Sirius three FS 50kW-250kW  


  • Outputs of 50kW, 70 kW, 90 kW, 110kW, 130kW, 150kW, 200kW and 250kW, making it suitable for a wide range of commercial applications
  • Wide 9:1 modulation ratio reducing constant on/off cycling to improve efficiency and boiler longevity
  • A gross seasonal efficiency of up to 97.5% reduces energy consumption
  • Supplied with the latest Siemens controls with state of the art PCB, offering improved control options
  • The QA75 Twist Knob Controller has a simple descriptive display and easy to use advanced programming functions
  • Programmable to work with solar thermal, biomass and buffer tanks, for a sustainable, energy efficient solution across the complete range
  • Suitable for LPG conversion; LPG conversion kits are available for off-grid applications
  • Lightweight stainless steel heat exchanger for reliable and energy efficient heat transfer
  • Integrated Low Loss Headers and Plate Heat Exchangers (available as options) are easier to install and offer a professional finish and reduced footprint
  • A very compact design, with casters on the bottom of larger output boilers. Boilers will pass through 700mm doors and are easier to position when space is at a premium
  • 1" flow and return connections (50-70kW) avoids major pipework modification
  • An integrated Cascade function allows up to 16 boilers to be managed by the Siemens controller
  • 0-10 volt connection provides a quick and simple interface with BMS
  • Weather compensation functionality reduces operation costs
  • A low NOx of under 24.6mg/kW minimises impact on the environment
  • ErP compliant, reducing carbon emissions and improving efficiencies in support of government targets
  • Certified for the ETL*, part of the Enhanced Capital Allowance (ECA) tax scheme for businesses
  • Five year parts and labour warranty** for complete peace of mind

At this link you can find all the technical information: