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Grundfos FLOW THINKINGAir conditioningtheGrundfos Way

Grundfos FLOW THINKINGObtainable energy saving1. Constant pressure2. Constant diff. pressure3. Proportional diff. pressure(calculated)4. Proportional diff. pressure(measured)5. Temperature controlHEffect in %100806040201.2.3.4.5.00 20 40 60 80 100Flow in %25%100% Q

Grundfos FLOW THINKINGOptimized operation costOptimized operation cost often means LOWER ENERGY COSTAn effective way of checking the profitability of the pump system is touse Life Cycle Cost analysis. This will show not only the ”energy cost”but all costs related to the pump system.The result of the analysis can alsoshow the pay-back time of aspeed con- trolled solutioncompared to a traditional constantspeed pump.Result of Life Cycle Cost analysis

Grundfos FLOW THINKINGPrimary - Secondary Circuit With Variable SpeedSecondary PumpsLoadBalancing Valve2 – WayValveChillersPanel withPLC & VFD`sCommonPrimary PumpsSecondaryPumpsAir -Separator

Grundfos FLOW THINKINGHow Do We Achieve This Reduction In PowerConsumption ??By Using Variable Frequency Drive and Logic controllerwith the Secondary Pumps….

Grundfos FLOW THINKINGBasic Law which helps in achieving this – Affinitylaw1. Flow 2 = Flow 1 (Speed 2 / Speed 1 )2. Head 2 = Head 1 (Speed 2 / Speed 1 ) 23. BKW 2 = BKW 1 (Speed 2 / Speed 1 ) 3If Diameter of Impeller is to be trimmed then instead ofspeed the same can be used in above formulas.

Grundfos FLOW THINKINGBasic ConceptPMUSet Value4 – 20 mAFrom FieldSensor (DPT)PFUOutputToVFD/PumpPFU – Pump Functional UnitPMU – Pump Management Unit

Grundfos FLOW THINKINGOpening/Closing of 2- Way Valve-Signal from the sensor, installed at loadregulates the valve opening & closing.-This way differential across 2-way valve alsochanges & accordingly output signal is given toPLC.Temperature SensorLoadOutput to PFU from DPT

Grundfos FLOW THINKINGAn ExampleLoadBalancing ValveDPTChillersPanel with PLC &VFD`sSecondaryPumpsPrimary Pumps

Grundfos FLOW THINKINGAPPROVAL FROM INTERNATIONALAGENCIESApproval from – CE, U/LConforms to - Electromagnetic compatibility(89/336/EEC) to standard EN 50 081 – 1 and EN 50082 – 2 and Electrical equipment design 73/23/EECstandard to EN 60 204-1.

Grundfos FLOW THINKINGTertiary PumpingIn Air-conditioning Systems

Grundfos FLOW THINKINGAir conditioning systemsImproved balancing by Tertiary pumpsColling towerHeat recovery Fan coils MCooling ceilingMPressureholdingMCooling surfacePrimarypumpBuffertankChillerSecondarypumps

Grundfos FLOW THINKINGSystem with only secondary pumpsHAirunitAirunitFancoilsAirunitFancoilsMax.∆pBuffertank∆p: connection pointQ max.Q∆psecondarypumpDistance/pressure profile∆p: pipes,control valvesfan coils etc.System with tertiary pumpsAirunitAirunitFancoilsAirunitFancoilsHTertiary pumpsMM M M MBuffertankMax.∆p∆p: connection pointQ max.Q∆psecondarypump∆p:control valveDistance/pressure profile

Grundfos FLOW THINKINGHybrid SystemAirunitAirunitFancoilsAirunitFancoilsHTertiary pumpsMM M M MBuffertankMax.∆p∆p: connection pointQ max.Q∆psecondarypump∆p:control valveDistance/pressure profile

Grundfos FLOW THINKINGTertiary Systems….Few points‣ Tertiary pumps can be Variable speed…….‣ Tertiary pumps can be fixed speed also….‣ Mixing loops are not mandatory in tertiary loops…‣ But mixing loops add flexibility in the overall airconditioningsystem…‣ Tertiary pumps PLC should be controlled by DPT signal(ifvariable speed panel is used)…

Grundfos FLOW THINKINGTertiary Systems….Few points‣ For Secondary pumps only friction loss upto zonetermination point should be taken care…‣ For Tertiary pumps friction loss of valves, coil etc shouldbe taken care….

