Duke
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Steam Heating System
DU-101-PP
STEAM HEATING SYSTEM
 PURPOSE
 The purpose of the Operations and Maintenance Training Program is to
train Operations and Maintenance Technicians in the operation of the
Duke University Chiller and Steam Systems.
 OBJECTIVES
 Trainees will demonstrate knowledge of
– Steam Heating System Components
– Steam Heating System Components Operation
– Steam Heating System Configuration
– Steam Heating System Controls and Instrumentation
Duke
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STEAM HEATING SYSTEM
 PURPOSE
 The purpose of the Steam Heating System is to provide climate control for
all East Campus, West Campus, and Duke Medical Center buildings.
 STEAM HEATING SYSTEM
 Boilers in the East Campus Steam Plant and the West Campus
Steam Plant supply steam to the Underground Seat and
Condensate Distribution System.
 The Control Room assures a steady supply of steam to all facilities,
bringing boilers online as they are needed and taking boilers offline
to accommodate pressure requirements and equipment
maintenance.
 In the campus buildings, a Pressure Reduction Valve (PRV) Station
reduces steam pressure to levels suitable for heating and other
services.
Duke
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STEAM HEATING SYSTEM
 WHY STEAM?
 Steam is an efficient and easily controlled heat transfer medium.
 Heat from the boilers is stored in the steam until it is processed in the
building air handlers.
 Steam transports energy from the boilers to any number of remote
locations with minimal loss of energy.
 Both steam plants serve a common distribution system, which ensures a
steady supply of steam to all facilities while boilers and other equipment
are taken offline:
– To provide access for maintenance without interrupting service
– To improve equipment life
– To enable the most efficient use of resources
Duke
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STEAM HEATING SYSTEM
 HEAT TRANSFER PRINCIPLES
 Boilers raise water temperature enough above the boiling point to
produce ‘saturated’ steam.
 The temperature of latent heat in the saturated steam is maintained until
the steam releases its latent heat into the coils of a heat exchanger.
LATENT HEAT
SATURATED
STEAM
CONDENSATE
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STEAM HEATING SYSTEM
 Heat naturally flows from a higher temperature level to a lower
temperature level. This is known as heat transfer.
 The purpose of the distribution system is to convey steam from the boilers
to the heat exchange with minimal loss of latent heat along the way.
 Pipe walls, condensate film, condensate drops, air film, scaling, and even
the insulation on the outside of the pipe all cause some heat loss and
condensation. To maintain necessary pressure, the boiler has to work
harder.
 The effects of these factors on heat transfer can be minimized by:
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Duke
Drip Leg Stations at regular intervals to remove condensate from the piping.
Monitoring pressure.
Regular maintenance to remove scale and other damage to the pipes.
Conditioning feed water used in the boiler to ensure the steam generated in
the boiler is as pure as possible.
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STEAM HEATING SYSTEM
 CONDENSATE RETURN PRINCIPLES
 Condensate is the byproduct of heat transfer in the Steam Heating System.
 Condensation forms in distribution piping and heating equipment.
 As condensation forms in the underground piping, it is separated from the
steam in drip leg stations and returned to the plant where it will be used
to preheat feed water.
 At a campus building, after steam has condensed and given up its valuable
heat in the air handler’s heat exchanger, the hot condensate is pumped
back to the boiler before it can cool.
 The hot condensate is used to preheat feed water before it enters the
boiler, which helps the boiler run efficiently.
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Why is condensate returned to the plant?
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Duke
For disposal
To preheat feed water
To fill the water towers
To absorb steam
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STEAM HEATING SYSTEM
 ANSWER
 To preheat feed water
Duke
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STEAM HEATING SYSTEM
 QUESTION
 How does heat flow?
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Duke
Lower temperature to higher temperature
Higher temperature to lower temperature
Heat does not flow
Downhill
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STEAM HEATING SYSTEM
 ANSWER
 Higher temperature to lower temperature
Duke
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STEAM HEATING SYSTEM
 QUESTION
 How is saturated steam made?
– Water is heated enough above the boiling point to produce
steam
– Water is heated to boiling
– Steam is mixed with hot water
– Steam is cooled slowly to remove water
Duke
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STEAM HEATING SYSTEM
 ANSWER
 Water is heated enough above the boiling point to produce
steam
Duke
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STEAM HEATING SYSTEM
 PURPOSE
 The systems that make up the Steam Heating System work together to
provide a reliable and and efficient heat source for the East and West
Campuses and Medical Center.
