---
product_id: 418519981
title: "Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray"
brand: "watts"
price: "€ 439.57"
currency: EUR
in_stock: false
reviews_count: 5
category: "Watts"
url: https://www.desertcart.gr/products/418519981-watts-etx-30-non-potable-water-expansion-tank-1-2
store_origin: GR
region: Greece
---

# 1/2 in MNPT connection 4.5 gal capacity Pre-charged 12 psi, max 60 psi Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray

**Brand:** watts
**Price:** € 439.57
**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 Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray by watts
- **How much does it cost?** € 439.57 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.gr](https://www.desertcart.gr/products/418519981-watts-etx-30-non-potable-water-expansion-tank-1-2)

## 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

- • **Versatile Compatibility:** Perfect for residential and commercial hydronic heating systems, supporting up to 150,000 BTU output.
- • **Robust 4.5 Gallon Capacity:** Handles thermal expansion with ease, reducing system stress and extending lifespan.
- • **Precision 1/2 inch MNPT Connection:** Ensures a secure, leak-free fit for seamless integration into your hydronic system.
- • **Pre-Charged for Instant Performance:** Comes pre-pressurized at 12 psi, so you’re ready to install and go—no extra setup needed.
- • **Durable Carbon Steel with Epoxy Finish:** Built to resist corrosion and maintain integrity under high temperatures up to 240°F.

## Overview

The Watts ETX-30 is a 4.5-gallon non-potable water expansion tank designed for closed loop hydronic heating systems. Featuring a durable carbon steel body with epoxy finish and a pre-charged 12 psi diaphragm, it effectively manages thermal expansion and maintains system pressure below relief valve settings. With a 1/2 inch MNPT connection and compatibility for residential and commercial use, it supports heating outputs up to 150,000 BTU, ensuring long-lasting, worry-free performance.

## Description

Non-potable water expansion tanks are 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. The pre-pressurized steel tank features durable expansion membrane that prevents contact of the water with the air in the tank. This rugged diaphragm minimizes loss of the air change and ensures long and trouble-free life for the system. Model ETX mounts to supply piping. Maximum Pressure 75psi 5.3 bar for ETX. 4.7 gallon For closed loop hydronic piping system 1/2 inches male pipe thread Used on closed loop hydronic system piping to control thermal expansion of hot water Accepts increased volume of eater created when the system water is heated Steel construction Rugged flexible diaphragm Compact size Compatible with gylcol systems Hydrostatic test pressure 75 PSI Maximum temperature 240 fahrenheit Maximum pressure 60 PSI Pre-charged at 12 PSI For use on finned tube baseboard from 25,000 BTU to 150,000 BTU, Convectors unit heaters from 75,000 BTU to up to 100,000 BTU, Cast iron radiators from 50,000 BTU to 100,000 BTU cast iron baseboards up to 50,000 BTU net boiler output.

Review: juste ce qui me falais
Review: 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.

## Features

- This non-portable water expansion tank is for closed loop hydronic heating system piping to control the thermal expansion of hot water and maintain system pressure below the relief sett of the relief valve
- The carbon steel tank is pre-charged at 12 psi, has a 4.5 gallon volume, and features a durable expansion membrane preventing minimizes loss of the air change and ensures long and trouble-free life for the system
- Made of carbon steel with epoxy finish, mounts to supply piping, with 1/2 inch MNPT system connection and .302-32 inch charging valve connection for on-site charging of the tank
- Maximum pressure 60 psi and can be used in residential or commercial hydronic heating systems
- Use in tandem with your hot water heater to absorb increased water volume ensuring long and trouble-free life for the system

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0086DDNEI |
| Batteries required | No |
| Customer Reviews | 4.6 4.6 out of 5 stars (562) |
| Date First Available | 5 May 2013 |
| Included components | Expansion Tank |
| Is assembly required | No |
| Item Weight | 3.63 kg |
| Item diameter | 0.75 Inches |
| Item model number | ETX-30 |

## 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 Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray - Image 1](https://m.media-amazon.com/images/I/51mEF4g1JWL.jpg)
![Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray - Image 2](https://m.media-amazon.com/images/I/616HsGeSnOL.jpg)
![Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray - Image 3](https://m.media-amazon.com/images/I/61Chl3Np7GL.jpg)
![Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray - Image 4](https://m.media-amazon.com/images/I/61Hn7DxE-wL.jpg)
![Watts ETX-30 Non-Potable Water Expansion Tank 1/2 in MNPT Connection, 4.5 gallon, Gray - Image 5](https://m.media-amazon.com/images/I/61I+1a2dY-L.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by B***E on 19 February 2024*

juste ce qui me falais

### ⭐⭐⭐⭐⭐ Review
*by W**** on 8 March 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.

### ⭐⭐⭐⭐⭐ Review
*by K***S on 23 December 2023*

Worked perfectly.

## 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
- Taco 400-4 1/8-Inch-NPT Float Air Hy-Vent
- Watts 0342691 30 PSI Pressure Relief Valve, Bronze, 3/4" 335 M2-030

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*Product available on Desertcart Greece*
*Store origin: GR*
*Last updated: 2026-03-03*