Lennox RAVELLE 30 Installation And Operation Instructions Manual page 21

Flue Restrictors
The flue restrictor settings shown in Figures 20 and 21 are for typical
installations and may need to be adjusted from standard to take into
account other variables in the installation to achieve proper combustion.
See Flue Restrictor Guidelines on this page to assist you in making a
proper flue restrictor adjustment.
The Ravelle™ 30 gas fireplace uses balanced flue technology to ensure
proper combustion . As such, flue restrictors may need to be installed
depending on the vent configuration of your fireplace . The drawings on
Page 22 show all the allowable pipe configurations for the Ravelle 30
gas fireplace . To properly install the flue restrictor, first find your pipe
configuration in the drawings on Page 22 and note which restrictor
setting is recommended . The flue restrictors and four black self-tapping
5/32" allen head screws can be found in the firebox in a plastic bag . The
restrictors should be placed over the openings at both sides of the ceil-
ing of the firebox . For each restrictor, two self-tapping 5/32" allen head
screws should be installed in either holes 1, 2, 3, 4, or 5 in the restrictor
and screwed into the two holes in the firebox ceiling . (Note: There are
four holes at each side of the firebox ceiling to receive only two screws.
Insert the screws into either two holes). See Figure 19 for the location
of hole numbers on the restrictor . The numbered holes in which the screws
are inserted in the restrictor should correspond to the restrictor position
numbers found on the drawings for your pipe configuration . Restrictor
positions are based on tests run in a laboratory . The optimum restrictor
positions may need to be adjusted slightly depending on the conditions
surrounding the residential installation . Do not adjust restrictors to a
point where the fireplace is sooting .
Notes: The higher the number of the flue restrictor position, the greater
amount of combustion air will be delivered.
Flue Restrictor Adjustment Guidelines
After the flue restrictors have been set to the standard settings as shown
in Figures 20 and 21, the burner flame appearance should be evaluated
to determined if the flue restrictors need to be set to a different position
to adjust for variables in your installation . Light the appliance and allow
it to burn for 20 minutes . See Flame Color and Behavior on Page 31 to
determine if you have a proper burner flame appearance . If the proper
flame appearance cannot be achieved, the flue restrictor may need to be
set to a different position . See the following guidelines to determine if
you need to readjust the flue restrictors .
Before proceeding, confirm the manifold and inlet gas pressure is correct,
primary air shutter is properly adjusted, venting system connections are
secure and not blocked and if you are at a high elevation, ensure unit has
been properly derated:
Symptoms - Lack of Combustion Air
If the symptoms listed below are present, you may need to adjust the
flue restrictor to a more open position .
• Flame appears yellow
• Floating Flames (lazy, ill defined, quiet, may roll)
• Sooting
• Pilot becomes yellow and appliance shuts down
Symptoms - Excessive Combustion Air
If the symptoms listed below are present, you may need to adjust the
flue restrictor to a more closed position .
• Low Flame
• Pilot pulls and appliance shuts down
• Pilot flame ghosts
Figure 19
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Restrictors
Interior of Firebox
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