Duke
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STEAM HEATING SYSTEM
 SYSTEMS
 The Duke University Steam Heating System includes the following
equipment and locations:
– High Pressure Steam System
• East Campus Steam Plant
• West Campus Steam Plant
– Underground Steam and Condensate Distribution System
• Steam from the East Campus Steam Plant and West Campus Steam Plant
is fed into the Underground Steam and Condensate Distribution System
• Reaches all Duke University facilities
– Medium Pressure and Low Pressure Steam System
• Located inside all Campus and Medical Center buildings
• Converts high pressure steam to medium pressure steam for services and
low pressure steam for heating.
Duke
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STEAM HEATING SYSTEM
 HIGH PRESSURE STEAM SYSTEM
 High Pressure Steam Headers are located in the East Campus Steam Plant
and the West Campus Steam Plant.
EAST CAMPUS STEAM PLANT
Duke
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STEAM HEATING SYSTEM
 HIGH PRESSURE STEAM HEADER
 Sensors at the HPS Header send data on the steam to the Control Room.
Duke
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STEAM HEATING SYSTEM
 EAST CAMPUS STEAM PLANT
Duke
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STEAM HEATING SYSTEM
 WEST CAMPUS STEAM PLANT
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Where are HPS Headers located?
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Duke
East Campus and West Campus Steam Plants
All steam and chiller plants
Campus and Medical Center buildings
Chiller Plants 1 and 2
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STEAM HEATING SYSTEM
 Answer
 East Campus and West Campus Steam Plants
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What is the nominal pressure of steam leaving the HPS
Header?
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Duke
75 psig
Less than 16 psig
125 psig
170 psig
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STEAM HEATING SYSTEM
 ANSWER
 125 psig
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Which boilers in a Steam Plant supply the High Pressure
Steam Header?
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Duke
All boilers all the time
Each boiler has its own HPS Header
All boilers that are on line
All boilers that are offline
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STEAM HEATING SYSTEM
 ANSWER
 All boilers that are on line
Duke
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STEAM HEATING SYSTEM
 UNDERGROUND STEAM AND CONDENSATE DISTRIBUTION
SYSTEM
 PURPOSE
– The Underground Steam and Condensate Distribution System
conveys high pressure saturated steam to buildings throughout
the Duke University Campus and Medical Center
– The nominal steam pressure is 125 psig
Duke
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STEAM HEATING SYSTEM
 UNDERGROUND STEAM AND CONDENSATE DISTRIBUTION
SYSTEM
 COMPONENTS
– Underground Piping
• The majority of piping is buried.
• Steam Vaults (manholes provide access points and junctions for
buried pipes.
• There are approximately 35 miles of underground piping.
– Three-pipe design
• High Pressure Steam (HPS) supply piping delivers steam to
buildings.
• Pumped Condensate (PC) return piping conveys hot
condensate drained from air handlers back to the plant.
• High Pressure Condensate (HPC) return piping sends
condensate removed from the High Pressure Steam piping to
the plant to be used as make-up feed water.
Duke
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STEAM HEATING SYSTEM
 COMPONENTS
– Tunnels provide access to piping that is not buried
• Tunnels are tall enough to allow personnel to walk upright
• Access is provided for maintenance of piping, valves, and
instrumentation
• Valves are provided to isolate segments of the system
Duke
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STEAM HEATING SYSTEM
 COMPONENTS
– Steam Vaults (Manholes)
• Steam Vaults are located at no more than 300-foot intervals in
underground piping
• HPS Supply side of Steam Vault
– 36 inch manhole lid
– Drip Leg Station drains and cleans condensate from HPS Supply
• PC Return side of Steam Vault
– 24 inch manhole lid
– Sump pit provides drainage (with an electric sump pump, when
gravity drainage is not adequate
• Junction(s)
– Steam Vaults can contain junctions to connect branches of
piping
– HPS Supply and PC Return lines can be joined in a Steam
Vault in various configurations
– Not all Steam Vaults contain junctions
Duke
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STEAM HEATING SYSTEM
 COMPONENTS
– Drip Leg Stations
• Drip Pocket drains condensate from steam lines.