Grundfos FLOW THINKINGAdvantages with Tertiary pumps1. Smaller secondary pumps, motor and drives2. Lower differential pressure in all connection points3. Lower operation cost4. Higher flexibility if the system have to be redesigned5. Each to find the right location for the ∆p sensor6. Minimized risk of “over sizing” secondary pumps

Grundfos FLOW THINKINGMixing LoopsIn Air-conditioningSystems

Grundfos FLOW THINKINGMixing loops• Why mixing loops• Where can mixing loops be used• Different types of mixing loops• Design• Function• Energy saving by using mixing loops

Grundfos FLOW THINKINGWhy mixing loops – Increase of hydraulic balance inlarge/Tertiary/district heating or cooling systemsThe source of unbalance in a systemIn large systems the diffential pressure will decrease/increase dependinguponthe distance from the pump, and not reflect the actual need.Pressureprofile∆p ∆p ∆p ∆p∆p

Grundfos FLOW THINKINGWhy mixing loops – Increase of the control of different part of a buildingFacade dividedSystems with zonedivisionWill adapt toweather conditions:•Sun•WindFloor dividedWill adapt to use ofthe building:•Holidays•Load of the floor

Grundfos FLOW THINKINGWhy mixing loops – Correct differential temperature at the chiller returnHigh differential temperature means lower flow.Formula for calculating theflow in a cooling systemkW x 0,86Dt= m 3 /h∆t5 o C∆t5 o C∆t5 o C∆t5 o C∆t5 o C∆t5 o CIn particulary District/large cooling systems a correct differetial temperature reduces theoperation cost.

Grundfos FLOW THINKINGWhy mixing loops – parameters which influence in the indoor temperatureExternal parameter which haveinfluence on the cooling/heat demandInternal parameter which haveinfluence on the cooling/heat demandOther roomsWindSun radiationLightElectricalequipmentPeopleLightOther rooms

Grundfos FLOW THINKINGWhere can mixing loops be usedAll circulating systems where there is a demand forimproving the balance and controlling the temperatures•Heating systems•Radiator systems•Air handling units•Floor heating•District •Heating Heating/Coolingsystems•Building connection•Cooling systems•Fan coils•Air handling units•Cooling ceilingsFor Primary-Secondary as well as Secondary-Tertiary

Grundfos FLOW THINKINGMixing loops overviewSystem 1 System 2 System 3 System 4 System 5t Ot Ot Ot Ot OTertiary sideLoadt fLoadt fLoadt fLoadt fLoadtr tr trtrMMMSecondary sideMMHydraulicNO YES NO YES YESseparationTemperaturecontrolNO YES YES YES YESInvestmentMIDIUM MIDIUM HIGH HIGH HIGHOperationcost LOW LOW LOW HIGH HIGH

Grundfos FLOW THINKINGDesignSecondary sideTertiary sideOut-doortemperature sensortoThermometerLoopcontrollerTfFlowtemperature sensorShut-offvalveStrainerMCirculator pumpNon-returnvalveTrShut-offvalveControl valveReturntemperature sensor

Grundfos FLOW THINKINGFunction of the Loop controllerBy adding more or less chilled water to the tertiary side the Loop Controller isadjusting the flow temperature based on outdoor, zone supply and returntemperature.toLoopcontrollertfMtr

Grundfos FLOW THINKINGEvaluation of temperature and flow.Even the temperature on the secondary site is controlled,therewillis a large variation in the flow.Temperature evaluationFlow variationoC100%m 3 /h608050604040302020010-20600 500 400 300 200 100 0 kWHeat demandFlow temperature primary siteFlow temperature secondary siteReturn temperatureOutdoor temperature0600 500 400 300 200 100 0 kW100 83 67 50 33 17 0 %Heat demandFlow primary siteFlow secondary siteFlow by-pass

Grundfos FLOW THINKINGPumps for mixing loops single pipe systems.Primary siteThe main pumps in the primary site has toovercome the pressure drop in the control valves,heat produc-tion and the distribution net. Due to asignificant flow variation a speed controlled pumpwill be the right choice. A standby pump will supplysafety to the system.Secondary siteThe pump in the mixing loop has to overcome thepressure drop in the secondary site. Due to there isno flow variation a constant speed pump willbe the right choice.Distribution nettHeatproductionMHeatingsystemtMain pumpsMHeatingsystem

Grundfos FLOW THINKINGEnergy consumption in system with mixing loops pumps.Conclusion:1. Full hydraulic balance in the system:It will also be possible to change the cooling/heating system in one of thebuildings without disturbing the balance in in the other buildings.2. Reduced power consumption:Experiences shown a reduction of chiller power consumption when mixingloops are installed.3. Reduced pump energy consumption:Can be reduced to up to 30-40%

Grundfos FLOW THINKINGEnergy consumption in system with mixing loops pumps.Conclusion:4. Better zone control:Mixing loop will help in achieving better individual zone control.5. Smaller Secondary pumps:In case of Primary-secondary-tertiary systems smaller secondary pumps areused6. Suitable for any application:Can be used for Primary-secondary-Tertiary, Primary-Tertiary as well asPrimarysecondary

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