Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units

1. Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units Presented by Bruce Standerwick

2. Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units Part 1: The Importance of ESP on Gas-Fired Units

3. Two Cases When Actual ESP not Equal to Design ESP • Case A: Actual ESP > Design ESP • Case B: Actual ESP < Design ESP

4. Design Point 2.1” TSP –“W.C. 4,100 cfm CFM in 1000’s

5. Actual Operation: Case A 2.6” 2.1” TSP –“W.C. 3,780 cfm 4,100 cfm CFM in 1000’s

6. Case A: Actual ESP > Design ESP • Solutions: • Adjust sheave if possible • Change sheave and possibly belts

7. Actual Operation: Case A 3.0 BHP 2.6” 2.1” 2.6 BHP TSP –“W.C. 3,780 cfm 4,100 cfm CFM in 1000’s

8. Case A: Actual ESP >Design ESP • Solutions: • Adjust sheave if possible • Change sheave and possibly belts • Need (1), (2) and possibly larger motor size with new motor controls -- Will motor fit?

9. Motor Compartment of DFC

10. Case A: Actual ESP > Design ESP • Solutions: • Adjust sheave if possible • Change sheave and possibly belts • Need (1), (2) and possibly larger motor size with new motor controls -- Will motor fit? • Shaft deflection may require larger shaft and bearings

11. Fan Assembly Under Construction

12. Motor Compartment of DFC

13. Operating Point New Operating Point Design Point TSP –“W.C. 3,900 cfm CFM in 1000’s

14. Fan Assembly Under Construction This dimension is smaller on a fan with a narrow housing

15. Case A: Actual ESP > Design ESP • Solutions: • Need sheave change • Need (1) and larger motor and controls • Need (1), (2) and possibly larger motor size with new motor controls -- Will motor fit? • Shaft deflection may require larger shaft and bearings • Different fan because new cfm/TSP point is not in operating range of fan in unit

16. Actual Operation: Case B 2.1” 1.6” TSP –“W.C. 4,550 cfm CFM in 1000’s 4,100 cfm

17. Case B: Actual ESP < Design ESP • Solutions: • Adjust sheave if possible • Change sheave and possibly belts

18. When Actual ESP is Different From Design ESP • Conclusions: • It’s easier to slow a fan down than to speed it up • It’s safer to overestimate the ESP than to underestimate it!

19. Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units Part 2: The Importance of Gas Pressure for Gas-Fired Units

20. Typical Gas-Fired Pipe Train in Piping Compartment

21. Typical Direct Gas-Fired Pipe Train Main Gas Pressure Regulator Main Gas Valve Auxiliary Gas Valve Maxitrol Modulating Gas Valve Gas manifold; start of factory furnished and piped components Pilot Main Gas Shutoff Valve Test Port Test Port Test Port Pilot Gas Shutoff Valve Pilot Gas Pressure Regulator Pilot Gas Valve Orificed Needle Valve

22. Direct Gas-Fired Burner in Burner Compartment

23. Direct Gas-Fired Burner at Full Fire

24. Typical Direct Gas-Fired Heater RatingPlate Max. Gas Inlet Pressure Min. Gas Inlet Pressure

25. Two Cases Where Actual Gas Pressure not Equal to Design Gas Pressure • Case A: Actual Gas Pressure > Design Gas pressure • Case B: Actual Gas Pressure < Design Gas pressure

26. Case A: Actual Gas Pressure > Design Gas Pressure Main Gas Pressure Regulator Main Gas Valve Auxiliary Gas Valve Maxitrol Modulating Gas Valve ¾” I.P.S. gas manifold; 5 psig actual gas pressure instead of 10-14” w.c. per design Pilot Main Gas Shutoff Valve Test Port Test Port Test Port Pilot Gas Shutoff Valve Pilot Gas Pressure Regulator Pilot Gas Valve Orificed Needle Valve

27. Solution for Case A:Actual Gas Pressure > Design Gas Pressure • Install a High Gas Pressure Regulator

28. Case B: Actual Gas Pressure < Design Gas Pressure Main Gas Pressure Regulator Main Gas Valve Auxiliary Gas Valve Maxitrol Modulating Gas Valve 2” I.P.S. manifold; 10” w.c. gas pressure instead of 1-2 psig per design Pilot Main Gas Shutoff Valve Test Port Test Port Test Port Pilot Gas Shutoff Valve Pilot Gas Pressure Regulator Pilot Gas Valve Orificed Needle Valve

29. Case B: Actual Gas Pressure < Design Gas Pressure • Solutions: • Add section to burner • Modify sheet metal in burner section

30. When Actual Gas Pressure is Different From Design Gas Pressure • Conclusions: • It’s much easier in the field to add a high gas pressure regulator than to rebuild a gas train/burner • It’s safer to underestimate the gas pressure than to overestimate it!

31. Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units Part 3: The Importance of Voltage on Gas-Fired Units

32. Motor Compartment of DFC

33. Components That Could be Affected by a Voltage Change • Disconnect Switch and/or Distribution Block • Fuses and Fuse Blocks • Circuit Breaker • Transformers • Starter and Overload Contactors • Motor(s) • Wiring and conduit to motor(s) • Wiring diagram

34. Relationship Between Volts and Amps • HP is proportional to volts times amps • If : HP1 = HP2 then: (volts x amps)1 = (volts x amps)2 or (volts1/volts2) = (amps2/amps1) • Amps are inversely proportional to volts at constant horsepower.

35. Two Cases Where Actual Voltage not Equal to Design Voltage • Case A: Actual Voltage > Design Voltage • Case B: Actual Voltage < Design Voltage

36. Case A: Actual Voltage > Design Voltage

37. Case B: Actual Voltage < Design Voltage

38. When Actual Voltage is Different From Design Voltage • Conclusions: • Fewer components are likely to need changing if the voltage goes up (amps go down) rather than if the voltage going down (amps go up) • It’s safer to underestimate the voltage than to overestimate it! • Wiring diagram, specification sheet and rating plate must be replaced if the voltage changes

39. Importance of ESP, Gas Pressure, and Voltage for Gas-Fired Units The End Thank You!