Operation and Maintenance

1
Operation and Maintenance

• Whats wrong with the pump?

2
Permit/plans

• System type, installation date
• Tankage
• Size
• Dimensions
• Gallons per inch
• Operating head
• Elevations or elevation head
• System design
• Supply line
• Manifold
• Orifice (size and number)

3
Permit/plans

• Pump specifications
• Size
• Manufacturer
• Pump delivery rate
• Dose
• Volume
• Frequency
• Control panel and float configurations

4
Information from permit
120 ft.
8 laterals
12 5/32 orifices per lateral
3 Design pressure head
3 Elevation head
1/3 hp Liberty Pump
25 ft.
IS THIS ALL THE INFORMATION THAT YOU NEED?
1000 gal pump tank
1000 gal septic tank
5
Flow rate calculation

• How many orifices?
• 8 laterals X 12 orifices
• 96 orifices

6
Flow rate calculation

• What is the flow per orifice?
• Use table
• 5/32 orifice at 3 pressure head
• 0.5 gpm per orifice

7
Flow rate calculation

• What is the total flow?
• of orifices x Flow per orifice
• 96 x 0.5 gpm
• 48 gpm

8
Field Evaluation

• Pump Delivery Rate (PDR) 48 gpm
• Tank dimensions are 4 x 8 x 4 128 ft3
• Tank volume 128 ft3 x 7.49 gal/ft3 957 gal
• Gal. per foot 4 x 8 x 1 x 7.49 gal/ft3
• 240 gal/ft
• Gal. per inch 240 gal/ft/12 per ft
• 20 gal per inch

9
Field Evaluation

• Pump run time 5 min
• Draw down 12 in
• 20 gal/in
• Total gal 12 in x 20 gal/in 240 gal
• Gal per min (Actual PDR) 240 gal / 5 min
• 48 gpm
• Design PDR 48 gpm
• Pump efficiency Actual PDR/Design PDR x 100
• 48/48 x 100 100

10
Field Evaluation Notes

• Pressure head set at 1.8
• Could not get the pressure head any higher
• Gate valve open all the way
• IS THERE A PROBLEM?
• WHAT NEXT?

11
Possible Problems

• In the field
• Broken line
• Unscrewed cap
• Loose fitting
• Other????
• Solutions???

12
Possible Problems

• The field checks out OK.
• Where to now?
• The Pump.

13
How do you know its the pump?
14
The following slides follow the SSPMA
Troubleshooting Guidelines

• The format of the Guide is
• What is the problem
• List of potential cause followed by
• Specific test to see if the cause suggested is
  the true cause
• Potential solution

15
What is the problem?

• Pump delivers an insufficient amount of effluent

16
POSSIBLE CAUSE OF PROBLEM
11. Impeller loose on shaft. 12. Clogged or
damaged impeller. 17. Water inflow excessive. 18.
Clogged screen or pump inlet. 19. Air locked or
air bound pump. 20. Air bleed hole blocked. 21.
Pipe discharge closed by obstruction or ice. 22.
Inadequate discharge pipe diameter. 23.
Defective or inoperative check valve. 24. Check
valve installed in wrong direction. 30. Loose
shaft coupling. 32. Too high a static and
friction head. 33. Motor running backwards. 38.
Sump bottom soft and muddy. 39. Improperly sized
pump.
17
To simplify

• There is a problem with the pump operation
• Clogged
• Worn
• etc.
• There is a problem with the supply line
• Blockage
• The pump is sized wrong
• Too small
• Too much head loss

18
TEST(S)

• H. Remove pump, disconnect power, connect to
  rated voltage and actuate control switch.
• J. Disconnect power, remove pump from sump and
  observe for freedom of impeller and shaft
  rotation.
• N. Measure vertical portion of discharge pipe
  (over 15 feet is excessive). If discharge pipe
  length is extremely long, the friction losses may
  exceed pump capacity. Observe number of pipe
  fittings and reducing bushings.
• 0. Evacuate sump.
• P. Examine and observe.
• S. Observe source and amount of water inrush.
• U. Observe arrow on check valve indicating
  direction of flow.
• V. Check gate of check valve.
• W. Remove screen and observe condition.
• X. Measure discharge pipe and compare with
  manufacturers suggested diameter (should be no
  smaller than pump discharge).

19
To simplify

• Check the pipe parts
• Valves
• Air release or anti-siphon hole
• Check the pump parts
• Inlet
• Impeller
• Etc.
• Check the tank
• Check pump size

20
CORRECTION

• 9. Clean volute and impeller and remove any
  blockage.
• 12. Have larger sump and pump installed.
• 14. Clean screen.
• 15. Have installed larger diameter discharge
  piping.
• 16. Have larger pump installed.
• 17. Remove any reducing pipe fittings and elbows.
• 18. Clean or snake discharge line.
• 20. Drill 1/8 or 3/16 air bleed hole between
  pump discharge and check valve.
• 21. Clean out air bleed hole.
• 23. Tighten fasteners, replace key.
• 25. Clean gate of check valve.
• 30. Clean sump.
• 31. Return pump to Authorized Service Center.

21
To simplify

• Replace worn/broken parts
• Remove blockages
• Add air release hole
• Replace pump with a new pump

22
How do you know what pump to use?

• Use the pump curve to size pump

23
Total Head

• Total head (elevation head pressure head
  friction head)
• Elevation head difference from pump to end of
  manifold
• Pressure head operating head (2 to 5 ft)
• Friction head loss of pressure due to friction
  in pipe and fittings as a function of flow (must
  know flow rate)

24
Elevation Head
4
Elevation Head (H)
25
Friction Head (Pipe)
e
b
c
a
d
Supply pipe length a b c d e
26
Friction loss pipe fittings
27
Friction Head (Fittings)

• Pump and supply line
• 1 ball valve (2) 1.3
• 1 union (2) 2
• 1 check valve (2) 19
• 3 90 elbows (2) 3 x 7 21
• (in field) 1 90 elbows (2) 7
• 1 gate valve (2) 1.3
• (in field) 1 Tee (2) 10
• Total 51.6

28
Friction Head (must know flow rate)

• F F(pipe) F(fittings)
• 2 schd 40 PVC 4.58 per 100 _at_ 48 gpm
• or
• 0.0458 per 1
• 25 supply line
• 51.6 of 2 equivalent for fittings
• 25 51.6 76.6 of 2 PVC
• F 76.6 x 0.0458 3.51

29
Friction Head Alternative Method

• Supply Line length 20
• 25 supply line
• 2 schd 40 PVC 4.58 per 100 _at_ 48 gpm
• or
• 0.0458 per 1
• 25 (0.2)25
• 25 5 30
• F 30 x 0.0458 1.37

30
Total Head

• T H P F
• T 4 3 3.51 10.51
• Or
• T 4 3 1.37 8.37

31
Pump Selection

• Use pump curve
• Plot Flow vs Total Head
• Should lie below curve in middle 1/3 for pump to
  be OK

32
Pump Curve
33
Pump Curve
Total Head 10.51
Flow Rate 48 gpm
34
Pump Curve
Total Head 8.37
Flow Rate 48 gpm
35
Total Head 10.51
Flow Rate 48 gpm
36
Total Head 8.37
Flow Rate 48 gpm
37
Do you inform the Health Department before
replacing the pump?

• YES!