Our Greenstar Heatslave II is the UK's most popular external oil combi boiler with flow rates up to 22l/min. Suitable for small, medium and large sized properties, this boiler features a robust weatherproof cabinet and a one piece stainless steel primary baffle and cross firing burner.Additional features and benefits: |Compatible with our Greenstar Comfort controls. |IP45 Protection - protecting the boiler from water, dust and external elements. |5 year guarantee on Worcester primary heat exchanger. |80/125mm room sealed flues with lengths of up to 8m available. |Plume management of up to 5m with conventional and flexi-flue kits also available.