The best boilers to keep you warm in 2021 - Confused.com

Apr 30, 2021 · A condensing boiler is an energy-efficient boiler that recovers heat energy from waste gases. By law, all new and replacement boilers must be condensing boilers. An A-rated condensing boiler runs at 92-94% efficiency. An old, non-condensing boiler runs at about 7 0% efficiency. You can tell whether you have a condensing boiler by looking at the