• Strainer removes dirt and particulates from condensate.
– Steam Entry Pits
• Located beneath each Campus and Medical Center building.
• HPS Supply enters from the Underground Steam and Condensate
Distribution System.
• Steam pressure is reduced at the PRV Station.
• Condensate from air handlers drains by gravity into the sump in
the Steam Entry Pit.
• Condensate in the sump pit is returned to the Underground Steam
and Condensate Distribution System by the sump pump.
Duke
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STEAM HEATING SYSTEM
 PIPING
 Three Pipe System
– High Pressure Steam (HPS Supply)
– High Pressure Condensate (HPC Return)
– Pumped Condensate (PC Return)
DRIP LEG STATION
MANHOLE
Duke
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STEAM HEATING SYSTEM
 THREE PIPE SYSTEM
 HPS Supply carries steam from the plant to
Campus and Medical Center buildings.
DRIP LEG STATION
MANHOLE
HPS SUPPLY
Duke
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STEAM HEATING SYSTEM
 THREE PIPE SYSTEM
 Condensate removed from HSP Supply at the Drip
Leg Station is returned to the Steam Plant in the
HPC Return piping.
HPC RETURN
DRIP LEG STATION
Duke
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MANHOLE
STEAM HEATING SYSTEM
 THREE PIPE SYSTEM
 Condensate from air handlers is pumped from
buildings to the Steam Plant through the PC
Return piping
PC RETURN
DRIP LEG STATION
MANHOLE
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What are the three pipes in the three pipe design?
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Duke
HPS Supply, HPC Return, PC Return
HPS Return, HPC Supply, PC Return
LPS Supply, HPS Supply, PC Return
PC Supply, PRV Return, HPS Supply
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STEAM HEATING SYSTEM
 ANSWER
 35 miles
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Approximately how much piping is in the Underground Steam
and Condensate Distribution System?
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Duke
300 feet
50 miles
35 miles
900 yards
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STEAM HEATING SYSTEM
 ANSWER
 HPS Supply, HPC Return, PC Return
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What is carried in PC Return piping?
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Duke
Condensate from building
Steam from Plant
Condensate from Drip Leg Station
LPS from PRV Station
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STEAM HEATING SYSTEM
 ANSWER
 HPS Supply, HPC Return, PC Return
Duke
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STEAM HEATING SYSTEM
 TUNNELS
 Provide easy access to the Underground Steam and
Condensate Distribution System to personnel
– Maintaining piping, valves, sensors, and controls
– Isolating segments of the system
Duke
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STEAM HEATING SYSTEM
 UNDERGROUND PIPING
 The majority of piping is buried.
 Steam Vaults (manholes) provide access and junction points
Duke
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STEAM HEATING SYSTEM
 STEAM VAULTS
 HPS supply side of the vault
 36 inch Manhole provides access for maintenance
 Drip Leg Station drains and cleans condensate from HPS
 PC return side of the vault
 24 inch Manhole provides access for maintenance of
condensate return piping
 Sump pit provides drainage of condensate lost from the the
system
 Junction
 HPS supply and PC return from various lines can come together
in a steam vault
Duke
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STEAM HEATING STATION
 STEAM VAULT
 HPS Supply Side
MANHOLE
 Drip Leg Station
 36 inch Manhole for maintenance
access
HIGH PRESSURE STEAM
DRIP LEG STATION
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STEAM HEATING SYSTEM
MANHOLE
 STEAM VAULT
 PC Return Side
 24 inch manhole lid for maintenance
access
 Sump with Pump
MAIN PC RETURN
SUMP PUMP
SUMP
Duke
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STEAM HEATING SYSTEM
 STEAM VAULT
 Top View of Junction
HPS SUPPLY BRANCH
PC RETURN BRANCH
MAIN HPS SUPPLY
MAIN PC RETURN
PC MANHOLE
Duke
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HPS MANHOLE
STEAM HEATING SYSTEM
 STEAM VAULT DRIP LEG STATION
 Drip Pocket
 Strainer
 Steam Trap
HPS SUPPLY
ISOLATION VALVES
DRIP POCKET
TO HPC RETURN
BLOWDOWN TEST TEE
STEAM TRAP
STRAINER
BLOWDOWN DRAIN
Duke
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STEAM HEATING STATION
 STEAM VAULT DRIP LEG STATION
 Drip Pocket
– Condensate forming as steam cools can cause water hammer, erosion and
scaling of pipe, and pipe and equipment failure
– Condensate drops out of the stream as steam passes over the drip pocket.
