1	Submersible Pump Basics Horsepower (HP) GPM rating Pump curves Voltage Wire sizing
2	What is One Horsepower ? One horse power is the power to lift 33,000 pounds one foot in one minute One HP is the power to lift 3962 gallons one foot in one minute One HP is the power to lift 10 gallons 396 feet in one minute
3	One Horsepower & Pump 1 HP lifts 10 gallons 396 feet in one minute 50 PSI = 116 ft (115.5) 1 HP pump lifts 10 gallons 396 feet (280’ + 50 psi) in one minute Theoretically, a 1 HP pump provides 10 gpm @ 50 psi from a depth of 280’
4	One Horsepower & Pump Theoretically, a 1 HP pump provides 10 gpm @ 50 psi from a depth of 280’ Theoretically, a 1 HP pump provides 20 gpm @ 50 psi from a depth of 82’ Theoretically, a 1 HP pump provides 5 gpm @ 50 psi from a depth of 676’
5	Pump Efficiency ? Theoretically, a 1 HP pump provides 10 gpm @ 50 psi from a depth of 280’ In reality, a 1 HP pump with a 10 gpm rating provides 4.6 gpm @ 50 psi from a depth of 280’ or 10 gpm @ 50 psi from a depth of 170’
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8	The Pump Curve TDH is lift + pressure(psi) GPM is delivery rate 8G is delivery rating Most efficient @ 7 gpm GPM / impellers HP is power rating
9	Why the Wrong Pump Is Installed Buy same pump as the pump in their neighbor’s well Replace old pump with same size even if going from a jet pump to a submersible Don’t know how Takes a little time and effort Don’t understand the consequences Bigger pump costs more = more profit
10	Effects of the Wrong Pump Up-thrust creates impeller-bearing wear Cavitation creates impeller wear Bigger is not always better Pump runs dry Thermal overload Customer is not happy!!! Installers may lose money and customers
11	$$$ Benefits of the Proper Pump Avoid call-backs Save money on purchase price Save monthly on power consumption Avoid service calls and warranty problems Longer lasting pump when operating at the correct side of the curve Retain satisfied customers Word-of-mouth advertising
12	The Formula Calculate the GPM required Measure and record Calculate you findings: TDH = L + F + P Choose correct pump from the “Family Curve” chart Typically, installers match the pump to well yield
13	TDH = L + F + P L = Total vertical Lift from pumping level in the well to the point of delivery, in feet. F = Total of Friction losses, expressed as head in feet. P = Pounds pressure needed to operate the system, converted into feet of head.
14	Step 1 Determine the GPM A. Rule of Thumb: The “Rule of Thumb” is a simple method that can be used to determine the consumption requirements of a water system. Simply count the fixtures and water outlets in the home. This total number of fixtures should equal the approximate GPM required.
15	Example: Kitchen Sink 1 Dishwasher 1 Bathrooms Sink 1 Tub/Shower 1 Toilet 1 Laundry Washing Machine 1 Utility Sink 1 Outside Hydrants 3 Total Fixtures and Outlets 10
16	B. “Seven-Minute-Peak Demand” The Water Systems Council selected seven minutes as the peak period of time because this is the average time of higher water usage for such devices as a shower or automatic washer
17	B. “Seven-Minute-Peak Demand” When – Most families have a peak demand for water early in the morning when everyone first gets up or in the evening. How – Use Table 1 to determine the peak demand. Read down the column in the table under the number of bathrooms in the house to the Normal seven minute peak demand total.
18	B. “Seven-Minute-Peak Demand”
19	C. “Match to Well Yield” This is not an exact science!!! Obtain well yield and depth from driller If yield is 10 gpm or higher, use 10 gpm pump If yield is 3 gpm or less, use 5 gpm pump If yield is 3 - 10 gpm, use 7 gpm pump or 10 gpm pump, depending on depth
20	D. “Put In a 10 GPM Pump” Know your pump curve! Know depth of well and yield Can pump be placed 20’ off bottom and not over-pump well? See depth-yield chart If well is deep and has decent yield, can we go up in power and not over-pump well?
