Glow Worm Boiler Review

Acquired by the Vaillant Group in 2001, Glow-worm combines UK heritage with advanced European engineering, producing reliable, efficient boilers at its Belper facility. In 2025, its combi boilers, including the Energy, Ultimate3, Easicom3, Compact, and MicraCom, are renowned for affordability, compact design, and energy efficiency, earning Made in Britain accreditation. Glow-worm combi boilers deliver instant hot water and central heating from a single unit, ideal for space-constrained homes like flats or small houses. Models like the Energy (25kW–35kW) and Compact (24kW–28kW) offer A-rated efficiency of ~90–94%, with flow rates of ~10–14 liters per minute, suitable for 1–2 bathrooms. Featuring automotive-grade aluminium or stainless steel heat exchangers, they ensure durability and low emissions. Ultra-compact (some as small as 626mm x 400mm x 270mm) and wall-mounted, they fit kitchen cupboards, with modern interfaces and Quiet Mark approval for low noise. Smart controls, like the MiGo app, enable remote operation, while features like Grundfos pumps enhance efficiency. Installer-friendly with flexible flue options, they offer 3–10 year warranties via Club Energy. Priced from £500–£1,555 (excluding installation), they’re budget-friendly, though some Trustpilot reviews (4.6/5 from 7,000) note issues with heat exchanger maintenance. Best for small to medium homes, larger properties may need Glow-worm’s system boilers. With Which? scores of 74% and 20% hydrogen-readiness, Glow-worm remains a reliable, eco-conscious choice.