HPS SUPPLY
DRIP POCKET
CONDENSATE
Duke
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STEAM HEATING SYSTEM
 STEAM VAULT DRIP LEG STATION
 Strainer
 Condensate from the drip pocket passes through the strainer
 Fine mesh screen collects dirt and particulates
DRIP POCKET
SCREEN
STRAINER
Duke
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STEAM HEATING SYSTEM
 STEAM VAULT DRIP LEG STATION
 Stream Trap
 Air and CO2 separate from the condensate and collect in the inverted bucket.
 When the inverted bucket becomes buoyant, the bucket rises, triggers the valve
above the bucket, and the gases vent out the top of the Steam Trap.
VALVE
INVERTED BUCKET
CONDENSATE FROM STRAINER
TO HPC RETURN
Duke
STEAM TRAP
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STEAM HEATING SYSTEM
 QUESTION
 What does a Drip Leg do?
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Duke
Removes gases from HPS Supply
Drains and cleans condensate from HPS Supply
Pumps condensate from the Steam Pit Entry
Detects leaks in underground piping
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STEAM HEATING SYSTEM
 ANSWER
 Drains and cleans condensate from HPS Supply
Duke
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STEAM HEATING SYSTEM
 QUESTION
 The majority of piping is where?
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Duke
In tunnels
Buried
Overhead
Underwater
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STEAM HEATING SYSTEM
 ANSWER
 Buried
Duke
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STEAM HEATING SYSTEM
 QUESTION
 HPS supply is connected to HPS Return by what?
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Duke
PRV Station
Junction
Drip Leg Station
Steam Vault
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STEAM HEATING SYSTEM
 ANSWER
 Drip Leg Station
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What are Steam Vaults also known as?
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Duke
Steam Entry Pits
Manholes
Deaerators
Steam Traps
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STEAM HEATING SYSTEM
 ANSWER
 Manholes
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What does a Steam Trap do?
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Duke
Reduces steam pressure
Captures steam for testing
Removes air and CO2 from condensate
Removes dirt and particles from steam
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STEAM HEATING SYSTEM
 ANSWER
 Removes air and CO2 from condensate
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What does a Steam Vault do?
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Duke
Holds steam until it is needed
Provides access to underground piping
Serves as an entry point for HPS Supply into a building
Removes steam from condensate lines
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STEAM HEATING SYSTEM
 ANSWER
 Provides access to underground piping
Duke
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STEAM HEATING SYSTEM
 LOW PRESSURE AND MEDIUM PRESSURE STEAM SYSTEM
– Steam Pit Entry is the vault beneath each building where HPS Supply
enters the building and PC Return leaves.
– The PRV Station in each building reduces high pressure steam (125
psig) to medium pressure steam\ (75 to 16 psig, and medium pressure
steam to low pressure steam (less than 16 psig).
– Medium pressure steam is used for building services washing hot
water, and other services).
– Low pressure steam is used by air handlers to heat the building.
– Condensate from the air handlers flows to the sump pit by gravity. The
condensate pump sends condensate to the plan through the PC
Return piping.
Duke
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STEAM HEATING SYSTEM
 STEAM PIT ENTRY
– Entry point for Buildings
– Maintenance access
– Drip Leg removes
condensate
– Condensate Pump
returns condensate to
Steam Plant
DRIP LEG
CONDENSATE PUMP
Duke
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STEAM HEATING SYSTEM
 PRV Station
 Reduces pressure in buildings in two stages
– HPS Supply to Medium Pressure Steam (MPS) for services
– MPS to Low Pressure Steam (LPS) for heating
MPS TO SERVICES
HPS FROM STEAM PLANT
LPS TO HEATING
PRV
Duke
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STEAM HEATING SYSTEM
 PRV STATION
 PRV
– PRV uses adjustable spring and
diaphragm design to reduce
steam pressure.
