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1
INSPECTING HEATER
Check pilot flame pattern and burner flame pat
-
terns often.
PILOT FLAME PATTERN
Figure 30 shows a correct pilot flame pattern.
Figure 31 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 31
• turn heater off (see
To Turn Off Gas to Appli-
ance
, page 19)
• see Troubleshooting
, page 23
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.
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.
Pilot Burner
Thermocouple
Figure 30 - Correct Pilot Flame Pattern
(Your pilot may vary from pilots shown)
Pilot Burner
Thermocouple
Figure 31 - Incorrect Pilot Flame Pattern
(Your pilot may vary from pilots shown)
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 ar
-
eas 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.
We also recommend that you keep the burner
tube and pilot assembly clean and free of dust and
dirt. To clean these parts we recommend using
compressed air no greater than 30 PSI. Your local
computer store, hardware store, or home center
may carry compressed air in a can. You can use a
vacuum cleaner in the blow position. If using com
-
pressed air in a can, please follow the directions on
the can. If you don't follow directions on the can,
you could damage the pilot assembly.
1. Remove control cover log and front log.
2. Shut off the unit, including the pilot. Allow
the unit to cool for at least thirty minutes.
3. Inspect burner, pilot, and primary air inlet
holes on injector holder for dust and dirt (see
Figures 32 and 33, page 22).