The following installation manuals are available for the ECA range:
Benson ECA Gas - Installation Manual - November 2005 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Benson-ECA-Installation-Manual-Gas-EN-2005-11-20-45-363-Iss-1.pdf
Benson ECA Oil - Installation Manual - November 2005 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Benson-ECA-Installation-Manual-Oil-EN-2005-11-20-45-362-Iss-1.pdf