Selecting the right pump for your Hot Tub
Because most hot tubs use the jet pump as the main pump that moves water through the heater to increase the spa water temperature, it is common for a pump to start showing signs of wear and tear after several years of operation.
Sometimes, finding the correct pump replacement can be as simple as calling the spa manufacturer and asking for the replacement pump part number, or locating the pump part number on the pump itself, then searching online for that replacement.
However, in many cases, especially for older spas, the spa manufacturer may not be in business any longer, or the pump manufacturer has discontinued the spa’s specific pump or made changes to the pump so that it can be used across many makes and models. When this happens, you can reference your spa pump’s specifications to find the correct replacement pump.
A few things to note when searching for a pump replacement:
1. A spa pump is made up of a motor and a wet-end (the wet-end is often what is called, the “pump”)
2. Often the “part number” that you see on your spa pump is actually the motor part number only. If you want a complete replacement pump, you will need to confirm you choose the pump with the correct or most closely matching wet-end, and a motor with closely matching specifications.
3. HP (horsepower)is not an industry-standard measurement. Due to this, over the years, parts manufacturers have embellished HP. When searching for a replacement pump, you do not need to search for a pump matching HP, as the true match for your pump’s power and specs will be amperage.
What you will see on a pump/motor label when searching for a matching replacement:
Again, do not worry about HP (Horsepower), as that is not the true measurement of pump specs.
Do not search for a replacement pump by the motor model or part number, as there are many pumps with vastly different wet ends, that use the same motor.
After you have confirmed the pump motor specifications, you will need to determine your wet-end style and size.
When choosing the correct hot tub pump or wet-end replacement, in addition to knowing the specifications such as Horsepower, Amperage, Speeds, Voltage and Frame Size, you will need to confirm your pump wet-end style and the connection sizes of the intake and pressure side.
There are two primary orientations you will generally encounter, either the more standard side discharge, where the discharge is off-center from the intake, or center discharge, where the pressure side is centered with the intake side.
Side Discharge
Center Discharge
You will also need to confirm the wet-end connection sizes to make sure that it fits correctly with your pump union plumbing connections.
The most common sizes are 1.5”, 2”, and 2.5”
To determine the size of your wet-end connection (also called buttress), measure the outside diameter (OD).
If the OD measures closest to 2-3/8”, then the wet end connections are 1.5”
If the OD measures closest to 3”, then the wet-end connections are 2”
If the OD measures closest to 3-5/8”, then the wet-end connections are 2.5″
*Please note that some pumps have different-sized connections for the suction and pressure side of the wet end, so it is a good idea to confirm both connections.
Take note of the style of wet-end your pump has. Often there are other labels, part numbers, or stickers on the pump motor or wet-end indicating the manufacturer of wet-end used.
Look for Manufacturer names like:
A. Aqua Flo
B. Balboa
C. Dura-Jet
D. Jacuzzi
E. LX
F. Sta-Rite
G. Theramax
H. Waterway
I. Ultima
J. Ultimax
These manufacturer names, among others, can help in determining the correct wet-end style for your replacement pump.
Many manufacturers also included other labels on the complete pump that show the part number of the motor/wet-end combination. This part number can very often be referenced for finding an adequate replacement pump.
Some examples of these part numbers are:
For Aqua Flo:
For Balboa/DuraJet
For LX:
For Waterway:
