29
Position #1
Position #2
Position #3
Position #4
Position #5
Inside
fi
rebox—roof venting port
Restrictor
The restrictor is located in the roof of the
fi
rebox hidden
above the top liner panel. Adjust the restrictor before
installation of the top liner panel. Should subsequent
adjustment be required, you will need to remove the
top liner panel—see page 37.
ALL INSTALLATIONS REQUIRE A RESTRICTOR
for
improved
fl
ame picture and performance. This unit is
supplied with a pre-
fi
tted restrictor having
fi
ve different
positions or settings. The restrictor is shipped mounted
at the maximum open position which is used for rear
venting with no vertical rise. The level of restriction
required depends on the vertical rise in the venting
system and, to a lesser degree, the horizontal run and
number of elbows.
The amount of restriction is based on laboratory tests.
The ideal restrictor position may vary slightly, especially
when the vent pipe length is near the limits of the
acceptable con
fi
gurations for each type of restrictor.
The chart on the previous page shows the vent
restrictor required relative to the length of
the vent pipe.
To set the restrictor position:
1. Establish the required position of the
restrictor looking up the venting table
on the previous page.
2. Release the screws (2) on each side
of the restrictor already installed
on
the
fi
rebox roof port
.
3. Slide the restrictor in the required
position.
4. Tighten the screws.
Co-axial Venting
QUALIFIED
INSTALLER
Summary of Contents for 1500INO (NG)
Page 56: ......
