1. Preferred Utilities Manufacturing Corp.
Top 20!
Things to Watch Out For…
Preferred Utilities Mfg. Corp.
31-35 South St. • Danbury • CT

2. Tank Heating and Insulation
No. 20
Tank Heating and Insulation

3. 20 - Tank Heating and Insulation
Aboveground Storage Tank (AST) – installed in a cold climate – # 2 thru # 6 oil, heating requirements and insulation of tank
Emergency generators – Approximately 40 F is the cloud point of paraffin wax in # 2 fuel oil Thermopump System application
Option for Thermopump System is a winter blend of fuel oil
Piping - # 6 oil – heat trace the pipe and insulate or FOS, FOR, steam and condensate return lines in a single carrier pipe with insulation

4. 20 - Tank Heating and Insulation

5. Tank Gauge Installation
No. 19
Tank Gauge Installation

6. 19 - Tank Gauge Installation
TG-EL-WF, Wire Float Assembly requires 14” of clearance for installation
TG-EL-WF offers mechanical testing of the assembly without removal from the tank
Vaulted tanks have minimal overhead space

7. 19 - Tank Gauge Installation

8. No. 18
Fuel Leak Detection

9. 18 - Fuel Leak Detection
Underground Storage Tank (UST) – Pipe leak detection requirements, pitch double wall pipe containment to the piping sump on the tank
Underground Storage Tank (UST) – Typical pipe pitch is 1/8”/ft, long linear runs could present problems, might require a second sump
All tanks –Discriminating leak detector for the Dry Interstitial space of the tank

10. 18 - Fuel Leak Detection

11. Tank Overfill Prevention
No. 17
Tank Overfill Prevention

12. 17 - Tank Overfill Prevention
Tank gauging with overfill alarm station
Type 2 In-Wall Spill Container with Overfill Alarm Station
Mechanical fill line overfill prevention device (i.e. OPW type 61)
Vent line with overfill alarm switch

13. 17 - Tank Overfill Prevention

14. Multiple Day Tank Applications
No. 16
Flow Control

15. 16 – Flow Control Multiple Day Tank Applications
Install control flow components: Three valve by-pass arrangement for manual operation and servicing, (2) Solenoid valves, N.C. (normal fill) & N.O. Solenoid valves (overfill prevention)
Options: Fuel filter, flow switch

16. 16 – Flow Control

17. Multiple Day Tank Applications
No. 15
Overflow Port Size

18. 15 - Overflow Port Size Day Tank continuous overflow system
                                                   
Day Tank continuous overflow system
Verify single day tank overflow port size capable to overflow pump supply capacity
Overflow port location & high level switch on the level controller
Redundant back up – Install vent line leak switch & utilize N.O. Solenoid valves for vent line overflow conditions

19. No. 14
Day Tank Location

20. 14 - Day Tank Location
Day tank above main storage tank – gravity return, overflow port sized to meet pump flow rate
Day tank below main storage tank – non-gravity return, return pump system is required, pump flow rate capacity larger than pump set supply system

21. No. 13
Air Entrainment

22. 13 - Air Entrainment
BPRV: Riser piping, install BPRV at the bottom of the riser, set pressure to maintain a constant head to prevent the cascading of the fuel and entraining air
Syphon Breaker: Day tank header system applications, can use in conjunction with the BPRV

23. 13 - Air Entrainment VENT VACUUM BREAKER (OPTIONAL) TRAP HEADER RETURN
SUPPLY
SUPPLY
SUPPLY
ENGINE #1
ENGINE #2
ENGINE #3
RELIEF
IN OUT
PUMP SET

24. 13 - Air Entrainment
                                                   
Separate the Fuel Oil Supply (FOS) and Fuel Oil Return (FOR) Piping drop tubes in the tank to prevent the recycling of air
FOS, 6-8” off the bottom of the tank
FOR, 18-20” off the bottom of the tank, add a 90 elbow to direct return fuel away from suction

25. No. 12
Burner & Day Tank Loops

26. 12 – Burner & Day Tank Loops
Burner – Flooded Loop
Review piping losses & layout, BPRV may be required to divert oil into day tank
Day tank supply at end of loop to assure burners will have sufficient fuel supply
Burner – Pressure Loop
Connect day tank FOS downstream of the BPRV

27. No. 11
Fire Safety

28. 11 - Fire safety
Lever Gate Valve: Install with a fusible link in the FOS piping to the pump set
Fusomatic valve: Install in FOS lines to the fuel consuming equipment (i.e. burners and generators)

29. No. 10
Relief Valves

30. 10 - Relief Valves
Relief valves on pump set– piped into the return line with no shut off valves
Multiple tank system with ball/gate valve arrangement, pipe relief valve into pump suction, utilize pump flow switch for safety shutdown

