a) If you have already purchased and received the CV, you must contact the manufacturer of the CV to find out if it can be installed upside down.
or
b) If you have not purchased the CV yet, contact three (or more) CV manufacturers and ask if they make one to fit your operating conditions that can be installed upside down.
or
c) Hire an experienced Piping Designer to design your system so the CV is installed right side up.
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