Main 24 System Eco Expansion Vessel 8 Litre – Refurbished| MPN 5114691

A heating system runs at its best when every component is doing its job — and the Main 24 System Eco Expansion Vessel (MPN 5114691) is one of the most essential of them all. As water heats up and expands within your sealed central heating circuit, this vessel absorbs the excess volume, regulating pressure and temperature and preventing the kind of strain that leads to leaks, faults, and reduced system efficiency over time.

With an 8-litre capacity, it provides ample space for water expansion, keeping your system running smoothly and efficiently across every heating cycle. Compatible with most Baxi boilers, it's designed for straightforward, hassle-free installation — a reliable, precise fit that gets your system back on track from day one.

Main Expansion Vessel 8L 5114691 regulates pressure and temperature by absorbing excess water during heating.FULLY REFURBISHED AND COMES WITH 12 MONTHS WARRANTY.

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Why Choose This Product?

When it comes to a component as critical as your expansion vessel, starting fresh gives you the ultimate peace of mind. This fully refurbished Main expansion vessel comes straight from stock, untouched and ready to install, with no prior use and no refurbishment — just genuine quality from the moment it arrives. It regulates system pressure effectively, reduces the risk of leaks and faults, and supports smooth, consistent heating performance throughout your boiler's daily operation.

Backed by a full 12-month warranty, it's a dependable choice for both homeowners and professional installers who want genuine, unused quality without any compromise.

Delivery & Returns

Orders placed before 1:00 PM are dispatched the same working day, with both standard and next working day delivery options available at checkout. Returns accepted within 30 days, provided the item is unused and in its original packaging.


Note: Please confirm that MPN 5114691 matches your existing part before placing your order. Installation must always be carried out by a Gas Safe registered engineer to ensure safety compliance and warranty validity.