31. Fuel Oil Return Shut-off Valves
No. 9
Fuel Oil Return Shut-off Valves

32. 9 - FOR Shut-off valves No shut-off valves in the FOR piping
If multiple tank design recommend utilizing a Tank Selector Valve, preventing a positive shutoff in the return line
If tank selector valve not desirable, recommend automatic ball valves with end switches: preventing a positive shutoff with proper alignment and preventing a tank overfill due to improper valve alignment

33. Vent Line Vertical Height
No. 8
Vent Line Vertical Height

34. 8 - Vent Line Vertical Height
Main Storage Tanks and Day Tanks
Maximum - 12’ of vertical vent line
Important - 5 psi rating on standard tanks
2.31 ft = 1 psi
12”/2.31=5.19 psi

35. Foot Valve Installation
No. 7
Foot Valve Installation

36. 7 - Foot Valve Installation
Install foot valve to prevent loss of prime if top of the tank is below the centerline of the pump
Utilize an extractor fitting for easy removal of foot valve
Extractor fitting can be a potential air leak

37. No. 6
Maximum Height for ASV

38. 6 - Maximum Height for ASV
Install Anti-Syphon Valve (ASV) if top of the tank is above the centerline of the pump
Maximum height for ASV – 20’ above centerline of pump
Above 20’ utilize a solenoid valve for an anti-syphon device

39. No. 5
Maximum Elevation

40. 5 - Maximum Elevation Bottom of tank to pump centerline: 15 feet
Rule of Thumb: # 2 oil, 15’=11.5” hg static lift
Allows for line & fitting losses
Allows for pump wear and dirty strainer
Allows for the unforeseeable design issues

41. No. 4
Long Linear Runs

42. 4 - Long Linear Runs
Minimize linear pipe runs, Ideally design system for a maximum 15” hg at pump inlet (empty tank), utilize your “Preferred Utilities Pipe Sizing Program” tool!!!
Continuously exceed 17” of vacuum will cause premature pump wear & failure
Long pipe runs present priming challenges
Avoid inverted loop FOS pipe runs

43. No. 2
Fuel Oil Filtration

44. 3 – Fuel Oil Filtration
NFPA 110 Standard for Emergency and Standby Power Systems 2002 Edition
, Tanks shall be sized so that the fuel is (1) consumed within the storage life, or (2) provision shall be made to re-place stale fuel or (3) clean fuel.

45. 3 – Fuel Oil Filtration
Future NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, 1999 Edition
8-6.4, Fuel Supply Maintenance. The fuel storage tanks shall be kept as full as possible at all times, but never less than 50 percent of tank capacity. The tanks shall always be filled by means that will ensure removal of all water and foreign material.

46. 3 – Fuel Oil Filtration
Solution: Preferred Filtration Sets

47. No. 2
Flow Rate Sizing

48. 2 - Flow Rate Sizing Fuel Oil Loop, Burners – Flooded Loop
Series – burners with integrated pumps
Burner return line piped into the FOS of the next burner
Pump flow rate based on burn rate of the burners in the beginning of the loop plus the pump rate of the last burner, pump set flow 1.5 times the total consumption.
Small burners require an Operating Safety Valve (OSV), NFPA code requirement (i.e. Power Flame, Webster, Gordon Piatt).

49. 2 - Flow Rate Sizing

50. 2 - Flow Rate Sizing Fuel Oil Loop, Burners – Pressure Loop
Parallel – burners without integrated pumps
Burner return line piped into the FOR piping down stream of the back pressure regulating valve
Pump flow rate based on burn rate and fuel oil bypass, rule of thumb is 1.5 to 2 times the total burn rate of all burners
Back Pressure Regulating Valve (BPRV)

51. 2 - Flow Rate Sizing

52. 2 - Flow Rate Sizing Day Tank Fuel Oil Supply Loop
Emergency Generators FOR returning to day tank, size pump set to meet total burn rate
Emergency Generators FOR returning to main tank, size pump set to meet injector pump capacities
Determining factor for FOR to day tank vs. main tank: fuel oil cooling radiator to prevent day tank overheating
Determine duty cycle of pump set

53. System Design & Integration
No. 1
System Design & Integration

54. 1 – System Design & Integration
Work with your Preferred Utilities Regional Managers
Educate your customers and consulting engineers of the benefits of having a Preferred Utilities system at their facility
Integrate the system to offer sole source responsibility. This is to assure the customer the highest standards of product quality and system integrity for reliability
Write the specification for the engineer!!!

55. Preferred Utilities Manufacturing Corp
For further information, contact...
Preferred Utilities Manufacturing Corporation
31-35 South St. • Danbury • CT
T: (203) • F: (203)