---
title: "What Is Union fitting? Pool Glossary | Marina Pool Services"
description: "A union fitting is a threaded joint in pool plumbing that you can unscrew so equipment can be removed for service."
url: https://marinapool.multisites.ai/glossary/union-fitting
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Equipment

# Union fitting

A union fitting is a threaded joint in pool plumbing that you can unscrew so equipment can be removed for service.

Unions sit on both sides of the pump, filter, and heater. They let a technician pull a part without cutting pipe. Without unions, a simple pump swap becomes a plumbing job.

Signs of trouble: a drip at the nut, cracked threads, or a nut that looks bleached by sun. A small leak at a union can pull air into the pump and cause noise and poor flow. Tighten by hand only, because over-tightening cracks plastic. If a union keeps leaking, the O-ring or the fitting needs replacing.

[Marina can helpPool Equipment Repair & Service](https://marinapool.multisites.ai/our-services/pool-equipment-repair)

## Related terms

-   [Pool plumbing](https://marinapool.multisites.ai/glossary/pool-plumbing)
-   [Pump basket](https://marinapool.multisites.ai/glossary/pump-basket)
-   [Air leak](https://marinapool.multisites.ai/glossary/air-leak)

## 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)