For submersible well pumps there are two main parts to the pump, the pump motor and the pump end. The pump motor will be the bottom section of the pump, and the pump end will attach to the top, with the motor spinning the pumping mechanism in the pump end and pushing the water. Usually when you get a new well pump, the pump motor and pump end will often come as a package. But how do you size a pump motor to a pump end if you already have one or the other?
All pump ends will have a certain horsepower motor that they are designed to be paired with. It is oftentimes included in the name or model number of the pump end itself. For example, with our pump ends, the last two numbers refer to the horsepower motor they are meant to be paired with. The 10RPS30 is one of our pump ends, it is a 10GPM pump end, denoted by the 10RPS, designed to fit on a 3HP motor, denoted by the 30. The 40RPS15 is a 40GPM pump end, denoted by the 40RPS, designed for a 1.5HP motor, denoted by the 15. Not all companies have this exact naming convention, but you will often see a number in the product name or number that corresponds to the HP motor it was made to fit with. If you were to mismatch the pump end with a different motor, it can cause some issues. If you were to put a pump end made for a 1HP onto a 5HP motor the output of the pump would not be any higher than what it would be capable of if it were on a 1HP motor. The motor would also draw more power than one with a pump end designed for its horsepower. If you put a 5HP pump end onto a 1HP motor, then the pump would not perform nearly as well as it is designed to. The motor would also draw more power than it is rated for and will overheat, shortening its lifespan. It is also possible that it would immediately burn the pump out causing it to fail completely. It is very important to match the pump end to the correct motor, you will get a longer lasting and more efficient pump. This doesn’t mean that you cannot mix and match a pump motor to a pump end from another company, as long as the horsepower matches the pump end it should work, as most of the industry uses the same kind of connection between pump end and pump motor. You can replace just the motor of your pump if the motor burns out but the pump end is still in good shape.
Hopefully this explanation helps you find the correct motor or pump end that you need in order to get your well pump up and running. If you are unsure of the naming convention on your pump motor or end, a good way to check is to just google the part number. It will often bring up a spec sheet or a product page for the part you have, and you should be able to figure out what kind of horsepower motor or pump end you will need to get in order to get your water pumping again. You can always give us a call and ask us any questions you may have regarding getting sized for the right part you need.