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Figure 22 - Correct Pilot Flame Pattern
Figure 23 - Incorrect Pilot Flame Pattern
Pilot Burner
Thermocouple
Pilot Burner
Thermocouple
INSPEcTING BURNERS
BURNER pRIMARY AIR HOLES
Air is drawn into burner through holes in fit
-
ting at entrance to 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 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
debris or rust, with no flame present. If so,
turn off heater and let cool. Remove blockage,
blocked burner flame holes will create soot.
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.
Check pilot flame pattern and burner flame
patterns often.
pILOT FLAME pATTERN
Figure 22 shows a correct pilot flame pattern.
Figure 23 shows an incorrect pilot flame pat
-
tern. Incorrect pilot flame is not touching ther
-
mocouple. This will cause the thermocouple
to cool. When thermocouple cools, heater
will shut down.
If pilot flame pattern is incorrect, as shown
in Figure 23
• turn heater off (see
To Turn Off Gas to Ap-
pliance
, page 17
• see
Troubleshooting
, page 20
Note: Pilot flame on natural gas units will have
a slight curve, but flame should be blue and
have no yellow or orange color.
cLEANING AND MAINTENANcE
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.