The following installation manuals are available for the Sonning2 range:
Sonning2 OHA - Installation Manual - May 2018 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Reznor-Sonning2-OHA-Installation-Manual-EN-2018-05-D301067.pdf
Sonning2 OHA RHE - Installation Manual - May 2018 - https://www.reznor.co.uk/wp-content/uploads/2023/12/Reznor-Sonning2-OHA-RHE-Installation-Manual-EN-2018-05-D301061.pdf