1. Hydronic Loop Performance: Design vs. Installed Why design and modeling data don’t always match a building’s actual performance David Kandel New Mexico Association of Energy Engineers May 26, 2015

2. Agenda Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority (Static vs Dynamic Balancing) Coil Performance Potential Solutions

3. Valve Specs Design / Modeling Assumptions Proper Valve Sizing Stable System Pressures Perfect Valve Authority

4. Valve / Coil Performance Coil Performance Coil Power / Flow Flow / Control Signal ΔTΔT BTUh Valve GPM Resulting Coil Output ΔTΔT

5. Agenda Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority Coil Performance Potential Solutions

6. Hydronic Valve Sizing Example: Coil Requires 250 GPM Design DP for valve, 4 psi DP of Valve not to exceed 5 psi

7. Hydronic Valve Sizing Example: Coil Requires 250 GPM Design DP for valve, 4 psi DP of Valve not to exceed 5 psi

8. Hydronic Valve Sizing Checking DP Example: Coil Requires 250 GPM Design DP for valve, 4 psi DP of Valve not to exceed 5 psi

9. Hydronic Valve Sizing Checking DP

10. Piping Options Coil Balance Valve Control Valve Coil Control Valve Coil Flow Limiting Valve Control Valve

11. No Balancing Device Oversized Control Valves Coil Control Valve Coil Control Valve Near Pump: High ΔP causes massive overflow ΔP 35 psi ΔP 8 psi Far From Pump: Oversized Valve cause overflow No Protection from pressure changes

12. Traditional Balancing Valve Oversized Control Valves Near Pump: Major Valve Authority issues No Protection from pressure changes Balance Valve Balance Valve Far From Pump: Minor Valve Authority issues No Protection from pressure changes Coil Control Valve Coil Control Valve ΔP 35 psi ΔP 10 psi

13. Flow Limiting Valve Oversized Control Valves Near Pump: Major Valve Authority issues No Protection from pressure changes below full flow Far From Pump: Minor Valve Authority issues No Protection from pressure changes below full flow Coil Control Valve Coil Control Valve ΔP 35 psi ΔP 10 psi Flow Limiting Valve Flow Limiting Valve

14. Agenda Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority Coil Performance Potential Solutions

15. 15 Valve Authority Coil Balance Valve

16. Static Balancing Full Flow Near Pump: High Branch Differential High Pressure Drop on Balancing Valve Balance Valve Balance Valve Far From Pump: Low Branch Differential Low Pressure Drop on Balancing Valve Coil Control Valve Coil Control Valve ΔP 20 psi ΔP 10 psi 4 PSI 2 PSI 4 PSI 12 PSI 100%

17. Static Balancing Manual Balancing Valves 100% flow No pressure drop 100% flow 12 psi pressure drop

18. 20% flow ? psi pressure drop Static Balancing Manual Balancing Valves

19. Limit the maximum coil flow… What happens below max flow? Static Balancing Automatic Balancing Valves Control Valve + Automatic Balancing valve = PI Valve

20. Static Balancing Less than Full Flow Near Pump: Massive overflow Balance Valve Balance Valve Far From Pump: Small overflow Coil Control Valve Coil Control Valve ΔP 20 psi ΔP 10 psi 5 PSI < 4 PSI 1 PSI 14 PSI < 4 PSI 2 PSI 20%

21. Static Balancing with Reverse Return Piping

22. Static Balancing Reverse Return - Full Flow Near Pump: Low Branch Differential Low Pressure Drop on Balancing Valve Balance Valve Balance Valve Far From Pump: Low Branch Differential Low Pressure Drop on Balancing Valve Coil Control Valve Coil Control Valve ΔP 10 psi ΔP 10 psi 4 PSI 2 PSI 4 PSI 2 PSI 100%

23. Static Balancing Reverse Return - Less than Full Flow Near Pump: Potential for Small Overflow Balance Valve Balance Valve Far From Pump: Potential for Small Overflow Coil Control Valve Coil Control Valve ΔP 10 psi ΔP 10 psi 5 PSI < 4 PSI 1 PSI 5 PSI < 4 PSI 1 PSI 20%

24. Dynamic Balancing

25. Dynamic Balancing All Flows Near Pump: Exact GPM Far From Pump: Exact GPM Coil PI Valve Coil PI Valve ΔP 20 psi ΔP 10 psi 0 to 100%

26. Agenda Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority Coil Performance Potential Solutions

27. Valve / Coil Performance Coil Performance Coil Power / Flow Flow / Control Signal ΔTΔT BTUh Valve GPM Resulting Coil Output ΔTΔT

28. Low Delta T at the Coil Power Output: Operating in the Waste Zone 1.Pumping more Water 2.Reduced Delta T 3.No additional BTUs Operating in the Waste Zone 1.Pumping more Water 2.Reduced Delta T 3.No additional BTUs

29. Low Delta T at the Coil

30. Coil Degradation Heat Transfer of Coil Degrades Over Time Damage to coil or fins Air-side fouling Water-side fouling

31. Coil Degradation Coil Performance Coil Power / Flow Flow / Control Signal ΔTΔT BTUh Valve GPM Resulting Coil Output ΔTΔT

32. Coil Performance Coil Degradation Waste Zone Coil Power / Flow Flow / Control Signal ΔTΔT

33. Cost of Overflowing the Coil

34. 55 gpm 320 kBTU/hr 325 kBTU/hr 65 gpm 1 2

35. Cost of Overflowing the Coil 12 BTUh320,000325,0001.6% GPM55 GPM65 GPM18% Pump hpHp increase = (65/55) 3 65% 12Δ BTUh320,000325,0001.6% GPM55 GPM65 GPM18%

36. Agenda Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority Coil Performance Potential Solutions Pressure Independent Valves Delta T Limiting

37. Pressure Independent Valves Better Performance No Issues with oversizing Perfect Valve Authority Stable control, part load and full load

38. Pressure Independent Valves PI Valve Technologies Mechanical RegulatorFlow Meter

39. Pressure Independent Technology Mechanical Regulator PuPu PdPd PdPd

40. PuPu PdPd PdPd

41. Pressure Independent Technology Electronic Pressure Independence Real Time Flow Measurement Unrestricted Flow Pattern

42. Advantages of Electronic PI Valves DP Reset Strategy DP reset can now be employed with Pressure Independence

43. Advantages of Electronic PI Valves DP Reset Strategy At Design “Critical Zone” valve full open at 5 psi Coil ePIV Coil ePIV 100% 5 PSI 100% Open 9 PSI

44. Advantages of Electronic PI Valves DP Reset Strategy At High Demand “Critical Zone” valve full open at 5 psi Coil ePIV 45% 5 PSI At Reduced Demand “Critical Zone” valve driven open, as pump reduced as far as possible. 40% 50% Open 8 PSI

45. 65% Open 80% Open 90% Open 8 PSI Advantages of Electronic PI Valves VFD Reset Strategy At High Demand “Critical Zone” valve full open at 5 psi Coil ePIV 45% 5 PSI At Reduced Demand “Critical Zone” valve driven open, as pump reduced as far as possible. 4 PSI 3 PSI 2 PSI 40%35%30% 7 PSI 6 PSI

46. Pressure Independent Technology Delta T Limiting

48. Delta T Limiting Case Study: Large Tech Company in North Carolina Position Control 240 GPM 144 GPM 96 GPM Pressure Independent P.I.+DT Management

49. Hydronic Loop Performance: Design vs. Installed Design and Modeling Assumptions & Coil Behavior Performance Problems Valve Sizing Valve Authority Coil Performance Potential Solutions Pressure Independent Valves Delta T Limiting Questions? david.kandel@us.belimo.com