Siriusly exciting.

Introducing the efficient new 50-250kW Sirius three range.

Find out more about the Sirius three range
Sirius 3
Output Dry weight Dimensions (WxHxD) Flue connection size ErP
400kW 359kg 692x1341x1405mm 180 N/A
525kW 424kg 692x1558x1405mm 180 N/A
  • Features & Benefits
  • Specifications
  • Dimensions
  • Literature
  • BIM
  • CAD
  • Enquiry
  • Stainless steel heat exchanger designed for maximum combustion performance and safety
  • Very compact design so it's easy to fit in confined spaces
  • Built in load sharing, spreading heat demand across two burners, reducing wear and tear on components
  • 0 - 10 V connections as standard for easy BMS interface
  • Free commissioning by Potterton Commercial engineers, ensuring optimum performance, efficiency and savings
  • Service plans are available for on-going support, whenever you need it
  • The controls can be programmed to work with solar thermal, biomass and buffer tanks
  • Five year parts and labour warranty*

* Terms and conditions apply. Click here for details.


Dimensions and clearance measurements for all models of the Sirius FS 400kW and 525kW are featured in the tables below.

If you can't find the information you are looking for, you may find it within the product literature.

If you would like to speak to your local Area Sales Manager, please complete the online form within the enquiry tab.


Sirius FS 400 525
A Width 692 692 
B Height 1405  1405 
C Depth 1341 1558



Sirius FS 400 525
1 Front 800 800
2 L Hand 400 400
3 Top 600 600
4 Back 600 600
5 R Hand 600 600

Learn more about the Sirius WH by downloading our product literature.

Download CAD files for this product using the links below. To access CAD files you will need the correct software installed to allow you to open .dwg files such as AutoCAD 

Speak to your Technical Sales Manager if you have any enquiries and they will get back to you as soon as possible.