– The PRVs in the first stage of
the PRV Station reduce steam
pressure from 125 psig (HPS) to
75 to 16 psig (MPS)
– The PRVs in the second stage of
the PRV Station reduce steam
pressure from 75 to 16 psig to
less than 16 psig (LPS).
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What does a PVR Station do?
– Reduces pressure so steam can be used for services and heating
– Pumps condensate from the air handlers
– Increases steam pressure so steam can reach the most remote air
handlers
– Converts steam to hot condensate
Duke
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STEAM HEATING SYSTEM
 ANSWER
 Reduces pressure so steam can be used for services
and heating
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What is LPS used for?
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Duke
Reducing pressure from HPS Supply
Heating
Hot water
Pumping condensate back to the plant
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STEAM HEATING SYSTEM
 ANSWER
 Heating
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Which of these is MPS used for?
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Duke
Reducing pressure from HPS Supply
Heating
Hot water
Pumping condensate back to the plant
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STEAM HEATING SYSTEM
 ANSWER
 Hot water
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What does a PRV do?
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Duke
Reduces voltage to the condensate pumps
Reduces steam pressure
Converts condensate to steam
Removes air and CO2 from steam
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STEAM HEATING SYSTEM
 ANSWER
 Reduces steam pressure
Duke
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STEAM HEATING SYSTEM
STEAM HEATING SYSTEM CONFIGURATION
AND PROCESS FLOW
Duke
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STEAM HEATING SYSTEM
 HPS HEADERS, EAST AND WEST STEAM PLANTS
 Steam from boilers is regulated in HPS Header
 Header supplies HPS to Underground Steam and Condensate Distribution
System
 Steam pressure exiting plant is 125 psig
HPS HEADER
UNDERGROUND PIPING
BOILERS
Duke
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STEAM HEATING SYSTEM
 STEAM VAULT
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HPS steam enters Steam Vault
Condensate drains into Drip Pocket
Steam Trap removes air and CO2
Strainer removes dirt and particulates
STEAM VAULT
DRIP LEG STATION
STEAM TRAP
Duke
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STEAM HEATING SYSTEM
 STEAM ENTRY PIT
 HPS enters Campus and Medical Center buildings at Steam Entry Pit
 Drip Leg removes condensate
DRIP LEG
STEAM ENTRY PIT
Duke
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STEAM HEATING SYSTEM
 PRV STATION
 HPS is reduced to MPS, 75 to 16 psig
75-16 psig
 MPS is reduces to LPS, less than 16 psig
 LPS is sent to the building heating system
PRV STATION
125 psig
Duke
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> 16 psig
STEAM HEATING SYSTEM
 STEAM ENTRY PIT
 Condensate from heat heating goes to the Condensate Pump
 Condensate is returned to the Steam Plant
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What is the function of the Steam Pit Entry?
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Duke
Where HPS Supply enters a building
Entrance to Steam Vault
Contains the LPS Station
Contains air handlers
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STEAM HEATING SYSTEM
 ANSWER
 Where HPS Supply enters a building
Duke
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STEAM HEATING SYSTEM
 QUESTION
 Steam from boilers enters the distribution system where?
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Duke
PRV Station
HPS Header
Steam Pit Entry
Steam Vault
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STEAM HEATING SYSTEM
 ANSWER
 HPS Header
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What is the pressure of low pressure steam?
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Duke
Below 16 psig
16 psig
75 psig
24 psig
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STEAM HEATING SYSTEM
 ANSWER
 Below 16 psig
Duke
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STEAM HEATING SYSTEM
 QUESTION
 In what part does the Drip Leg Station collect condensate
from HPS Supply?
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Duke
The Drip Leg Station does not collect condensate
Steam Trap
Strainer
Drip Pocket
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STEAM HEATING SYSTEM
 ANSWER
 Drip Pocket
Duke
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STEAM HEATING SYSTEM
 QUESTION
 What does the strainer do?
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Duke
Removes air and CO2 from condensate
Removes LPS from HPS Supply
Removes dirt and particulates from condensates
Removes latent energy from HPS Supply
Facilities Management
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STEAM HEATING SYSTEM
 ANSWER
 Removes dirt and particulates from condensate
Duke
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STEAM HEATING SYSTEM
 OPERATIONS MONITORING
– Operation of the Steam Heating System at Duke University is
monitored through the Control Room, at West Campus Chilled Water
Plant #2.
