General Pump Pressure Washer System Installation, Operation & Service Manual page 4

ELECTRIC MOTOR HORSEPOWER REQUIRED TO DRIVE A PUMP
GPM 100 PSI 200 PSI
.5 .04 .07
1.0 .07 .14
1.5 .10 .21
2.0 .14 .28
2.5 .17 .34
3.0 .21 .42
3.5 .24 .48
4.0 .28 .56
5.0 .35 .70
6.0 .42 .84
7.0 .49 .98
8.0 .56 1.12
9.0 .62 1.24
10.0 .70 1.40
NOTES:
If you wish to direct drive your pump from an electric
motor, you may want to use a "C" face motor.
*Tip Orifice Dia.
Size (Inches)
40 PSI 100 PSI 250 PSI 500 PSI 600 PSI 700 PSI 800 PSI 1000 PSI 1200 PSI 1500 PSI 2000 PSI 2500 PSI 3000 PSI 3500 PSI 4000 PSI
2 .034 .20
4 .052 .40
4.5 .055 .45
5 .057 .50
5.5 .060 .55
6 .062 .60
6.5 .064 .65
7 .067 .70
7.5 .707
.75
8 .072
.80
8.5 .074
.85
9 .076
.90
9.5 .078
.95
10 .080
1.00
12 .087
1.20
15 .094 1.50
20 .109 2.00
30 .141 3.00
40 .156 4.00
* A commonly used standard for tip size is the "nozzle number" which is equivalent to the nozzle
capacity in GPM at 4000 PSI. Spray angle does not affect nozzle volume.
250 PSI 300 PSI 400 PSI
.09 .11 .14
.18 .21 .28
.26 .31 .41
.35 .42 .56
.43 .51 .69
.53 .63 .84
.60 .72 .96
.70 .84 1.12
.88 1.05 1.40
1.05 1.26 1.68
1.23 1.47 1.96
1.40 1.68 2.24
1.55 1.86 2.48
1.75 2.10 2.80
1, A gasoline engine should be sized 1.8 times the electric horsepower requirement.
2. Always select a motor/engine with a horsepower rating above the minimum requirements shown
above. Example: 5.0 GPM - 1250 PSI is 4.40 minimum electric horsepower requirement, use a
5 horsepower electric motor.
SPRAY TIP SELECTION CHART
OUTPUT VOLUME (GPM) AT VARIOUS PRESSURES (PSI)
.32 .50 .71 .77
.63 1.00 1.40 1.60
.71 1.10 1.50 1.70
.79 1.30 1.80 1.90
.87 1.40 1.90 2.10
.95 1.50 2.10 2.30
1.00 1.70 2.30 2.50
1.10 1.80 2.50 2.70
1.20 1.90 2.70 2.90
1.30 2.00 2.80 3.10
1.30 2.20 3.00 3.30
1.40 2.30 3.20 3.50
1.50 2.40 3.40 3.70
1.60 2.50 3.50 3.90
1.90 3.00 4.20 4.60
2.40 3.80 5.30 5.80
3.20 5.00 7.10 7.80
4.70 7.50 10.60 11.60
6.30 10.00 14.20 15.60
500 PSI 700 PSI 1000 PSI 1250 PSI 1500 PSI 2000 PSI 2500 PSI 3000 PSI 4000 PSI
.18 .26 .35
.35 .52 .70
.52 .77 1.03
.70 1.04 1.40
.86 1.29 1.72
1.05 1.56 2.10
1.20 1.80 2.40
1.40 2.08 2.80
1.75 2.60 3.50
2.10 3.12 4.20
2.45 3.64 4.90
2.80 4.16 5.60
3.10 4.65 6.18
3.50 5.20 7.00
Check with your motor supplier for technicla
information.
.80 .89 1.0
1.70 1.80 2.0
1.90 2.00 2.2
2.10 2.20 2.5
2.30 2.50 2.8
2.50 2.70 3.0
2.70 2.90 3.3
2.90 3.10 3.5
3.20 3.40 3.8
3.40 3.60 4.0
3.60 3.80 4.3
3.80 4.00 4.5
4.00 4.30 4.8
4.20 4.50 5.0
5.00 5.40 6.0
6.40 6.80 7.5
8.40 9.00 10.0
12.80 13.60 15.00 16.40
16.80 18.00 20.00 21.60
4
.44 .53 .70
.88 1.05 1.40
1.29 1.55 2.06
1.76 2.10 2.80
2.15 2.58 3.44
2.64 3.15 4.20
3.00 3.60 4.80
3.52 4.20 5.60
4.40 5.25 7.00
5.28 6.30 8.40
6.16 7.35 9.80
7.04 8.40 11.20
7.73 9.28 12.40
8.80 10.50 14.00
1.1 1.2 1.4 1.6
2.2 2.5 2.8 3.1
2.4 2.8 3.0 3.6
2.8 3.1 3.6 4.0
3.0 3.4 3.8 4.4
3.2 3.7 4.2 4.8
3.6 4.0 4.6 5.2
3.8 4.3 5.0 5.6
4.1 4.6 5.3 6.0
4.4 5.0 5.6 6.2
4.6 5.3 6.0 6.7
5.0 5.5 6.4 7.1
5.2 5.8 6.8 7.6
5.4 6.1 7.0 8.0
6.4 7.3 8.4 9.5
8.2 9.2 10.6 12.0
10.8 12.2 14.2 16.0
18.40 21.2 24.0
24.40 28.4 32.0
.88 1.10 1.40
1.76 1.92 2.80
2.58 3.09 4.12
3.53 4.20 5.60
4.30 5.14 6.88
5.28 6.30 8.40
6.00 7.20 9.60
7.04 8.40 11.20
8.80 10.50 14.00
10.56 12.60 16.50
12.32 14.70 19.60
14.08 16.80 22.40
15.56 18.58 24.80
17.60 21.00 28.00
1.7 1.9 2.0
35. 3.8 4.0
3.9 4.3 4.5
4.4 4.7 5.0
4.8 5.2 5.5
5.2 5.6 6.0
5.7 6.0 6.5
6.1 6.6 7.0
6.5 7.0 7.5
7.0 7.5 8.0
7.4 8.0 8.5
7.8 8.5 9.0
8.3 9.0 9.5
8.7 9.4 10.0
10.4 11.2 12.0
12.9 14.0 15.0
17.4 18.8 20.0
26.0 28.0 30.0
34.8 37.6 40.0