37
Inside fi rebox—roof venting port
10
0
Restrictors
ALL INSTALLATIONS REQUIRE A RESTRICTOR
for improved fl ame picture and performance. This unit
is supplied with a pre-fi tted restrictor having diff erent
positions or settings. The restrictor is shipped mounted
at the maximum open position. 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 confi 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.
The restrictors are located in the roof of the fi rebox
hidden above the top panel.
To access the restrictors, remove the top panel:
1. Release 4 screws along the back of the panel.
It is
not necessary to remove the screws
.
2. Remove 4 screws along the front of the panel.
3. Slide the panel forward to unhook it and set aside.
4. The restrictors are set in position 0 at the factory.
The position 0 is at the center and has the
restrictors wide open; the position 10 is the farthest
away from the center and has the restrictor closed
totally. Adjust the restrictors position as needed—up
to position 9—
DO NOT CLOSE ALL THE WAY TO
POSITION 10!
:
a) Establish the required position of the restrictors
looking up the appropriate venting table
(according to vent pipes size) on the previous
pages.
b) Remove the screws (2) on each restrictor
already installed
on the fi rebox roof port
.
c) Slide the restrictors in the required positions.
d) Refi t and tighten the screws.
5. Reinstall the top panel sliding it on the back screws
previously released; tighten the screws.
6. Refi t and tighten the screws at the front of the panel.
VENTING
QUALIFIED
INSTALLER
