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125324-01A
14
OPERATION
Continued
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 comfort level between 1 and 5. All
plaques will turn off and on.
Note: The thermostat sensing bulb mea-
sures 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 7, page 9).
2. Follow steps 1 through 5 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 sec-
onds after lighting pilot. After 30 seconds,
release control knob. Now follow step 9
under
Lighting Instructions
, page 14.
5. Replace front panel.
Thermocouple
Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame
INSPECTING HEATERS
Figure 20 - Correct Pilot Flame Pattern
Figure 21 - Incorrect Pilot Flame Pattern
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 FLAME PATTERN
WARNING: If yellow tipping
occurs, your heater could pro-
duce increased levels of car-
bon monoxide. If burner flame
pattern shows yellow tipping,
proceed with the following in-
structions.
NOTICE: Do not mistake orange
flames with yellow tipping. Dust
or other fine particles enter the
heater and burn causing brief
patches of orange flame.
Figure 22 shows a correct burner flame pat-
tern. If burner flame pattern is incorrect, as
shown in Figure 23, page 15,
• turn heater off (see
To Turn Off Gas to Ap-
pliance
, page 13)
• see
Cleaning
, page 15
Check pilot flame pattern and burner flame
patterns 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 thermocouple
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
, page 13)
• see
Troubleshooting
, page 16