MAU has a mixing box The MAU does not have a mixing box The MAU has a cooling coil The AHU has a cooling coil QUESTION What is another way an MAU differs from an AHU? The MAU has a mixing box The MAU does not have a mixing box The MAU has a cooling coil The AHU has a cooling coil

The MAU does not have a mixing box. PLANT HVAC SYSTEMS ANSWER The MAU does not have a mixing box. ANSWER The MAU does not have a mixing box.

FCU COMPONENTS Outside Air Damper Electric Duct Heater FCU COMPONENTS PLANT HVAC SYSTEMS FCU COMPONENTS Outside Air Damper Electric Duct Heater RETURN AIR SUPPLY AIR ELECTRIC DUCT HEATER FCU COMPONENTS Outside Air Damper Electric Duct Heater OUTSIDE AIR DAMPER

FCU COMPONENTS Filter Cooling Coil Fan and Motor FCU COMPONENTS Filter PLANT HVAC SYSTEMS FCU COMPONENTS Filter Cooling Coil Fan and Motor FAN FCU COMPONENTS Filter Cooling Coil Fan and Motor COOLING COIL FILTER

What does the FCU use to heat supply air? PLANT HVAC SYSTEMS QUESTION What does the FCU use to heat supply air? Steam Hot water Electricity Friction QUESTION What does the FCU use to heat supply air? Steam Hot water Electricity Friction

PLANT HVAC SYSTEMS ANSWER The FCU uses an Electric Duct Heater to heat air in the supply air duct. ANSWER The FCU uses an Electric Duct Heater to heat air in the supply air duct.

QUESTION What does FCU stand for? QUESTION What does FCU stand for? PLANT HVAC SYSTEMS QUESTION What does FCU stand for? Forced Cooling Unit Facilities Control Unit Furnace Coil Unit Fan Coil Unit QUESTION What does FCU stand for? Forced Cooling Unit Facilities Control Unit Furnace Coil Unit Fan Coil Unit

FCU stands for Fan Coil Unit. PLANT HVAC SYSTEMS ANSWER FCU stands for Fan Coil Unit. ANSWER FCU stands for Fan Coil Unit.

PLANT HVAC SYSTEMS CONFIGURATION AND PROCESS FLOW The flow for Chiller Plant #2 is used as an example. PLANT HVAC SYSTEMS CONFIGURATION AND PROCESS FLOW The flow for Chiller Plant #2 is used as an example.

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Temperature Transmitters on the Return Air Duct, Supply Air Duct, and Mixing Box of AHU-21 send readings to the Local Controller Digital Control System (DCS). LOCAL CONTROLLER DCS RETURN AIR DUCT SUPPLY AIR DUCT MIXING BOX CHILLER PLANT #2 AHU-21 SYSTEM Temperature Transmitters on the Return Air Duct, Supply Air Duct, and Mixing Box of AHU-21 send readings to the Local Controller Digital Control System (DCS). AHU-21

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM The local DCS controls heating and cooling by modulating the Cooling Coil chilled water control valve and the steam valve supplying the Heating Coil. LOCAL CONTROLLER DCS COOLING COIL HEATING COIL CHILLER PLANT #2 AHU-21 SYSTEM The local DCS controls heating and cooling by modulating the Cooling Coil chilled water valve and the steam valve supplying the Heating Coil. MIXING BOX CHILLED WATER CONTROL VALVE STEAM VALVE

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM The Outside Air Damper is set at 2,000 CFM. The Return Air Damper is set at 30,000 CFM. SUPPLY AIR DAMPER D-21E CHILLER PLANT #2 AHU-21 SYSTEM The Outside Air Damper is set at 2,000 CFM. The Return Air Damper is set at 30,000 CFM. AHU-21 MIXING BOX OUTSIDE AIR DAMPER D-21F

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM 1,000 CFM exhausted continuously from Chemical Treatment area by Exhaust Fan EF-23. 350 CFM exhausted continuously from the Break Room, Men’s and Women’s Restrooms, Shower, and Janitor’s Closet by Exhaust Fan EF-24. BREAK ROOM WOMEN’S RESTROOM MEN’S RESTROOM JANITOR’S CLOSET SHOWER EXHAUST FAN EF-24 EXHAUST TO OUTSIDE CHILLER PLANT #2 AHU-21 SYSTEM 1,000 CFM exhausted continuously from Chemical Treatment area by Exhaust Fan EF-23. 350 CFM exhausted continuously from the Break Room, Men’s and Women’s Restrooms, Shower, and Janitor’s Closet by Exhaust Fan EF-24. LOUVER L-28

