---
title: "What Is Capacitor? Pool Glossary | Marina Pool Services"
description: "A capacitor is a part that helps a pump motor start, and a weak one causes humming and no start."
url: https://marinapool.multisites.ai/glossary/capacitor
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Equipment

# Capacitor

A capacitor is a part that helps a pump motor start, and a weak one causes humming and no start.

A capacitor stores a small electrical charge to help the motor start turning. When it weakens, the pump hums but does not spin, or it starts slowly.

Heat shortens capacitor life, so North Texas summers wear them out. Even after power is off, a capacitor can hold a charge and shock you. Do not open the motor end yourself. A pro can test the capacitor and swap it safely. A quick fix is cheaper than a burned [motor](https://marinapool.multisites.ai/glossary/pump-motor). Do not keep trying to start a pump that only hums.

[Marina can helpPool Pump Repair & Installation](https://marinapool.multisites.ai/our-services/pool-pump-repair)

## Related terms

-   [Pump motor](https://marinapool.multisites.ai/glossary/pump-motor)
-   [Motor bearings](https://marinapool.multisites.ai/glossary/motor-bearings)
-   [Pool pump](https://marinapool.multisites.ai/glossary/pool-pump)
-   [Pool timer](https://marinapool.multisites.ai/glossary/pool-timer)

## Need a hand with your pool?

Call or text and tell us what your pool needs. Estimates are free for qualifying services, and same-day estimates are possible when the schedule allows.

[Call (817) 896-1120](tel:+1-817-896-1120)[Get a quote](https://marinapool.multisites.ai/contact)

![A pool technician working on an equipment pad](https://marinapool.multisites.ai/_astro/technician-equipment-pad.BW5xZMNY_Zum1K5.webp)