---
title: "What Is Flow switch? Pool Glossary | Marina Pool Services"
description: "A flow switch is a sensor that confirms water is moving through a salt cell or heater. Plain-English pool glossary from Marina Pool Services in Grapevine, TX."
url: https://marinapool.multisites.ai/glossary/flow-switch
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Equipment

# Flow switch

A flow switch is a sensor that confirms water is moving through a salt cell or heater.

The flow switch protects equipment. It tells the salt cell or heater that water is moving. With no flow, the device shuts off, so the cell does not run dry or the heater does not overheat.

If your salt system shows a no-flow alert, check baskets, valves, and the filter first. If flow is good and the alert stays, the switch may be stuck or dirty. Do not bypass it. A pro can test and replace it. Heaters use a similar safety, called a [pressure switch](https://marinapool.multisites.ai/glossary/pressure-switch).

[Marina can helpSalt Water System Installation & Service](https://marinapool.multisites.ai/our-services/salt-water-system-installation)

## Related terms

-   [Salt cell](https://marinapool.multisites.ai/glossary/salt-cell)
-   [Salt chlorine generator](https://marinapool.multisites.ai/glossary/salt-chlorine-generator)
-   [Pressure switch](https://marinapool.multisites.ai/glossary/pressure-switch)
-   [Pool heater](https://marinapool.multisites.ai/glossary/pool-heater)

## 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)