21	TDH = L + F + P L = Total vertical Lift from pumping level in the well to the point of delivery, in feet. F = Total of Friction losses, expressed as head in feet. P = Pounds pressure needed to operate the system, converted into feet of head.
22	Step 2 – Measure and Record 1^st – Static Water Level 2^nd – Draw Down 3^rd – Pumping Lift (Static Level + Draw Down = Pumping Lift) 4^th – Elevation Lift
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24	TDH = 155’ + F + P L = Total vertical Lift from pumping level in the well to the point of delivery, in feet. F = Total of Friction losses, expressed as head in feet. P = Pounds pressure needed to operate the system, converted into feet of head.
25	Calculating Friction Loss To calculate the frictions loss multiply the horizontal run by the friction loss per 100 then divide your findings by 100. 2. Multiply the drop pipe length by the friction loss, then divide that answer by 100. Note: To find the friction loss per 100, go to your reference book. Remember, to check the friction loss, you will need to know: Pipe size Type of pipe that will be used The gallons-per-minute (GPM) required
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27	Step 2 – Measure and Record (cont.) 5^th – Pump Setting 6^th – Length of Horizontal Run 7^th – Fittings used to connect system
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29	Calculating Friction Loss To calculate the friction loss for the fittings to be used, look up the number of equivalent feet of straight pipe in your reference book. Add these lengths together and multiply by the friction loss, then divide by 100.
30	Calculating Friction Loss (cont.) Horizontal Run (60’ X friction loss 6.88 per 100’)/100 = 4.13’ or 5’ Drop pipe length (180’ X friction loss 6.88 per 100’)/100 = 12.38’ or 13’ 1”Fittings equivalent length in feet (29’ X friction loss 6.88 per 100’)/100 = 2’ Total Friction Loss = 20’ Note: Always round up fractions of feet when calculating friction loss.
31	TDH = 155’ + 20’ + P L = Total vertical Lift from pumping level in the well to the point of delivery, in feet. F = Total of Friction losses, expressed as head in feet. P = Pounds pressure needed to operate the system, converted into feet of head.
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33	System Pressure Multiply the PSI (the average switch setting) by 2.31. This will convert service pressure to feet. 50 psi × 2.31 = 115.5 or 116’
34	TDH = 155’ + 20’ + 116’ L = Total vertical Lift from pumping level in the well to the point of delivery, in feet. 155’ F = Total of Friction losses, expressed as head in feet. 20’ P = Pounds pressure needed to operate the system, converted into feet of head. 116’
35	System Requirements 10 gpm @ 291’ TDH
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37	Pump Shroud Shroud is installed over submersible pump 4” wellseal is placed just above pump to hold 4” PVC casing Pump inlet is located mid-length of shroud Casing prevents pump intake from directly contacting sidewall of well
38	How a Pump Shroud Works Pump inlet is located mid-length of shroud Water flows past outside of shroud at high velocity High speed rock particles continue to fall Water flowing upward inside shroud cools motor
39	A Hot Motor is Not Cool Heat is the enemy Causes of heat Incorrect voltage Starting surge - cycling Poor water flow A cool motor lasts longer - it can run continuously
40	A Shroud Keeps Your Motor Cool In water up to 86º F, flow past motor should be at least .25 ft/sec .25 ft/sec past a 4” motor in a 6” well requires 13 gpm .25 ft/sec past a 4” motor in a 4” shroud requires 1.2 gpm
41	"John Nykamp" John Nykamp, R.S. Environmental Health Program Specialist Guilford County Public Health Department 400 W. Market St Greensboro, N.C. 27401 (336)641-4807 (336)641-7613 FAX (336)641-3730 jnykamp@co.guilford.nc.us Well Contractor Certification Commissioner http://www.ncwelldriller.org/