VRN and VRW Pressure Regulated Flow Control Valves

2. The State of the HVAC Industry Escalating energy and electrical power costs Time-of-day pricing, kW demand charges for transmission & generation Variable speed pumping standard (ASHRAE 102) Single pumps have higher head than staged systems Phased building construction Over-powered physical plant for sections completed first Can have poor control, non-warranty product failures LEED makes designers responsible for building performance Zoning most effective with hydronics Intense focus on reduced resource needs Sophisticated designs with higher capital cost Industry strapped for time/people Non-traditional hydronic geographies (e.g.: sunbelt States) Growing skills gap Untrained installers, inexperienced designers Need to mistake-proof system design and commissioning Water quality more important than ever

3. Benefits of Pressure-Independent Control Pressure-regulated valves enable: 20% up to 50% energy savings reported in industry case studies Smaller chillers and pumps Reduced capital cost Reduced energy consumption Reduced electrical demand Dynamically self-balanced loops All load conditions Smaller piping, direct connection In retrofit: increased chiller capacity in existing systems

4. Traditional Hydronic HVAC System Design Large or multiple chillers/boilers Operated inefficiently at low ?T, except at design loads Large, high flow pump stations Large supply and return risers Static balancing valves (mechanical Division) Automatic control valves (HVAC Division) 3-way valves at end of loops for pressure relief, flow maintenance

5. Modern Hydronic HVAC System Design Smaller/fewer chillers/condensing boilers Operated efficiently at high ?T under all load conditions Smaller, high pressure, variable speed pump stations Smaller supply and return risers Balancing valves integrated with Automatic control valves Pressure-independent control

6. Traditional HVAC Flow Balancing Limit flow to calculated design when every branch of the HVAC system is “wide open” Prevents closest branches from starving far loops Standard solution: multi-turn manual balancing valves Hard to achieve well-balanced system with traditional products and methodology 3 passes around the building to adjust balancing valves in each zone Specialized trade (adds cost and time to Building commissioning) Reverse-return piping materials-intensive, does not save energy Real system conditions vary as heat loads change from design conditions Traditional designs put additional capacity in place to overcome these issues, driving higher initial cost and higher operating costs

7. Characteristic curve of impeller correlates flow and pump head pressure As controls change flow, head pressure changes inversely Pressure changes travel in the system at the speed of sound At low load, small pressure changes cause large changes in thermal output, causing hunting in the control system Affinity Laws, Centrifugal Pumps: Flow is proportional to speed Pressure varies with square of speed Power varies with cube of speed Head pressure relative to flow increases at lower speeds Pump/System Interaction Issues

8. VFD vs Staged Pump Control

9. Effects of Coil Overflow Coils need low velocity, turbulent flow to transfer heat efficiently. High flow = high water velocity = low coil ?T Maximum heat output ˜ 114% >90% of Control valves are oversized* by mechanical contractors to ensure design flow met (<5% probability @ target space temperature) Oversized control valves restrict turn-down ratio = poor control @ light loads(100% probability)

10. Improving Coil Efficiency Coils are guaranteed to run at low capacity most of the year Chiller efficiency varies* by2~3% / °F differential temperature change Low flow = low water velocity = high coil ?T @ equal BTUh At low loads and high ?T, small flow variations due to head pressure changes cause disproportionate coil heat transfer changes when using conventional control valve and static balancing valves Resulting room temperature change forces control system to compensate

11. Installation Cost Analysis

12. Pressure-Regulated Control Valve Design

13. Uses high head pressure to operate a differential pressure regulator across valve seat Flow & heat affected only by control valve Matches the flow to the load in every heat transfer device, without excess flow, throughout full operating range Fast, accurate system set-up Applies at every operating point Much more than just balancing Simpler, lower-cost piping layouts Extends HVAC equipment life Improves efficiency Lowers operating cost The water-side equivalent of VAV control Benefits of Regulated Flow Control

14. Honeywell VRN and VRW Valves

15. Inside a VRN-Series Valve

16. Features of the VRW-Series

17. Pressure Regulation Accuracy

18. Easy-To-Select Part Numbering System

19. VRN2 Model Selections

20. Reference Material Resources www.specifyhoneywell.com – Includes wiring diagrams, guide specs, selection guide and other resources that are useful for Consulting Engineers. Honeywell's Take-Off Service has been trained on product line customer.honeywell.com/spectakeoff  or email takeoff.service@honeywell.com

21. Barriers to Pressure-Independent Design Old habits die hard Disbelief (“a BTU is a BTU”) Delivered BTU’s rely on system efficiencies Balancing valves not always used (= “premium” piping) No balancing valve substitution to offset cost Balancing valves fall under mechanical trade Guide specs need to make note that balancing valves not required “Flow Verification” report may still be required Measure across the coil, not valve Controls trade objects to carrying higher cost parts 2-position application alternatives: Flow limiters cheaper, effective for 0%/100% operation A pressure-regulated valve is a flow limiter at all valve positions Some designs use control valve Cv to approximate balancing Heat transfer = flow X time open X coil efficiency Reverse-return piping mitigates need to balance, pushes spend to piping from controls

22. Writing P-I System Specifications Design to max-rated chiller ?T Size piping and equipment to reduced flow rates Specify pressure-regulated control valves in Division 23 09 13.33 Formerly MasterFormat Division 15 Mechanical section to specify balancing valves not required Specify commissioning parameters for pump VFD’s High pressure cut-out required if valves can dead-head flow Audit coil flows at light loads, not just Design Specify water quality requirements in Division 23 25 13

23. Honeywell's VRN and VRW-Series' Advantages Honeywell’s full line is designed to meet complete HVAC systems needs Full range of sizes from ½" to 6" (1 gpm to 469 gpm) VRN: ½ to 3" NPT, 1~95 gpm fixed sizes VRW: 2-½ to 6" flanged, 39~469 gpm, adjustable ranges Industry-leading precision for tighter control Flow control accuracy within ± 5% Maintain tighter ?T to optimize Chiller efficiency Industrial-grade performance at HVAC prices Unique Field-Serviceable control valve Serviceability = long-term life = long-term savings Field-proven technology

24. The New Solution to Flow Control

26. Future Discussions Other State-of-the-Art Controls and Sensors for Commercial HVAC and Integrated Security

27. Energy-Saving Controls and Systems Variable Frequency Drives Demand-based (CO2) zone/central ventilation control Wireless sensors Pressure-independent VAV controllers Fan coil & unit ventilator controllers Programmable and communicating controllers and thermostats for temperature, humidity, and pressure Economizer ventilation control and free cooling Building Automation Systems WebStat Spyder Niagara Framework Boiler Outdoor reset Commercial boiler safety Commercial combustion efficiency Proportional, two-position, failsafe, and stay-in-place actuators for ventilation, fire & smoke dampers and valve control Commercial HVAC (Division 23) globe, ball, and butterfly control valves from ½ to 20" (DN15~500) Take-off Service Energy monitoring HVAC/security integration