Viessmann Vitodens 100 WB1C Expansion Vessel 8L – Refurbished | Part No. 7837231

A healthy expansion vessel is essential to keeping your Viessmann boiler running at the correct pressure. When the diaphragm fails or the vessel loses pre-charge, every expansion cycle forces the pressure relief valve to activate — putting stress on seals, pipework and the heat exchanger. The Viessmann Expansion Vessel 8L (Part No. 7837231) is the correct replacement designed specifically for the Vitodens 100 WB1C range, restoring stable pressure control and protecting your system from recurring pressure-related faults.

This is a professionally refurbished genuine Viessmann component. Each unit is stripped, cleaned, and pressure-tested to OEM specifications before dispatch — delivering manufacturer-grade performance at a significantly reduced cost. The 8-litre capacity fits directly without modification, allowing a straightforward, compliant installation.

Compatible Viessmann Models

OEM Quality. Proven Performance. Backed by Warranty.

Every refurbished vessel is inspected and pressure-tested to OEM standards before dispatch. This unit stabilises system pressure, prevents overpressure events, and reduces long-term wear. Supplied with a full 12-month warranty — a smart, cost-effective alternative to purchasing new.

Delivery & Returns

Orders placed before 3:00 PM are dispatched the same working day. Standard and next working day delivery options are available at checkout. Returns accepted within 30 days, provided the item is unused and in its original condition.

Note: Please confirm that part number 7837231 matches your existing vessel before placing your order. Installation must be carried out by a Gas Safe registered engineer to ensure safety compliance and warranty validity.