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INSPECTING bURNERS
Figure 23 - Correct Pilot Flame Pattern
Figure 21 - Incorrect Pilot Flame Pattern4
BURNER PRIMARY AIR HOLES
Air is drawn into the burner through the holes
in the fitting at the entrance to the burner.
These holes may become blocked with dust
or lint. Periodically inspect these holes for any
blockage and clean as necessary. 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 pres-
ent. All round burner flame holes should be
open with a small blue flame present. Some
burner flame holes may become blocked by de-
bris or rust, with no flame present. If so, turn off
heater and let cool. Remove blockage, blocked
burner flame holes will create soot.
Check pilot flame pattern and burner flame
patterns often.
PILOT FLAME PATTERN
Figure 23 shows a correct pilot flame pattern.
Figure 24 shows an incorrect pilot flame pat-
tern. 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 24
• turn heater off (see
To Turn Off Gas to Ap-
pliance
, page 18)
• see
Troubleshooting
, page 21
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.
Pilot Burner
Thermocouple
Pilot Burner
Thermocouple
CLEANING AND MAINTENANCE
WARNING: Turn off heater
and let cool before cleaning.
CAUTION: You must keep
control areas, burner and circu
-
lating 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 clean
-
ing due to excessive lint from
carpeting, bedding material, pet
hair, etc.
WARNING: Failure to keep
the primary air opening(s) of
the burner(s) clean may result in
sooting and property damage.
ODS/PILOT AND BURNER
Use a vacuum cleaner or small, soft bristled
brush to clean.
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 pro-
vides a clean burning flame. Keep these holes
clear of dust, dirt and lint. 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.