www.desatech.com
113097-01L
23
INSPECTING bURNERS
• turn heater off (see
To Turn Off Gas to
Appliance
, page 20 [manually-controlled
models] or page 22 [thermostat-controlled
models])
• see
Troubleshooting
, page
25
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 entrance to the burner.
These holes may become blocked with dust,
lint or pet hair. 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
debris or rust, with no flame present. If so,
turn off heater and let cool. Remove blockage.
Blocked burner flame holes will create soot.
Figure 33 - Correct Pilot Flame Pattern
Figure 34 - Incorrect Pilot Flame Pattern
Thermocouple
Pilot Burner
Thermocouple
Pilot Burner
CLEANING AND MAINTENANCE
Check pilot flame pattern and burner flame
patterns often.
PILOT FLAME PATTERN
Figure 33 shows a correct pilot flame pattern.
Figure 34 shows an incorrect pilot flame pat
-
tern. The incorrect pilot flame is not touching
the thermocouple. This will cause the thermo
-
couple to cool. When the thermocouple cools,
the heater will shut down.
If pilot flame pattern is incorrect, as shown
in Figure 34
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.
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, 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. If using compressed air in a can, please
follow the directions on the can. If you don’t
follow directions on the can, you could dam
-
age the pilot assembly.
