The Glow-worm 0020038257 Expansion Vessel is a genuine hot water (DHW) expansion vessel designed to maintain stable pressure within the domestic hot water circuit of compatible Glow-worm boilers. As water heats and expands, the vessel absorbs excess pressure, preventing stress on internal components, reducing the risk of leaks, and ensuring consistent hot water performance.

A failing or waterlogged expansion vessel can cause pressure fluctuations, dripping from the PRV, reduced hot water flow, or intermittent boiler operation. Replacing it with this genuine Glow-worm part restores proper pressure regulation and smooth system performance.

Key Features

• Genuine Glow-worm hot water expansion vessel

• Maintains stable DHW pressure during heating cycles

• Helps prevent over-pressurisation and PRV discharge

• Supports consistent hot water delivery and system protection

• Durable construction for long-term reliability

• Direct-fit replacement for fast, accurate installation

Compatible With

Suitable for selected Glow-worm boilers requiring DHW expansion vessel 0020038257.

Please confirm compatibility using your boiler manual or existing part number.