---
title: "What Is Freeze sensor? Pool Glossary | Marina Pool Services"
description: "A freeze sensor is a sensor that reads air temperature for freeze protection. Plain-English pool glossary from Marina Pool Services in Grapevine, TX."
url: https://marinapool.multisites.ai/glossary/freeze-sensor
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Equipment

# Freeze sensor

A freeze sensor is a sensor that reads air temperature for freeze protection.

A freeze sensor tells your system when it is cold enough to act. It reads the air temperature and signals the control to start the pump or heater.

The sensor should sit outside, shaded, and in open air, not tucked in a hot box. A bad or misplaced sensor can fail to trigger in a freeze or can run the pump all season. Test it before winter. If it does not work, ask a pro to check it. See [freeze guard](https://marinapool.multisites.ai/glossary/freeze-guard) for the full setup.

[Marina can helpFreeze Guard & Winterization](https://marinapool.multisites.ai/our-services/freeze-guard)

## Related terms

-   [Freeze guard](https://marinapool.multisites.ai/glossary/freeze-guard)
-   [Pool automation](https://marinapool.multisites.ai/glossary/pool-automation)
-   [Control panel](https://marinapool.multisites.ai/glossary/control-panel)
-   [Thermostat](https://marinapool.multisites.ai/glossary/thermostat)

## 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)