Figure 9
Draft hood Inst allation
Sheet Metal Screws (four provided)
Draft hood
Legs
Legs
Slot
Slot
Jacket top
Install the draft hood with
the four screws provided.
Vent Pipe Size
It is important that you follow the guidelines in these
instructions for sizing a vent pipe system. If a transition to
a larger vent size is required, the vent transition connection
must be made at the draft hood outlet.
Vent Connectors
1. Type B, Double wall, U.L. Listed Vent Pipe.
2. Single wall Vent Pipe.
Maintain the manufacturer’s specified minimum clearance
from combustible materials when using type B double wall
vent pipe.
Vent connectors made of type B, double wall vent pipe
material may pass through walls or partitions constructed
of combustible material if the minimum listed clearance is
maintained.
Maintain a six inch minimum clearance from all combustible
materials when using single wall vent pipe.
IMPORTANT: Single wall vent pipe cannot be used for
water heaters located in attics and may not pass through
attic spaces, crawl spaces or any confined or inaccessible
location. A single wall metal vent connector cannot pass
through any interior wall.
When installing a vent connector, please note the following:
•
Install the vent connector avoiding unnecessary bends,
which create resistance to the flow of vent gases.
•
Install without dips or sags with an upward slope of at
least 1/4-inch per foot.
•
Joints must be fastened by sheet metal screws or other
approved means. It must be supported to maintain
clearances and prevent separation of joints and
damage.
•
The length of the vent connector cannot exceed 75% of
the vertical vent height.
•
The vent connector must be accessible for cleaning,
inspection, and replacement.
•
Vent connectors cannot pass through any ceiling, floor,
firewall, or fire partition.
•
It is recommended (but not mandatory) that a minimum
12 inches of vertical vent pipe be installed on the draft
hood prior to any elbow in the vent system to improve
conditions for positive flow of venting gases.
IMPORTANT: Existing vent systems must be inspected for
obstructions, corrosion, and proper installation.
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