Disposals are usually straightforward, and a fair number of Summerville calls turn out to be something you can resolve yourself in two minutes.
Try this first
If it hums but does not turn, the motor is fine and something is jammed. Cut the power, free the flywheel with the hex key that came with the unit, then press the reset button on the underside. If it is silent, the reset button alone often solves it. We will tell you this on the phone rather than charge you to press a button.
When it is genuinely finished
Water leaking from the body of the unit rather than the connections means the housing has corroded through, and that is not repairable. Persistent tripping after a reset points to a failing motor.
The Summerville connection
Disposals in newer local builds are frequently the builder-grade minimum, and they are noticeably underpowered for a household that cooks. If yours jams constantly on ordinary food waste, the unit is undersized rather than faulty.
The grease problem it causes
A disposal grinds food but does nothing about fats, which then cool and coat the drain line — and in hard water areas that coating collects scale. A large share of recurring Summerville kitchen drain clogs start at the disposal.