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Supply Fans SF-21 and SF-22 run continuously to recirculate air within the plant. AHU-21 SUPPLY FAN SF-21 SUPPLY FAN SF-22 CHILLER PLANT #2 AHU-21 SYSTEM Supply Fans SF-21 and SF-22 run continuously to recirculate air within the plant. EF-24

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation Based on outside air enthalpy and outside air temperature, when less than 60°F AHU-21 operates in economizer cycle modulating the outside and return air dampers to maintain 60°F supply air temperature. LOCAL CONTROLLER DCS CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation When outside air enthalpy and outside air temperature when less than 60°F, AHU-21 operates in economizer cycle modulating the outside and return air dampers to maintain 60°F supply air temperature. RETURN AIR DAMPER OUTSIDE AIR DAMPER

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation The chilled water valve to AHU-21 is closed during economizer cycle. In the event of damper failure or mixed air temperature below 35°F, a freezestat shuts down AHU-21 and sends an alarm. LOCAL CONTROLLER DCS FREEZESTAT CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation The chilled water valve to AHU-21 is closed during economizer cycle. In the event of damper failure or mixed air temperature below 35°F, a freezestat shuts down AHU-21 and sends an alarm. CHILLED WATER VALVE

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation Relief Air Damper RD-21 is controlled by differential pressure to maintain a 0.05 inch W.C. positive pressure in the building by modulating the damper. AHU-21 PRESSURE SENSOR A7 AT 0.05” W.C. RELIEF DAMPER RD-21 CHILLER PLANT #2 AHU-21 SYSTEM Economizer Operation Relief Air Damper RD-21 is controlled by differential pressure to maintain a 0.05 inch W.C. positive pressure in the building by modulating the damper.

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust During emergency when refrigerant accumulates above 100 PPM due to leak or rupture, air recirculation dampers to Exhaust Fans EF-21 and EF-22 close and exhaust dampers open forcing the refrigerant from the building. EMERGENCY EXHAUST DAMPER L-26 EMERGENCY EXHAUST DAMPER L-25 CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust During emergency when refrigerant accumulates above 100 PPM due to leak or rupture, air recirculation dampers to Exhaust Fans EF-21 and EF-22 close and exhaust dampers open forcing the refrigerant from the building. SOUTH EMERGENCY EXHAUST EF-22 NORTH EMERGENCY EXHAUST EF-21

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust Supply Fans SF-21 and SF-22 shut down. The outside air damper to AHU-21 opens fully and the return air damper closes. Additional outside air (30,000 CFM) brought into the building from AHU-21 is exhausted through Positive Relief Damper RD-1. When the refrigerant detectors no longer sense a low refrigeration concentration of 100 PPM, exhaust air dampers to EF-21 and 22 close and the air recirculation dampers open. SF-21 and 22 then energize and AHU-21 returns to a modulating damper cycle. CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust Supply Fans SF-21 and SF-22 shut down. The outside air damper to AHU-21 opens fully and the return air damper closes. Additional outside air (30,000 CFM) brought into the building from AHU-21 is exhausted through Positive Relief Damper RD-1. When the refrigerant detectors no longer sense a low refrigeration concentration of 100 PPM, exhaust air dampers to EF-21 and 22 close and the air recirculation dampers open. SF-21 and 22 then energize and AHU-21 returns to a modulating damper cycle.

CHILLER PLANT #2 AHU-21 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust If an emergency occurs when the supply air temperature is less than 60°F, a temperature sensor opens steam valve TCV-AHU-21B to maintain a supply air temperature of 60°F. CHILLER PLANT #2 AHU-21 SYSTEM Emergency Exhaust If an emergency occurs when the supply air temperature is less than 60°F, a temperature sensor opens steam valve TCV-AHU-21B to maintain a supply air temperature of 60°F.

PLANT HVAC SYSTEMS QUESTION Based on outside air enthalpy and outside air temperature, what is the lowest temperature at which AHU-21 will operate before entering the economizer cycle? 80°F 40°F 60°F 72°F QUESTION Based on outside air enthalpy and outside air temperature, what is the lowest temperature at which AHU-21 will operate before entering the economizer cycle? 80°F 40°F 60°F 72°F

PLANT HVAC SYSTEMS ANSWER Based on outside air enthalpy and outside air temperature, when less than 60°F AHU-21 operates in economizer cycle. ANSWER Based on outside air enthalpy and outside air temperature, when less than 60°F AHU-21 operates in economizer cycle.

