PUMPS

1 . A pump comprising:

a. a wet end body defining (i) a liquid inlet and (ii) a liquid outlet;

b. a rotatable motor shaft; and

c. a fan comprising:

i. a central opening configured to receive the rotatable motor shaft;

ii. a front;

iii. a rear;

iv. an outer periphery;

v. a first plurality of blades extending from the rear;

vi. a second plurality of blades extending from the front; and

vii. a plurality of pass-through holes from the rear to the front.

2 . A pump according to claim 1 in which each blade of the first plurality of blades defines a first end adjacent the central opening and a second end adjacent the outer periphery.

3 . A pump according to claim 2 in which each blade of the second plurality of blades defines a first end adjacent the central opening and a second end adjacent the outer periphery.

4 . A pump according to claim 3 in which each blade of the first plurality of blades has a first depth and each blade of the second plurality of blades has a depth less than the first depth.

5 . A pump according to claim 1 further comprising a fan assembly comprising:

a. a cover having a non-solid face; and

b. an interior in which the fan is positioned.

6 . A pump according to claim 5 in which the interior is configured such that air entering it through the cover exits both (a) through the plurality of pass-through holes of the fan and (b) around the outer periphery of the fan.

7 . A pump according to claim 5 further comprising a base and in which the cover is removable so as to expose the interior without needing access, from a bottom side of a motor of which the rotatable motor shaft is a part, to any fasteners.

8 . A pump according to claim 5 further comprising a screw (a) received by the cover and (b) forming part of a ground bonding lug.

9 . A pump according to claim 1 further comprising a plurality of stages positioned within the wet end body, each of the plurality of stages including a diffuser and an impeller.

10 . A pump according to claim 1 further comprising a handle integrated into the wet end body.

11 . A pump comprising:

a. a wet end body defining (i) a liquid inlet and (ii) a liquid outlet;

b. a motor shaft defining an axis; and

c. a plurality of stages positioned within the wet end body, each of the plurality of stages comprising an impeller and a diffuser, with each impeller being configured to rotate about the axis.

12 . A pump according to claim 11 in which each of the plurality of stages defines a module separately removable from the wet end body.

13 . A pump according to claim 12 in which (a) each diffuser comprises two parts configured to be connected together and (b) the impeller is fitted between the two parts as connected together.

14 . A pump according to claim 13 further comprising a fan comprising:

a. a central opening configured to receive the motor shaft;

b. a front;

c. a rear;

d. an outer periphery;

e. a first plurality of blades extending from the rear;

f. a second plurality of blades extending from the front; and

g. a plurality of pass-through holes from the rear to the front.

15 . A pump according to claim 11 further comprising a handle integrated into the wet end body.

16 . A booster pump for a pressure-side automatic swimming pool cleaner comprising:

a. a wet end body defining (i) a liquid inlet and (ii) a liquid outlet configured to supply pressurized water to the automatic swimming pool cleaner;

b. a rotatable motor shaft defining an axis;

c. a fan comprising:

i. a central opening configured to receive the rotatable motor shaft;

ii. a front;

iii. a rear;

iv. an outer periphery;

v. a first plurality of blades (A) extending from the rear;

vi. a second plurality of blades extending from the front; and

vii. a plurality of pass-through holes from the rear to the front;

d. a fan assembly comprising:

i. a cover having a non-solid face; and

ii. an interior (A) in which the fan is positioned and (B) configured such that air entering it through the cover exits both (1) through the plurality of pass-through holes of the fan and (2) around the outer periphery of the fan; and

e. a plurality of stages positioned within the wet end body, each of the plurality of stages:

i. defining a module being separately removable from the wet end body; and

ii. comprising (A) an impeller and (B) a two-part diffuser, with each impeller (1) configured to rotate about the axis and (2) fitted between parts of the two-part diffuser.