Reznor B Unit Installation Manual - Manual (Page 17)

Form I-F/B, P/N 98126 R21, Page 17
Slope upward at
least 1/4” per foot
(6mm per 305mm)
Tee
with cap
installed
Small
diameter
tubing
to drain
FIGURE 13 - Vent with
Condensate Drain
8. The vent connection may be made into a suitable permanent chimney or into a
gas vent. The effective area of the vent connector, gas vent or chimney when
connected to a single appliance shall not be less than the area of the appliance
drafthood outlet or in accordance with approved venting methods. The effective
area of the gas vent or chimney when connected to more than one appliance shall
not be less than the area of the largest vent connector plus 50% of the areas of
additional vent connectors or in accordance with approved venting methods.
Minimum permissible height of the vertical vent is five feet (1.5M) providing no
horizontal vent pipe connector is used. If a horizontal vent connector is necessary,
consult Vent Run Length Tables on page 18 or the National Fuel Gas Code or
the Canadian Installation Code for Gas Burning Appliances, for the maximum
permissible length of a horizontal pipe run (vent connector) for a given vertical
height of gas vent.
The gas vent or chimney should extend at least three feet (1M) above the highest
point where it passes through a roof of a building and at least two feet (.6M) higher
than any portion of a building or obstruction within a horizontal distance of ten
feet (3M). Terminate the vent pipe with a Reznor Option CC1 vent cap. ( NOTE:
When installing a Size 125, run the required 7" vent pipe and use a field-supplied
increaser to attach an 8" vent cap.)
See illustrations in FIGURES 14, 15, and 16.
is recommended. Where it is necessary to run the vent pipe through an exterior
wall of combustible materials, a suitable thimble must be used. The vent pipe shall
have a clearance of at least six inches (152mm) from combustible materials, or as
is specified by the double-wall vent pipe manufacturer.
4. With the outlet on the heater in the horizontal position, it is recommended that a
12-18" (305-457mm) piece of straight pipe be connected to the flue collar before
installing an elbow. The horizontal vent pipe run should have a uniform rise of at
least 1/4" per foot (6mm per 305mm) of horizontal run in the direction of discharge.
The length of the lateral run must not exceed lengths showing in the vent tables
of the National Fuel Gas Code or the Canadian Installation Code for Gas Burning
Appliances. (See Vent Table on page 18.)
5. Lateral runs should be supported every six feet (1.8M) using a non-combustible
material, such as strap steel or chain. Do not rely on the drafthood or heater for
support of either horizontal or vertical vent pipe.
6. Vent connectors serving Category I heaters shall not be connected into any portion
of a mechanical draft system operating under positive pressure.
7. Where it is necessary to use a long run of vent pipe, or where the vent pipe is
exposed to cold air, condensation within the pipe may occur. There are two ways
to overcome or eliminate this problem.
(a) Prevent condensation by insulating the pipe so that the temperature of the flue
products never drops below 250°F.
(b) Use double-wall, Type B vent pipe which is recommended for the reduction or
elimination of condensate problems. Where extreme conditions are present and
condensate is anticipated, install a drain for condensate. (See FIGURE 13.)