When do Supply Fans SF-21 and SF-22 run? PLANT HVAC SYSTEMS QUESTION When do Supply Fans SF-21 and SF-22 run? Only when building pressure is low Continuously Only when building pressure is high Only at night QUESTION When do Supply Fans SF-21 and SF-22 run? Only when building pressure is low Continuously Only when building pressure is high Only at night

PLANT HVAC SYSTEMS ANSWER Supply Fans SF-21 and SF-22 run continuously to recirculate air within the plant. ANSWER Supply Fans SF-21 and SF-22 run continuously to recirculate air within the plant.

PLANT HVAC SYSTEMS QUESTION Where do the temperature transmitters on the ducts and mixing box on AHU-21 send readings? Local Controller DCS AHU-22 Directly to the Control Room Chiller Plant #1 QUESTION Where do the temperature transmitters on the ducts and mixing box on AHU-21 send readings? Local Controller DCS AHU-22 Directly to the Control Room Chiller Plant #1

PLANT HVAC SYSTEMS ANSWER Temperature Transmitters on the Return Air Duct, Supply Air Duct, and Mixing Box of AHU-21 send readings to the Local Controller Digital Control System (DCS). ANSWER Temperature Transmitters on the Return Air Duct, Supply Air Duct, and Mixing Box of AHU-1 send readings to the Local Controller Digital Control System (DCS).

COOLING COIL CHILLED WATER VALVE TCV-AHU-22A PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-22 SYSTEM AHU-22 supplies 10,000 CFM of cooling to the Electric Room. The local DCS modulates the cooling coil chilled water valve in response to temperature sensors in the supply and return air ducts and mixing box. LOCAL CONTROLLER DCS COOLING COIL CHILLER PLANT #2 AHU-22 SYSTEM AHU-22 supplies 10,000 CFM of cooling to the Electric Room. The local DCS modulates the cooling coil chilled water valve in response to temperature sensors in the supply and return air ducts and mixing box. COOLING COIL CHILLED WATER VALVE TCV-AHU-22A

CHILLER PLANT #2 AHU-22 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-22 SYSTEM The Outside Air Damper is set at 9,940 CFM. 60 CFM is exhausted continuously through the Gravity Relief Damper in the mezzanine floor. OUTSIDE AIR DAMPER L-23 CHILLER PLANT #2 AHU-22 SYSTEM The Outside Air Damper is set at 9,940 CFM. 60 CFM is exhausted continuously through the Gravity Relief Damper in the mezzanine floor. AHU-22 GRAVITY RELIEF DAMPER RD-22

CHILLER PLANT #2 AHU-22 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation Based on outside air enthalpy and outside air temperature, when less than 60°F AHU-22 operates in economizer cycle modulating the outside and return air dampers to maintain 60°F supply air temperature. LOCAL CONTROLLER DCS OUTSIDE AIR DAMPER CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation When outside air enthalpy and outside air temperature when less than 60°F, AHU-21 operates in economizer cycle modulating the outside and return air dampers to maintain 60°F supply air temperature. RETURN AIR DAMPER

CHILLER PLANT #2 AHU-22 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation Relief Air Damper RD-21 is controlled by differential pressure to maintain a 0.05 inch W.C. positive pressure in the building by modulating the damper. PRESSURE SENSOR A7 AT 0.05” W.C. RELIEF DAMPER RD-21 CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation Relief Air Damper RD-21 is controlled by differential pressure to maintain a 0.05 inch W.C. positive pressure in the building by modulating the damper. AHU-22

CHILLER PLANT #2 AHU-22 SYSTEM PLANT HVAC SYSTEMS CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation The chilled water valve to AHU-22 is closed during economizer cycle. In the event of damper failure or mixed air temperature below 35°F, a freezestat shuts down AHU-22 and sends an alarm. LOCAL CONTROLLER DCS FREEZESTAT CHILLER PLANT #2 AHU-22 SYSTEM Economizer Operation The chilled water valve to AHU-22 is closed during economizer cycle. In the event of damper failure or mixed air temperature below 35°F, a freezestat shuts down AHU-22 and sends an alarm. CHILLED WATER VALVE

What area is cooled by AHU-22? PLANT HVAC SYSTEMS QUESTION What area is cooled by AHU-22? Control Room Janitor’s closet Chemical Treatment Area Electric Room QUESTION What area is cooled by AHU-22? Control Room Janitor’s Closet Chemical Treatment Area Electric Room

AHU-22 cools the Electric Room. PLANT HVAC SYSTEMS ANSWER AHU-22 cools the Electric Room. ANSWER AHU-22 cools the Electric Room.

