hot tub pumps - general info

 The pump is the hardest working piece of equipment on your spa.

The pump wet end must be filled with water in order to create a vacuum, resulting in the pump pulling the water out of the spa. The pump housing will remain full of water while the pump is on, and will remain full or partially full of water when the pump is shut off. When you turn on the pump, the motor will begin to rotate.

The motor rotation spins the pump impeller, located inside the pump’s wet end. The impeller uses a water tight mechanical seal to stop water from leaking out between the electric motor shaft and the impeller

It is very common practice in the Hot Tub industry to label a motor with a higher H.P. rating than it actually operates at. This practice is called “up-rating “. The reason behind this is obvious, the perception from the public is that the higher the H.P. the more water that is delivered to the jets. This is a patently false concept as the following examples illustrate.

PUMP MODEL / H.P. Rating / Flow Rate at 15 P.S.I.
Waterway high-flo / 4 hp / 142 gpm.
Jacuzzi Piranha / 4 hp / 164 gpm.
Waterway super-flo / 4.5 hp / 182 gpm
Waterway executive / 3 hp / 230 gpm

To check the real H.P. of a motor, ignore the label and do the following calculation:

Voltage X Amperage = Watts
Where 746 watts = 1 H.P.

Example

Motor A 230 volts X 12 amps = 2760 watts / 746 = 3.7 H.P.

Motor B 230 volts X 8.4 amps = 1932 watts / 746 =2.59 H.P.

Educating ourselves that water delivery is larger than just H.P. rating is key to explaining plumbing engineering and massage benefits.