---
product_id: 68236095
title: "18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055"
brand: "aquasystems"
price: "A$330"
currency: AUD
in_stock: true
reviews_count: 8
category: "Aquasystems"
url: https://www.desertcart.com.au/products/68236095-18-litre-aquasystems-arb18-potable-expansion-vessel-3-bar-integrated
store_origin: AU
region: Australia
---

# WRAS approved 18L capacity integrated bracket 18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055

**Brand:** aquasystems
**Price:** A$330
**Availability:** ✅ In Stock

## Summary

> 💦 Elevate Your Water Storage Game!

## Quick Answers

- **What is this?** 18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055 by aquasystems
- **How much does it cost?** A$330 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.au](https://www.desertcart.com.au/products/68236095-18-litre-aquasystems-arb18-potable-expansion-vessel-3-bar-integrated)

## Best For

- aquasystems enthusiasts

## Why This Product

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

## Key Features

- • **Durable Design:** Replaceable EPDM membrane for long-lasting use.
- • **Certified Quality:** WRAS approved for peace of mind.
- • **Maximize Your Space:** Integrated wall bracket for easy installation.
- • **Reliable Performance:** 18-litre capacity ensures ample potable water supply.
- • **Effortless Maintenance:** No batteries required, hassle-free operation.

## Overview

The 18 Litre Aquasystems ARB18 Potable Expansion Vessel is designed for efficient water storage, featuring a robust integrated wall bracket, a replaceable EPDM membrane, and WRAS approval, ensuring both quality and convenience for your potable water needs.

## Description

18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055 The Aquasystems ARB Potable Expansion Vessels are manufactured to comply with UK water regulations and are tested and certified by WRAS. The vessels are supplied with a replaceable membrane and feature an integrated wall bracket. They come complete with wall bracket accessories as pictured. The main purpose of the vessel is to compensate for the increase in volume of water due to the varying water temperatures in the system, e.g. Water being heated from 0°C - 100°C will increase by approx 4.5%. Features: * Aquasystems potable water expansion vessel * Vessel incorporates an integrated wall bracket * Comes with wall bracket accessories as pictured * White Epoxy coated steel container * Replaceable EPDM membrane * Pre-Charge: 3 Bar * Maximum Pressure: 10.0 * Test Pressure: 10.0 * Temperature Range: -10°C - 100°C * Suitable for Fluid Group 2 * WRAS Approved Specification: * Capacity: 18 Litre * Pre-Charge: 3 Bar * Maximum Pressure: 10.0 * Test Pressure: 10.0 * Temperature Range: -10°C - 100°C * Suitable for Fluid Group 2

Review: Good. As Described - As described. worked as expected no issues
Review: Fits Perfect - My current Baxi boiler system needed topping up on a daily basis so bought the ARB18 Expansion Vessel (Baxi Megaflow system) Package Content : 1x ARB18 Expansion Vessel (Baxi Megaflow system) Fittings The item arrvied sooner than expected, kudos to the seller. It was a like to like expansion vessel. Initially I thought the image on the product listing has like an oem - non label and non branded product. When it arrived it had all the labels as on the already fitted ARB18 Expansion Vessel (Baxi Megaflow system) . The existing ARB18 Expansion Vessel (Baxi Megaflow system) was installed in 2003 and the registered engineer said the reason I have to keep topping up the system on a daily basis was due to the expansion vessel. The installation was very simple, the engineer powered off the mains of the boiler and replaced the vessel and restarted the system and it was all good. Definitely recommed the seller and of course the ARB18 Expansion Vessel (Baxi Megaflow system) if you are looking for one. I really hope you found my review helpful and would love for you to click on the “YES” button to say so. If you don't think my review has been helpful, before you click on the “NO“ button to say I was unhelpful, I would love you to leave me a comment with your thoughts, so I can try improving my future reviews.

## Features

- Potable Water Expansion Vessel
- 18 Litre Capacity
- Integrated Wall Bracket
- Replaceable EPDM membrane
- WRAS Approved

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | Reliance Water Controls |
| Part Number | XVES050055 |
| Manufacturer reference | XVES050055 |
| Colour | White |
| Item Package Quantity | 1 |
| Batteries included? | No |
| Batteries Required? | No |

## Images

![18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055 - Image 1](https://m.media-amazon.com/images/I/41LT+nkA5NL.jpg)
![18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055 - Image 2](https://m.media-amazon.com/images/I/81SJxHb8J9L.jpg)

## Questions & Answers

**Q: Hi what size is the flexi pipe fitting . Am I correct in sayin 3/4 inch. Thanks very much**
A: Good Morning, 
The fitting is indeed 3/4 on this vessel.

**Q: Need replacement for aquasystem arb18 [m/f date april 2014] that came with gledhill unvented. will it fit the existing bracket?**
A: This should fit a small wall bracket as per the original one that was provided & installed originally.
This is a direct replacement. The B of ARB18 designates its the bracket fitting.

**Q: Hi is this vessel pre charged to 3 bar. Many thanks.**
A: Good Morning, 
Yes I can confirm this vessel is pre-charged to 3 bar

**Q: What are the dimensions of this item?**
A: H x 465mm - D x 280mm

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good. As Described
*by C***. on 27 July 2023*

As described. worked as expected no issues

### ⭐⭐⭐⭐⭐ Fits Perfect
*by A***N on 11 May 2020*

My current Baxi boiler system needed topping up on a daily basis so bought the ARB18 Expansion Vessel (Baxi Megaflow system) Package Content : 1x ARB18 Expansion Vessel (Baxi Megaflow system) Fittings The item arrvied sooner than expected, kudos to the seller. It was a like to like expansion vessel. Initially I thought the image on the product listing has like an oem - non label and non branded product. When it arrived it had all the labels as on the already fitted ARB18 Expansion Vessel (Baxi Megaflow system) . The existing ARB18 Expansion Vessel (Baxi Megaflow system) was installed in 2003 and the registered engineer said the reason I have to keep topping up the system on a daily basis was due to the expansion vessel. The installation was very simple, the engineer powered off the mains of the boiler and replaced the vessel and restarted the system and it was all good. Definitely recommed the seller and of course the ARB18 Expansion Vessel (Baxi Megaflow system) if you are looking for one. I really hope you found my review helpful and would love for you to click on the “YES” button to say so. If you don't think my review has been helpful, before you click on the “NO“ button to say I was unhelpful, I would love you to leave me a comment with your thoughts, so I can try improving my future reviews.

### ⭐⭐⭐⭐ Poor instructions and slightly misleading description
*by K***E on 2 February 2023*

The instructions are quite difficult to read, the text us ridiculously small and also don't cover much. I'm interested in how to service this and I don't feel the instructions really support me. Also when I purchased the description said "The vessels are supplied with a replaceable membrane" , I assumed this meant an extra/spare membrane for the service......which it doesn't.

## Frequently Bought Together

- 18 Litre Aquasystems ARB18 Potable Expansion Vessel 3 Bar with Integrated Bracket - XVES050055
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*Product available on Desertcart Australia*
*Store origin: AU*
*Last updated: 2026-03-08*