Domestic unvented water heater and cylinders

OSO have a full range of domestic unvented water heaters up to 300 litres

OSO cylinders are made from 1.3mm thick stainless steel and are offered with a 25 year warranty. Direct cylinders are heated by electricity and are supplied with factory fitted immersion heater elements. Indirect cylinders are connected to a central heating system using a boiler (gas, oil or electric) or a heat pump (ground source, air source or water source). Infirect cylinders are also factory fitted with back up immersion heaters.  

OSO Super Series has unrivalled space efficiency and saves hours of labour time. 

OSO cylinders lead the world in energy efficiency. OSO Delta has the lowest standing heat loss of any comparable cylinder in the world. Delta uses Vacuum Insulation Panels (VIP) to achieve the best energy efficiency possible. Vacuum panel insulation is an award winning innovation for water heating and won “product of the year” by H & V news.  

OSO Super Xpress (SX) also uses VIP to achieve the best possible SAP ratings for builders of properties with electric heating. SX is the market leading product for electric water heaters in new build high-rise accomodation.

Direct – Electric heating

Indirect – Connect to boiler


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