Where Is the Gravity Relief Damper located? PLANT HVAC SYSTEMS QUESTION Where Is the Gravity Relief Damper located? Control Room Mezzanine floor Electric Room Operating floor QUESTION Where Is the Gravity Relief Damper located? Control Room Mezzanine floor Electric Room Operating floor

The Gravity Relief Damper is in the mezzanine floor. PLANT HVAC SYSTEMS ANSWER The Gravity Relief Damper is in the mezzanine floor. ANSWER The Gravity Relief Damper is in the mezzanine floor.

What volume of cooling air is supplied to the Electric Room by AHU-22? PLANT HVAC SYSTEMS QUESTION What volume of cooling air is supplied to the Electric Room by AHU-22? 1,250 CFM 2,000 CFM 10,000 CFM 30,000 CFM QUESTION What volume of cooling air is supplied to the Electric Room by AHU-22? 1,250 CFM 2,000 CFM 10,000 CFM 30,000 CFM

AHU-22 supplies 10,000 CFM of cooling to the Electric Room. PLANT HVAC SYSTEMS ANSWER AHU-22 supplies 10,000 CFM of cooling to the Electric Room. ANSWER AHU-22 supplies 10,000 CFM of cooling to the Electric Room.

COOLING COIL CHILLED WATER VALVE PLANT HVAC SYSTEMS CHILLER PLANT #2 FCU-21 SYSTEM FCU-21 supplies 1,285 CFM of cooling to the Control Room, break room, office, and vestibule. Cooling is controlled by modulating the cooling coil chilled water valve in response to a temperature sensor in the Control Room. LOCAL CONTROLLER DCS CHILLER PLANT #2 FCU-21 SYSTEM FCU-21 supplies 1,285 CFM of cooling to the Control Room, break room, office, and vestibule. Cooling is controlled by modulating the cooling coil chilled water valve in response to a temperature sensor in the Control Room. COOLING COIL CHILLED WATER VALVE FCU-21A CONTROL ROOM COOLING COIL

ELECTRIC DUCT HEATER DH-21 PLANT HVAC SYSTEMS CHILLER PLANT #2 FCU-21 SYSTEM Outside air is set at 175 CFM during cooling with 1,110 CFM of return air. Heating is provided by a 6 KW Electric Duct Heater located in the supply air duct. ELECTRIC DUCT HEATER DH-21 CHILLER PLANT #2 FCU-21 SYSTEM Outside air is set at 175 CFM during cooling with 1,110 CFM of return air. Heating is provided by a 6 KW Electric Duct Heater located in the supply air duct. FCU-21

Where is the Electric Duct Heater located? PLANT HVAC SYSTEMS QUESTION Where is the Electric Duct Heater located? In the return air duct In the supply air duct In the relief air duct In the makeup air duct QUESTION Where is the Electric Duct Heater located? In the return air duct In the supply air duct In the relief air duct In the makeup air duct

The Electric Duct Heater is located in the supply air duct. PLANT HVAC SYSTEMS ANSWER The Electric Duct Heater is located in the supply air duct. ANSWER The Electric Duct Heater is located in the supply air duct.

Which of the following areas is cooled by FCU-21? PLANT HVAC SYSTEMS QUESTION Which of the following areas is cooled by FCU-21? Operating floor Chemical treatment area Electric Room Control Room QUESTION Which of the following areas is cooled by FCU-21? Operating floor Chemical treatment area Electric Room Control Room

PLANT HVAC SYSTEMS ANSWER FCU-21 supplies cooling to the Control Room, break room, office, and vestibule. ANSWER FCU-21 supplies cooling to the Control Room, break room, office, and vestibule.

OPERATIONS MONITORING PLANT HVAC SYSTEMS OPERATIONS MONITORING Operation of the Plant HVAC Systems is monitored through the Control Room on the top floor of Chilled Water Plant #2. OPERATIONS MONITORING Operation of the Plant HVAC Systems is monitored through the Control Room on the top floor of Chilled Water Plant #2.

