Glow Worm Ultimate3 25kW System Boiler

Thanks to its efficiency rating of 89.7% and an ErP A-rating for central heating, this system gas boiler could potentially help you to reduce your carbon footprint as well as your energy bills.

With an output rating of 25kW, the Ultimate3 system boiler is perfectly suited to medium to larger homes with 1-2 bathrooms and up to 15 radiators. For bigger homes with more demand for hot water and central heating, we would recommend looking at the Ultimate3 Combi Gas Boiler range. This boiler range includes 30kW and 35kW.

It is important to note when purchasing a new or replacement system boiler, that you will need to allow additional space in your home for a hot water storage tank. Mains water is heated and stored in a separate hot water storage tank ready to be used when needed. For this reason, we don’t recommend system boilers for smaller homes with limited space. If your home has limited space, don’t panic because the Glow-worm Ultimate3 is also available as a combi boiler with a 30kW or 35kW output.