Find out the model number and look on the net for info....or look up
variable speed drive well pump........

variable speed drives are more efficient but they are also more prone
to break downs and when they do go down they are more expensive to
repair than a single speed motor or pump.

Cant say much without much to go on but the above.

Like I said...take the manufacturer and model number and do some
research....ask about warranty etc......

some decent info for you

http://www.franklin-electric.com/aid/vol21no1.htm

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