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107902-01L
14
INSPECTING HEATER
Check pilot flame pattern and burner flame
pattern often.
PILOT FLAME PATTERN
Figure 20 shows a correct pilot flame pattern.
Figure 21 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 21
• turn heater off (see
To Turn Off Gas to Ap-
pliance
)
• see
Cleaning
, page 15
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.
OPERATION
Continued
BURNER FLAME PATTERN
Figure 22 shows a correct burner flame pat-
tern. Figure 23 shows an incorrect burner
flame pattern.
If burner flame pattern is incorrect, as shown
in Figure 23
• turn heater off (see
To Turn Off Gas to Ap-
pliance
)
• see
Cleaning
, page 15
Thermocouple
Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame
Figure 20 - Correct Pilot Flame Pattern
Figure 21 - Incorrect Pilot Flame Pattern
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Turn control knob clockwise
to the
OFF position.
2. Turn off all electric power to the appliance
if service is to be performed.
3. Close equipment shutoff valve (see Figure
14, page 12).
MANUAL LIGHTING
PROCEDURE
1. Remove front panel (see Figure 10,
page 9).
2. Follow steps 1 through 7 under
Lighting
Instructions
, page 13.
3. With control knob pressed in, strike match.
Hold match to pilot until pilot lights.
4. Keep control knob pressed in for 30 sec-
onds after lighting pilot. After 30 seconds,
release control knob. Now follow step 9,
under
Lighting Instructions
, page 13.
5. Replace front panel.
Figure 22 - Correct
Burner Flame
Pattern
Figure 23 -
Incorrect Burner
Flame Pattern
LOW
OFF
PILOT
HIGH
OFF
PILOT
OFF
Control Knobs Burners
Figure 19 - Burner Patterns
