The following installation manuals are available for the GUH range:
Benson GUH Natural Gas - Installation Manual - March 2005 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Benson-GUH-Installation-Manual-Natural-Gas-EN-2005-03-Iss-5.pdf
Benson GUH Propane - Installation Manual - October 2002 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Benson-GUH-Installation-Manual-Propane-EN-2002-10-Iss-3-1.pdf
Benson GUHBD Natural Gas - Installation Manual - October 2002 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Benson-GUH-Installation-Manual-Propane-EN-2002-10-Iss-3.pdf