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111035-01F
5
INSPECTING BURNERS
Check pilot flame pattern and burner flame pat
-
terns often.
PILOT FLAME PATTERN
Figure 38 shows a correct pilot flame pattern.
Figure 39 shows an incorrect pilot flame pattern.
The incorrect pilot flame is not touching the
thermocouple. This will cause the thermocouple
to cool. When the thermocouple cools, the heater
will shut down.
If pilot flame pattern is incorrect, as shown in
Figure 39
• turn heater off (see To
Turn Off Gas to Appli-
ance
, page 21 [Manually-Controlled Models]
or page 23 [Remote-Ready Models])
• see
Troubleshooting
, page 27
Note:
The pilot flame on natural gas units will
have a slight curve, but flame should be blue and
have no yellow or orange color.
Figure 38 - Correct Pilot Flame Pattern
(Your pilot may vary from pilots shown)
Pilot Burner
Thermocouple
Pilot Burner
Thermocouple
Figure 39 - Incorrect Pilot Flame Pattern
(Your pilot may vary from pilots shown)
BURNER PRIMARY AIR HOLES
Air is drawn into the burner through the holes in
the fitting at the burner entrance. These holes may
become blocked with dust or lint. Periodically
inspect these holes for any blockage and clean if
needed. Blocked air holes will create soot.
MAIN BURNER
Periodically inspect all burner flame holes with
the heater running. All slotted burner flame holes
should be open with yellow flame present. All
round burner flame holes should be open with a
small blue flame present. Some burner flame holes
may become blocked by debris or rust, with no
flame present. If so, turn off heater and let cool.
Remove blockage. Blocked burner flame holes
will create soot.
CLEANING AND
MAINTENANCE
WARNING: Turn off heater
and let cool before cleaning.
CAUTION: You must keep
control areas, burners and
circulating air passageways
of heater clean. Inspect these
areas of heater before each use.
Have heater inspected yearly
by a qualified service person.
Heater may need more frequent
cleaning due to excessive lint
from carpeting, pet hair, bedding
material, etc.
WARNING: Failure to keep
the primary air opening(s) of
the burner(s) clean may result in
sooting and property damage.
BURNER INjECTOR HOLDER AND
PILOT AIR INLET HOLE
The primary air inlet holes allow the proper
amount of air to mix with the gas. This provides
a clean burning flame. Keep these holes clear of
dust, dirt, lint and pet hair. Clean these air inlet
holes prior to each heating season. Blocked air
holes will create soot. We recommend that you
clean the unit every three months during operation
and have heater inspected yearly by a qualified
service person.