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Sizing
Your Swimming Pool Pumps
We
offer a complete line of swimming pool pumps and parts, from all the major
manufactures. Sta-rite, Hayward, American Products, Purex,
Pac Fab, Jacuzzi and others Whether its a single part or a complete pump
we can supply your needs.
For Information
on:
Pool Products
Swimming Pool Pumps Complete Units
Pool Pump Parts
Swimming Pool Pump Motors
Sizing Your Swimming Pool Pump
The pump consists of two principal parts: A motor and
the wet end. The motor provides the power to move the components located
in the wet end. The wet end consists of a trap, and impeller, which is
responsible for moving the water.
The
pump is probably the most important single piece of equipment
in the circulation system. Selecting
a pool pump is determined by a long list of factors. It is best to review
this list even if you are replacing an existent pump with the same size.
If you are tempted to increase the HP of the pump, you must read and understand
this.
Total
dynamic head (TDH) is the sum of the resistance experienced by water flowing
through the pipes and filter system. Each elbow, foot of pipe, fittings
and anything else that is in the circulation system increases the Total
Dynamic Head. The TDH will affect the flow rate. For a new pool this is
somewhat more easy to calculate, but for an existing pool, with piping
below the ground it is much more difficult.
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Typical
Calculation:
1.
Friction Loss (vacuum Side)
Common
Head loss factors
Vacuum (at pump) -
Assumes 2" suction pipe
not to exceed 40 feet.
Minimal fittings - One
2" valve and full rated pump.
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Total
Dynamic Head
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Horsepower
of Pump
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Feet
of water
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3/4
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4.5
- 5.5 ft of water
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1
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7.0
- 9.0 ft of water
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1-1/2
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10.0
- 12.5 ft of water
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2
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13.5
- 16 ft of water
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Let's
use a 1 HP pump to perform a calculation, Reading the table above we
have 9 feet of head.
2.
Friction loss (pressure side): _____(clean filter pressure) psig.
x 2.31 ft of head / psig. = ______ft of head (pressure side). Typically
filter pressure should be 10-15 lbs.
Using
10 feet of pressure we will have 23 ft of head on the pressure side.
3.
The Total Dynamic Head: __9_(Vacuum)__ + _23(Pressure)_
= ____32__
Practically
speaking 30-40 feet of head is a good estimate to size a pump. which
can be adjusted upward or downward depending on the circumstances.
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Pipe
characteristic (maximum Flow)
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Pipe
Size (PVC)
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Pump
Output (GPM) versus Total Resistance to Flow (feet of Head)
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Suction
Line (vacuum)
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Return
Line (pressure)
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| 1-1/2
" |
50
GPM |
65
GPM |
| 2 |
85
GPM |
105
GPM |
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pool filter, swimming pool pump part
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A
typical performance chart
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Pump
Size
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Pump
Output (GPM) versus Total Resistance to Flow (feet of Head) |
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20
ft |
30
ft |
40
ft |
50
ft |
60
ft |
70
ft |
| 1/2 |
55 |
45 |
29 |
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- |
| 3/4 |
67 |
58 |
47 |
31 |
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| 1 |
85 |
76 |
65 |
50 |
27 |
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| 1-1/2 |
97 |
90 |
80 |
67 |
50 |
10 |
| 2 |
116 |
111 |
99 |
85 |
70 |
51 |
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NOTES:
Numbers in table represent
typical information.
Consult specific information for the pump you intend
to use.
Move up to next level of resistance 32 -> 40 feet
and specify the pump that exceeds the calculated flow rate.
Select a filter based on the flow required
(always going to larger filter size).
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Filter
Capacity and Flow Rates
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DE
Filter
sq-feet |
Cart
Filter
sq-feet |
Sand
Filter
sq-feet |
Design
Flow Rate (gpm) |
Turnover
in Gallons |
| 8
hours |
10
hours |
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25 |
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25 |
12,000 |
15,000 |
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1.75 |
35 |
16,800 |
21,000 |
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2.20 |
44 |
21,200 |
26,400 |
| 24 |
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48 |
23,040 |
28,800 |
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50 |
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50 |
24,000 |
30,000 |
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2.64 |
52 |
24,960 |
31,200 |
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3.13 |
62 |
29,760 |
37,200 |
| 36 |
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72 |
34,560 |
43,200 |
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75 |
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75 |
36,000 |
45,000 |
| 48 |
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96 |
46,080 |
57,600 |
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4.91 |
98 |
47,040 |
58,800 |
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100 |
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100 |
48,000 |
60,000 |
| 60 |
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120 |
57,600 |
72,000 |
| 72 |
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120 |
57,600 |
72,000 |
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150 |
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150 |
72,000 |
90,000 |
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swimming pool pump and filter hayward swimming pool pump
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