Zephyr Essentials Siena ZSI-E30AS Use, Care And Installation Manual page 9

WARNING FIRE HAZARD
NEVER exhaust air or terminate duct work into spaces between walls, crawl spaces, ceiling, attics or garages.
All exhaust must be ducted to the outside, unless using the recirculating option.
Use single wall rigid Metal ductwork only.
Some Ducting Options
ductless
recirculating
Roof Pitch w/
Flashing & Cap
Soffit or crawl space
side wall cap
w/ gravity damper
7
side wall cap
w/ gravity damper