---
product_id: 4811297
title: "Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2\" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi"
brand: "watts"
price: "₨70011"
currency: LKR
in_stock: false
reviews_count: 13
url: https://www.desertcart.lk/products/4811297-watts-etx-30-non-potable-water-carbon-steel-expansion-tank
store_origin: LK
region: Sri Lanka
---

# 1/2" MNPT connection Max pressure 75 psi 4.7 gal tank volume Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi

**Brand:** watts
**Price:** ₨70011
**Availability:** ❌ Out of Stock

## Summary

> 🔥 Keep your heating system cool under pressure with Watts ETX-30! ⚙️

## Quick Answers

- **What is this?** Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi by watts
- **How much does it cost?** ₨70011 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.lk](https://www.desertcart.lk/products/4811297-watts-etx-30-non-potable-water-carbon-steel-expansion-tank)

## Best For

- watts enthusiasts

## Why This Product

- Trusted watts brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Effortless Installation:** Standard 1/2" MNPT connection and tire valve charging port for quick, hassle-free setup.
- • **Robust Carbon Steel Build:** Epoxy-coated for corrosion resistance and long-lasting durability in demanding environments.
- • **Pre-Charged for Performance:** Comes ready at 12 psi to maintain optimal system pressure and prevent overpressure events.
- • **Generous 4.7 Gallon Capacity:** Handles thermal expansion with ease, reducing system stress and downtime.
- • **Trusted Watts Quality Since 1874:** Engineered for reliability in both commercial and residential hydronic heating systems.

## Overview

The Watts ETX-30 is a 4.7-gallon carbon steel expansion tank designed for closed loop hydronic heating systems. Featuring a durable epoxy finish and a 1/2" MNPT connection, it is pre-charged at 12 psi and rated for a maximum pressure of 75 psi. This tank efficiently manages thermal expansion, protects system components, and ensures long-term heating system reliability in both residential and commercial settings.

## Description

Product Description The Watts Non-Potable Water Expansion Tank, with a generous 4.5-gallon volume, is expertly designed for use in both commercial and residential closed loop hydronic heating systems. Its primary function is to control the thermal expansion of hot water, ensuring that system pressure remains below the relief setting of the relief valve and preventing overpressure situations.Constructed from high-quality carbon steel with a durable epoxy finish, this expansion tank is built to last. The tank features an expansion membrane that effectively minimizes the loss of the air charge, guaranteeing a long and trouble-free operational life for the entire heating system.The design of this water expansion tank allows for straightforward installation, as it mounts directly to the supply piping. It includes a 1/2" MNPT system connection and a 0.302-32" charging valve connection, which is a standard tire valve, facilitating easy on-site charging and maintenance.Pre-charged at 12 psi, this expansion tank is ready for immediate integration. With a maximum pressure rating of 60 psi, the Watts Non-Potable Water Expansion Tank is capable of handling significant pressure fluctuations. It works seamlessly in conjunction with hot water heaters to absorb increased water volume, thus preventing system overpressure. This feature not only ensures the safety of the system but also enhances its efficiency and longevity. Whether in a residential or commercial setting, this expansion tank provides a reliable solution for managing the thermal expansion of non-potable water in closed loop hydronic heating systems. From the Manufacturer Use the Watts series ETX water expansion tank in tandem with your hot water heater to absorb increased water volume resulting from hot water boiler heating and keep system pressure below the relief setting. Use in closed-loop, non potable water heating systems. Durable steel tank with 60 psi maximum working pressure.

Review: Perfect Fit and Replacement. Watts is what you need!! - Perfect Fit and replacement. Purchased the EXT-30 to replace my failed Flextrol expansion tank purchased 12/2020. Apparently the bladder failed, causing my hydronic heating system to increase pressure causing the pressure pop off valve to drip. The old tank was small, 2.1 gallon size. When researching replacements, I accidently ordered the 4.5 gallon. Thankfully it just barely fit. I have three zones and fingers crossed the larger capacity will endure less stress during the repeating thermo cycling. Watts tank is well built, came pre charged at 12 psi. Spun right on 1/2 mnpt connection. Ordered on Monday, delivered Wednesday and 30 minutes later was installed. Pressures have maintained, no leaks, and zero worries. Btw, I called the plumbing supply store where I purchased the Flextrol in 2020, I believe it was less than 100 bucks, wanted a whopping $150.
Review: Better pricing - Easy to install. Better pricing than from the Big Box store. Good quality.

