Valor Madrona MF28JN Installation & Owner's Manual page 26

QUALIFIED
INSTALLER
Restrictors
SOME INSTALLATIONS REQUIRE RESTRICTORS.
For improved fl ame picture and performance, this unit
is supplied with two diff erent sets of vent restrictors.
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 restrictors.
26
Venting
INSTALL RESTRICTORS HERE
50
Restrictor 50
The chart on the previous page shows the vent
restrictor required relative to the length of the vent pipe.
Restrictors are not required for co-linear applications.
To install restrictors:
1. Remove every second screw from the exhaust ports
in the top of the fi rebox.
2. Install the restrictors with the removed screws.
75
OR
Restrictor 75