PLANT ROUNDS PLANT ROUNDS PLANT HVAC SYSTEMS PLANT ROUNDS During an Operator’s routine shift, Rounds are accomplished to record key information and visually assess HVAC Water System operation. Each Plant has a Rounds Sheet to be filled out by the Operator. Each plant has different requirements for plant rounds. The information is recorded, not only for the current status, but also to record system trends. PLANT ROUNDS During an Operator’s routine shift, Rounds are accomplished to record key information and visually assess Chilled Water System operation. Each Plant has a Rounds Sheet to be filled out by the Operator. Each plant has different requirements for plant rounds. The information is recorded, not only for the current status, but also to record system trends.

EXAMPLE ROUNDS SHEET (front and back) PLANT HVAC SYSTEMS EXAMPLE ROUNDS SHEET (front and back) EXAMPLE ROUNDS SHEET (front and back)

HVAC DAILY ROUNDS HVAC DAILY ROUNDS Chiller Plants #1 and #2 PLANT HVAC SYSTEMS HVAC DAILY ROUNDS Chiller Plants #1 and #2 Outside temperature Outside humidity Outside enthalpy AHU (On/Off) Supply Fans (On/Off) Exhaust Fans (On/Off) HVAC DAILY ROUNDS Chiller Plants #1 and #2 Outside temperature Outside humidity Outside enthalpy AHU (On/Off) Supply Fans (On/Off) Exhaust Fans (On/Off)

HVAC DAILY ROUNDS HVAC DAILY ROUNDS West and East Campus Steam Plants PLANT HVAC SYSTEMS HVAC DAILY ROUNDS West and East Campus Steam Plants Outside temperature AHU Online/Offline Space temperature Supply air temperature Supply Fan HVAC DAILY ROUNDS West and East Campus Steam Plants Outside temperature AHU Online/Offline Space temperature Supply air temperature Supply Fan

HVAC DAILY ROUNDS HVAC DAILY ROUNDS West and East Campus Steam Plants PLANT HVAC SYSTEMS HVAC DAILY ROUNDS West and East Campus Steam Plants Exhaust Fan (not all exhaust fans are checked for all conditions) Online/Offline Space temperature Supply air temperature Firm alarm OK Gas alarm OK E-Stop alarm OK HVAC DAILY ROUNDS West and East Campus Steam Plants Exhaust Fan (not all exhaust fans are checked for all conditions) Online/Offline Space temperature Supply air temperature Firm alarm OK Gas alarm OK E-Stop alarm OK

TYPICAL PROBLEMS ASSOCIATED WITH PLANT HVAC SYSTEMS Stuck dampers Most likely cause is corrosion or debris Blocked coils Most likely cause is corrosion, faulty filters Malfunctioning control components Components damaged or out of calibration Clogged condensate drains Most likely cause is debris or damage to pipes TYPICAL PROBLEMS ASSOCIATED WITH PLANT HVAC SYSTEMS Stuck dampers Most likely cause is corrosion or debris Blocked coils Most likely cause is corrosion, faulty filters Malfunctioning control components Components damaged or out of calibration Clogged condensate drains Most likely cause is debris or damage to pipes

Where does Operations Monitoring take place? PLANT HVAC SYSTEMS QUESTION Where does Operations Monitoring take place? Control Room in each steam plant Control Room in West Campus Steam Plant Control Room in Chilled Water Plant #2 Control Room in Chilled Water Plant #1 QUESTION Where does Operations Monitoring take place? Control Room in each steam plant Control Room in West Campus Steam Plant Control Room in Chilled Water Plant #2 Control Room in Chilled Water Plant #1

PLANT HVAC SYSTEMS ANSWER Operations Monitoring takes place In the Control Room in Chilled Water Plant #2. ANSWER Operations Monitoring takes place In the Control Room in Chilled Water Plant #2.

Which air pressure condition in a building is preferable? PLANT HVAC SYSTEMS QUESTION Which air pressure condition in a building is preferable? Under Pressure Over Pressure Balanced Air pressure is not a concern of HVAC QUESTION Which air pressure condition in a building is preferable? Under Pressure Over Pressure Balanced Air pressure is not a concern of HVAC

PLANT HVAC SYSTEMS ANSWER Operations Monitoring takes place In the Control Room in Chilled Water Plant #2. ANSWER Operations Monitoring takes place In the Control Room in Chilled Water Plant #2.