The following installation manuals are available for the Preeva - SDH/SHH/RDH/RHH range:
Preeva SDH & RDH - Installation Manual - https://www.reznor.co.uk/wp-content/uploads/2023/12/SDH_RDH_0.pdf
Preeva SDH EC & RDH EC - Installation Manual - https://www.reznor.co.uk/wp-content/uploads/2023/12/SDH-EC_RDH-EC_0.pdf