andrews WHC56 Installation And Service Manual page 18

When the intake/exhaust pipes pass through an enclosed space:
Intake pipe
16
Exhaust pipe
(Combustible material)
Ceiling
Suggested inspection openings
• If the ventilation of hidden part is not sufficient, install two or more
ventilation holes.
• If you install the exhaust pipe at the hidden part, install the access
hole for checking the full length of exhaust pipe with eye.
• If the partition wall goes right through the hidden part, be sure to
install the access hole near the wall.
Sloping up toward flue terminal
External wall,
combustible material