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.
Thermocouple
Blue Flame
Pilot Burner
Figure 21 - Correct Pilot Flame Pattern
Thermocouple
Yellow Flame
Pilot Burner
Figure 22 - Incorrect Pilot Flame Pattern
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.
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