## Features

- WATER EXPANSION TANK: With a generous 4.5 tank gallon volume, the Watts Non-Potable Water Expansion Tank is designed for use in commercial and residential closed loop hydronic heating system piping to control the thermal expansion of hot water and maintain system pressure below the relief setting of the relief valve.
- DURABLE CONSTRUCTION: This tank is constructed from high-quality carbon steel with an epoxy finish, ensuring long-lasting performance. It is also equipped with a durable expansion membrane that minimizes the loss of the air charge.
- VERSATILE MOUNTING: This tank is designed for easy installation, mounting directly to the supply piping. It features a 1/2" MNPT system connection and a 0.302-32" charging valve connection (standard tire valve) to facilitate on-site charging.
- HIGH PRESSURE CAPACITY: Pre-charged at 12 psi, this expansion tank is built to withstand the demands of hydronic heating systems, boasting a maximum pressure rating of 60 psi. It works in tandem with hot water heaters to absorb increased water volume, preventing system overpressure and ensuring the longevity and efficiency of the heating system.
- EVERY DROP COUNTS: Water. It's in our name and close to our hearts. Since 1874, Watts Water Technologies has been delivering innovative technologies that make the world's most precious resource safe and accessible. Everything we design is made to keep the Earth's most precious resource safer, cleaner, and more useful for our customers. Our family of brands offers one of the most varied product lines in the world, with world-class, water-related solutions.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0086DDNEI |
| Date First Available | August 17, 2005 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 8 pounds |
| Item model number | ETX-30 |
| Manufacturer | Watts |
| Product Dimensions | 10.8 x 11.1 x 14.8 inches |

## Product Details

- **Brand:** Watts
- **Product Dimensions:** 10.5"W x 14.8"H
- **Color:** Gray
- **Wattage:** 30 watts
- **Style:** Non-Potable

## Images

![Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi - Image 1](https://m.media-amazon.com/images/I/21OkKRNrqpL.jpg)
![Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi - Image 2](https://m.media-amazon.com/images/I/31EvqfcfBsL.jpg)
![Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi - Image 3](https://m.media-amazon.com/images/I/31MI68yvVJL.jpg)
![Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi - Image 4](https://m.media-amazon.com/images/I/31S8jZxm45L.jpg)
![Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi - Image 5](https://m.media-amazon.com/images/I/31WYLV4N1nL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Perfect Fit and Replacement. Watts is what you need!!
*by W**** on March 8, 2025*

Perfect Fit and replacement. Purchased the EXT-30 to replace my failed Flextrol expansion tank purchased 12/2020. Apparently the bladder failed, causing my hydronic heating system to increase pressure causing the pressure pop off valve to drip. The old tank was small, 2.1 gallon size. When researching replacements, I accidently ordered the 4.5 gallon. Thankfully it just barely fit. I have three zones and fingers crossed the larger capacity will endure less stress during the repeating thermo cycling. Watts tank is well built, came pre charged at 12 psi. Spun right on 1/2 mnpt connection. Ordered on Monday, delivered Wednesday and 30 minutes later was installed. Pressures have maintained, no leaks, and zero worries. Btw, I called the plumbing supply store where I purchased the Flextrol in 2020, I believe it was less than 100 bucks, wanted a whopping $150.

### ⭐⭐⭐⭐⭐ Better pricing
*by P***N on August 14, 2025*

Easy to install. Better pricing than from the Big Box store. Good quality.

### ⭐⭐⭐⭐⭐ Worked Just Fine!
*by K***T on December 20, 2025*

OEM. Worked Just Fine!

## Frequently Bought Together

- Watts ETX-30 Non-Potable Water Carbon Steel Expansion Tank for Closed Loop Hydronic Heating System Piping, 1/2" MNPT Connection, Tank Volume 4.7 Gallons, Maximum Pressure 75 psi
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*Product available on Desertcart Sri Lanka*
*Store origin: LK*
*Last updated: 2026-02-22*