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15
107882-01M
OPERATING HEATER
Continued
INSPECTING HEATER
Check pilot flame pattern and burner flame pat-
tern often.
PILOT FLAME PATTERN
Figure 21 shows a correct pilot flame pattern. Figure
22 shows an incorrect pilot flame pattern. The incor-
rect 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 22
• turn heater off (see
To Turn Off Gas to Ap-
pliance
)
• see
Troubleshooting
, page 18
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.
Figure 22 - Incorrect Pilot Flame Pattern
Figure 21 - Correct Pilot Flame Pattern
Thermocouple
Pilot Burner
Pilot Burner
Thermocouple
Blue Pilot Flame
Yellow Pilot Flame
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.
Shutting Off Burner Only (pilot stays lit)
Turn control knob clockwise
to the
PILOT position.
THERMOSTAT CONTROL
OPERATION
The thermostatic control used on these models
differs from standard thermostats. Standard
thermostats simply turn on and off the burner.
The thermostat used on this heater senses the
room temperature. At times the room may
exceed the set temperature. If so, the burner
will shut off. The burner will cycle back on
when room temperature drops below the set
temperature. The control knob can be set to
any heat level between 1 and 5. This adjusts the
amount of gas flow to the burner that increases
or decreases the burner flame height.
Note:
The thermostat sensing bulb measures
the temperature of air near the heater cabinet.
This may not always agree with room tem-
perature (depending on housing construction,
installation location, room size, open air tem-
peratures, etc.) Frequent use of your heater will
let you determine your own comfort levels.
MANUAL LIGHTING
PROCEDURE
1. Remove front panel (see Figure 7, page 9).
2. Follow steps 1 through 7 under
Lighting
Instructions,
page 14.
3. With control knob pressed in, strike match.
Hold match to pilot until pilot lights.
4. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob. Now follow step 9, under
Lighting Instructions
, page 14.
5. Replace front panel.