the integrated boiler room - home - yorkland controls ltd · · 2013-09-23the integrated boiler...

www.yorkland.net Yorkland Controls 1

The Integrated Boiler RoomGerry Cellucci Yorkland Controls

[email protected]


Control Objectives for Hydronic systems

Maximize Occupant ComfortMaintain Constant Space Temperature

Minimize Energy ConsumptionMinimize boiler temperatureMinimize Boiler Cycling (on/off)

ProtectionMinimum Boiler Temperature MaintainedBoilers NOT to be Cycled on Limits


Boiler Room Control TrendsAway from individual control of various heating loops:

Main Heating LoopSecondary Heating LoopsDomestic Hot WaterSnow Melting

Owners requesting operational informationTrendsStatusAlarms

Reduce operating costs and increase efficiency


Typical Boiler Room ControlsControl for Boiler sequencingControl(s) for “resetting” Hotwater based on outside air temperatureDomestic Hotwater Air Handler Heating Coil LoopsRadiant Heating LoopsDifferential Pressure Time clocks for setback


Boiler 1 Boiler 2

MIX

ING

VAL

VE

P1

P2

BP1

BP2

HWS MAIN BOILER LOOP

HWR

HWR

HWS TO ZONES

T

T-360

OA-T

P3

T

T

HEX P4

DHW TANK

T

T

N 0

CNC

DHW-VLV

Sequencer

Reset MainReset

DHW

Pump

Circ Pumps

DHW


Current ControlDifferent controls for the various loopsDuplicate Sensors for the same function (Outdoor Air temp)Difficult to coordinate setpointsLimited Control LogicLimited DiagnosticLimited AlarmingMinimal Energy Savings


Boiler Reset - What is it?

Water temperature is varied based on outside temperatureHeat loss from building changes continuously -not on/offControl matches heat loss of building to heat

output of boiler (or mixing valve)


Boiler Reset - BenefitsReduced heat loss through pipes. (Standby Losses reduced)

Increased boiler efficiency.(Boilers more efficient at lower fire)

Elimination of uncomfortable (and expensive) overheating. Boiler shutoff when it's not needed.


Boiler ResetHotwater supply temperatures are RESET based on outside air. Goal is to reduce the seasonal average control temperature.Typical reset schedule

OA-T = 0 F HWS-T = 185OA-T = 65 F HWS-T = 135

Savings calculation are often derived from estimates Studies to show minimum 10% to 12 % savings


Building Reset TypesBoiler Temperature ResetMixing Reset ( Building Loop )


Typical Reset Products

T775 HoneywellA350R JohnsonTekMarDx9100

Increasing Features


Typical Reset SchedulesMain Boiler

Radiation

13055

HWS-T

190OA-T

-10

10055

HWS-T

180OA-T

0

Usually expressed as a Ratio


Outdoor Air Temperature

Hotw

ater Supply

200

-10

130

60

What is the Ratio ?


Boiler SequencingLead-Lag

Boilers run 1,2,3,4 then 4,3,2,1Switching inputUsually set with a manual or time clock

Rotational Boilers run in logical order on the next firing cycle: 1,2,3,4, then 2,3,4,1 then 3,4,1,2, then 4,3,2,1

Equal Run TimeBoiler with the least amount of “ON” time is first on.


Integrated Control Benefits(all functions in one common interface)

Multiple Boiler Sequencing:Lead-LagRotationalEqual Run Time

Shared SensorsMultiple Control Loops (PID)Different Reset Ratios for various loadsPump ControlPost-Purge Pump ControlAnti – Condensation ProtectionTrending for Major ParametersOccupied Time schedule common for all the control loops


Benefits One location for the informationMicroprocessor basedEasy to use customizable displayNetworkableCentralized Alarms

PagerMobile PhoneE-Mail


Boiler 1 Boiler 2

MIX

ING

VAL

VE

P1

P2

BP1

BP2

HWS MAIN BOILER LOOP

HWR

HWR

HWS TO ZONES

T

T-360

OA-T

P3

T

T

HEX P4

DHW TANK

T

T

N 0

CNC

DHW-VLV

Sequencer

Reset MainReset

DHW

Pump

Circ Pumps

DHW


Integration withGeneric Controls

Custom Control LoopsSame Controller for different types of heating or cooling systemsEasy to duplicate programs


Generic ContolUses Software to set up the control loopsSame software is used to commission


Typical Controllers


Generic Control Features10 – 12 PID Control Loops with enhanced capabilitiesStart/Stop LoopsLogic LoopsMath FunctionsSequencing functionsPulse inputs for flow meters8 Digital Inputs, 8 Digital Outputs8 Analog Inputs, 6 Analog OutputsExpandable I/O’s


RESET SCHEDULE TYPICAL

-5 0

65 70

185 185

135 135

-50

0

50

100

150

200

OUTDOOR AIR TEMP DEG F

HO

TWA

TER

SU

PPLY

TEM

PC

ALC

ULA

TED

OUTDOOR AIR -5 0 65 70

HOT WATER SETPOINT(CALCULATED)

185 185 135 135

1 2 3 4

X0

Y0

X1

Y1

X2

Y2

X3

Y3


Reset Control Strategy

Reset Schedule (ratio) calculates the Hot water temp SETPOINTSETPOINT is compared to ACTUAL Hot water tempDIFFERENCE compared to the “proportional band” (throttling band) parameter determines the amount of heating capacity required (expressed as a %)


Reset Strategy - Example

Calculated Hotwater Setpoint = 165 FActual Hotwater Temperature = 155 FProportional Band Set = 30 F% Heating Capacity = 33%


