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113061-01F
15
oPeRATING HeATeR
Continued
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 ther
-
mostats simply turn on and off the burner. The
thermostat used on this heater senses the room
temperature. The thermostat adjusts the amount of
gas flow to the burner. This increases or decreases
the burner flame height. 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. Selecting the 5 setting will cause the burner
to remain fully on without modulating down in
most cases.
Note:
The thermostat sensing bulb measures the
temperature of air near the heater cabinet. This
may not always agree with room temperature
(depending on housing construction, installation
location, room size, open air temperatures, etc.).
Frequent use of your heater will let you determine
your own comfort levels.
MANUAL LIGHTING
PROCEDURE
1. Remove front panel (see Figure 4, page 8).
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
Light-
ing Instructions
, page 14.
5. Replace front panel.
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 Appliance
)
• see
Troubleshooting
, page 17
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 Flame
Yellow Flame
BURNER FLAME PATTERN
WARNING: If yellow tipping
occurs, your heater could pro
-
duce increased levels of carbon
monoxide.
NOTICE: Do not mistake orange
flames with yellow tipping. Dirt
or other fine particles enter the
heater and burn causing brief
patches of orange flame.