Lochinvar LTN07575 Instruction Manual page 20

Draft Hood
Top of Heater
FIGURE 16. DRAFT HOOD ATTACHMENT
The vent pipe from the water heater must be no less than
the diameter of the draft hood outlet on the water heater
and must slope upward at least 1/4 inch per linear foot
(21 mm per meter). See
All vent gases must be completely vented to the outdoors
of the structure (dwelling). Install only the draft hood
provided with the new water heater and no other draft
hood.
Vent pipes must be secured at each joint with sheet metal
screws.
Vent
Screw Draft Hood
Vent to outdoors
or chimney
Screw
(page 20).
Figure 17
FIGURE 17. VENT PIPE MINIMUM UPWARD SLOPE
There must be a minimum of 6" (153 mm) clearance
between single wall vent pipe and any combustible
material. Fill and seal any clearance between single
wall vent pipe and combustible material with mortar
mix, cement, or other noncombustible substance. For
other than single wall, follow vent pipe manufacturer's
clearance specifications. To insure a tight fit of the vent
pipe in a brick chimney, seal around the vent pipe with
mortar mix cement.
Failure to have required clearances between vent piping
and combustible material will result in a fire hazard.
Be sure vent pipe is properly connected to prevent
escape of dangerous flue gases which could cause
deadly asphyxiation.
Chemical vapor corrosion of the flue and vent system
may occur if air for combustion contains certain chemical
vapors. Spray can propellants, cleaning solvents,
refrigerator and air conditioner refrigerants, swimming
pool chemicals, calcium and sodium chloride, waxes,
bleach and process chemicals are typical compounds
which are potentially corrosive.
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