Glowworm Ultracom 18 HXI / SXI Main Heat Exchanger (15CM) – Refurbished | Part No. 801621

When a Glowworm Ultracom or older Glowworm HXI/SXI/CXI boiler shows signs of heat exchanger failure — reduced heating output, corrosion, or persistent efficiency loss — the main heat exchanger is the component to replace. The Glowworm Ultracom 18 HXI SXI Main Heat Exchanger 801621 (15CM) is a fully refurbished replacement that restores efficient heat transfer from the burner to the heating circuit across a broad range of compatible Glowworm models.

This is a fully refurbished original Glowworm part, quality-checked by experienced engineers before dispatch. The unit measures 15CM in depth — always confirm this matches your existing heat exchanger before ordering, as different-depth variants will not fit correctly.

Compatible Boiler Models

Key Features

• Glowworm part number 801621 — direct OEM replacement, 15CM depth
• Fully refurbished: quality-checked by experienced engineers before dispatch
• Fits Glowworm 12/15/18 HXI, 18 SXI, 24 CXI and Ultracom 12/15/18 HXI, 18/30 SXI, 24/30 CX, 24 CXI
• Important: Verify heat exchanger depth is 15CM before ordering
• 12-month warranty included

Delivery & Returns

Orders placed before 1:00 PM (Monday–Friday) are dispatched the same working day. Standard and next-day delivery options available at checkout. Next-day orders placed on Fridays arrive Monday — select Saturday delivery at checkout for weekend delivery. Returns accepted within 30 days if unused and in original packaging.

Note: Installation must be carried out by a Gas Safe registered engineer.