Boiler Capacity & Proportional Band Relationship

% Heating Capacity Required

100 %

50 %

Calculated Setpoint

Proportional Band = 30 F

15 F

165 F

Actual HW Temp155 F

33 %

Hot Water Temperature

One Boiler - 3 Stages each stage having equal capacity

One stage is ON


Boiler Reset –Load Compensation

Direct Feedback of Buildings’ Heat LoadBoiler Capacity is adjusted by using Return Water or Space Temperature as Feedback

Capacity is reduced as Space temperature approaches space comfort (72F)Capacity is reduced as Return Water approaches Supply Water

New Effective Set point is used to determine Capacity


Boiler Capacity & Proportional Band Relationship

% Heating Capacity Required

100 %

50 %

ReferenceSetpoint 165 F

Proportional Band = 30 F

15 F

Effective Setpoint163.5 F

Actual HW Temp155 F

33 %

Hot Water Temperature

25 %

One Boiler - 3 Stages each stage having equal capacity

One stage is OFF

Proportional Band Increased = 40 F


Simply…………Load Compensation accounts for internal heat load by staging boilers -“OFF” SOONER & “ON” LATER…...….in a smooth controlled manner. (no cycling of the boilers)


Estimated Reset SavingsAverage reduction in boiler temp 25 F with basic reset

10% to 15% SavingsAverage reduction in boiler temp 30 F with load compensation additional

7% to 15%Utilities offering Rebates


Other Control System Features

Variable Stage CyclingEqual wearLow-Med-High or Low-Low-Low Firing

Season “Soft-Start” of Building Loop ValveBoiler Circulating Pump Run TimeCharacterized Reset Schedule

Match radiation equipmentFinned TubeFan CoilsDHW Production


Boilers Efficient at Low to Mid Load


Firing Sequence• Low - Medium - High (3 to 4 stages per boiler)

•Low – Low – Low

•Equal Run Time


Characterized Heating Curve

• Different types of terminal units transfer heat to the space at different proportions of radiation, and convection

• Water supply temperature is controlled by the type of terminal unit


Terminal Unit Types


RESET SCHEDULE "Characterized"

-10 -5 0 10

55 60 70

190 187 185170

140 130 130

-50

0

50

100

150

200

OUTDOOR AIR TEMP DEG F

HO

TWA

TER

SU

PPLY

TE

MP

CA

LCU

LATE

D

OUTDOOR AIR -10 -5 0 10 55 60 70

HOT WATER SETPOINT(CALCULATED)

190 187 185 170 140 130 130

1 2 3 4 5 6 7

X0

Y0

X1

Y1

X2

Y2

X3

Y3


Dx9100 Generic ControllerExample


Boiler Product for Intergrated Heating Plants

Johnson Dx9100 Configurable ControllerAllows for Flexibility in Control Strategy

Standard Reset CurveCharacterized curve

Integral Boiler ControlMain Hot waterBuilding LoopDomestic Hot water

Allows for Load Compensation Strategy ChangeSpace sensing for small facilitiesReturn Water sensing for larger systems

Maybe networked and monitoredOver 90 contractor individuals trainedProduct Stocked and supported


Typical Projects MTHA

P5-CP5-STS

P7-CP7-STS

P6-CP6-STS

P10-CP10-STS

P3-CP3-STS

P2-CP2-STS

P4-CP4-STS

B3HI-CB3LO-C

B2HI-CB2LO-C

TAN

K-T

HIG

H

B1HI-CB1LO-C

BP 4

B4 BP 3

B3 BP 2

B2 BP 1

B1

P1

P4

LOO

P 3-T

P10

TAN

K-T

LOW

P9

P2

LOO

P 1-T

V2

P3

LOO

P 2-T

DHW LOWPRESSURE

HW

S-T H

WR

-T

B4HI-CB4LO-C

HWR HWR

DHW HIGHPRESSURE

HEX 2 HEX 1

V4P5

P8

V5

P6

V3

P7

V1

HWS HWS

BP 1-STSBP 2-STSBP 3-STSBP 4-STS

P1-CP1-STS

P9-CP9-STS

P8-CP8-STS


Intergrated Boiler Control Room


Diagnostic Exercise 1HWS -T = 178FHWR -T = 172FWhat assumptions can you make?

Load ?


Diagnostic Exercise 2HWS-T = 170 (current reading)HWR-T = 160 (current reading)Setpoint = 185Trend showed:

HWS-T = 198FHWR-T = 180F

2 out of 4 Boilers not firing ????


Diagnostic Exercise 3HWS-T = 170HWR-T = 175

???


Diagnostic Example 4OA-T = 0 FHWS-T = 185HWR-T = 160All boilers on and firing

????


Service TipsFamiliarize yourself with the systemReview diagnostic information Check Trending info (if available)Make sure equipment is functioningCheck sensors and relays

Most outputs from controllers are TRIAC with Pilot Relays

Software would be nice to have – BUT NOT necessary – use the display?


Tools of the Controls Trade ?Supplier Commissioning Software

Allows you to verify operation and get all parameters

Laptop or Display DeviceControl Logic ExperienceUnderstand the control terms

PIDDead Bands


Typical Cost - Conventional8 Stage Boiler Control $ 1890

Lead/Lag / PumpReset Control w/Pump $ 750 (250x3)Lead/Lag Pump Control $ 400Domestic w/ VLV output $ 400Time Clock $ 60

Total $ 3,500.00


Integrated Controller System

Controller $ 1400Sensors $ 400Panel $ 250Programming $ 500TOTAL $ 2550.00

Display(optional) 750.00 Software 500.00Hardware 100.00


Questions


Thank You

the integrated boiler room - home - yorkland controls ltd · · 2013-09-23the integrated boiler...

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