– The Digital Control System (DCS) provides operators with information
on system operation and control over system parameters.
Duke
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STEAM HEATING SYSTEM
 PLANT ROUNDS
– During an Operator’s routine shift, Rounds are accomplished to record
key information and visually assess Steam Heating System operation,
as well as other systems in the Steam Plants.
– Each Steam Plant has a Round 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.
Duke
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STEAM HEATING SYSTEM
 WEST PLANT
– The following is recorded, during operator rounds, for the West Plant, at 0800,
1600, 2000, and 0400 hours:
• Steam header PSI
• DA steam PSI/water temperature
• Steam flow, drum PSI, and gas/fuel Oil PSI to Boilers 1, 2, 3, 6
• Steam flow, drum PSI, fuel oil PSI to BLR, and atomizing steam for boilers 4
and 5
• City water PSI
• C/W booster pump online, and pump outlet PSI
• Softeners online
• FWP online, and discharge PSI
• Plaint air PSI
• Air storage tank PSI
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STEAM HEATING SYSTEM
 WEST PLANT
– The following is recorded, during operator rounds, for the West Plant, at 0800,
1600, 2000, and 0400 hours:
• Air compressor online, PSI, and temp
• Generator (volts/temp)
• Condensate pumps online, and discharge PSI
• Tunnel condensate pumps leaking
• Cond economizer rounds
• Fan status, pump online, water level, flue gas temp in/out, makeup temp
to V01, makeup temp to HA-02, condensate temp leaving HA-01
• Glycol system
• Pump online, inlet/outlet PSI, glycol inlet/outlet temp, CHW inlet/outlet
temp
• Chemical pumps rounds (day shift only)
• Softeners rounds (day shift only)
• Fuel oil/SPCC rounds day shift only
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STEAM HEATING SYSTEM
 EAST PLANT
– The following is recorded, during operator rounds, once on dayshift, and once on
nightshift:
• Deaerators
• Pressure, steam temp, water temp, PC bypass closed
• Heating water pumps
• Suction/discharge PSI
• HP steam to DA
• Top/bottom PSI
• Steam letdown
• Top/bottom PSI, SF#1 breaker on/off
• Rooftop
• Breakers
• Operating Floor
• Leak detector, NG/propane valve, HRS inlet/outlet water temp, HRS drain
water temp, HRS soft water inlet/outlet PSI, blowoff tank outlet temp
• Rooftop
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STEAM HEATING SYSTEM
 EAST PLANT
– The following is recorded, during operator rounds, once on dayshift, and once
on nightshift:
• Breakers
• Basement area
• Steam header PSI, city water inlet PSI, city water PSI after strainer, vacuum
skid sight glass, pumps 5-8, booster pumps 1 and 2, HP drip station, fire
water system, sump pump station, AHU-1 breaker
• Fan room
• SF-2-SF-4 breakers: valves open, AHU-2 breakers: valves open
• Outside building
• Condensate tank levels, natural gas piping, propane skid, vaporizer,
emergency generator, propane unloading area
• Night Shift Only: Softeners online, GMPs, polishers online, boiler 1-15,
chemical pump, softeners, and brine tank
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STEAM HEATING SYSTEM
 EXAMPLE WEST PLANT ROUNDS SHEET (front and back)
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STEAM HEATING SYSTEM
 EXAMPLE EAST PLANT ROUNDS SHEET (front and back)
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STEAM HEATING SYSTEM
 TYPICAL PROBLEMS ASSOCIATED WITH THE STEAM HEATING SYSTEM
– Clogged Strainer
• Most likely cause is mesh strainer is full of debris.
– Failed Steam Trap
• Most likely cause is failure or clogging of vent.
– Flooding of Steam Vault or Steam Entry Pit
• Most likely cause is sump pump has failed or drain is clogged.
– Failed PRV
• Most likely cause is clogged valve, degraded diaphragm, or spring
requires adjustment
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STEAM HEATING SYSTEM
 QUESTION
 Where does Operations Monitoring take place?
–
–
–
–
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Control Room in each steam plant
Control Room in West Campus Steam Plant
Control Room in Chiller Plant #2
Control Room in Chiller Plant #1
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STEAM HEATING SYSTEM
 ANSWER
 Control Room in Chiller Plant #2
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