107124-01E
For more information, visit www.desatech.com
For more information, visit www.desatech.com
22
INSPECTING BURNERS
Check pilot flame pattern and burner flame patterns often.
PILOT FLAME PATTERN
Figure 43 shows a correct pilot flame pattern. Figure 44 shows an
incorrect pilot flame pattern. 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 44
• turn heater off (see To Turn Off Gas to Appliance, page 20 [manu-
ally-controlled models] or page 21 [thermostat-controlled models])
• see Troubleshooting, pages 24 through 26
Figure 43 - Correct Pilot
Flame Pattern
Figure 44 - Incorrect Pilot
Flame Pattern
Thermocouple
Pilot Burner
Thermocouple
Pilot Burner
THERMOSTAT
CONTROL OPERATION
(Thermostat-Controlled Models Only)
The thermostat control knob can be set to any comfort level
between HI and LO. The thermostat will gradually modulate the
heat output and flame height from higher to lower settings, or
pilot, in order to maintain the comfort level you select. The ideal
comfort setting will vary by household depending upon the amount
of space to be heated, the output of the central heating system, etc.
Note:
Selecting the HI setting with the control knob will cause the
burners to remain fully on, without modulating down in most cases.
1.
Follow steps 1 through 5 under Lighting Instructions,
page 21.
2.
Depress control knob and light pilot with match.
3.
Keep control knob pressed in for 30 seconds after lighting
pilot. After 30 seconds, release control knob. Now follow
step 8, under Lighting Instructions, page 21.
MANUAL LIGHTING PROCEDURE
OPERATING HEATER
Continued
BURNER PRIMARY AIR HOLES
Air is drawn into the burner through the holes in the fitting at the
entrance to the burner. These holes may become blocked with dust,
lint, or pet hair. Periodically inspect these holes for any blockage and
clean as necessary. Blocked air holes will create soot.
MAIN BURNER
Periodically inspect all burner flame holes with the heater running. All
slotted burner flame holes should be open with yellow flame present.
All round burner flame holes should be open with a small blue flame
present. Some burner flame holes may become blocked by debris or
rust, with no flame present. If so, turn off heater and let cool, Remove
blockage. Blocked burner flame holes will create soot.
OPERATING HEATER (Thermostatically-Controlled Models
Thermostat Control Operation
Manual Lighting Procedurew
INSPECTING BURNERS
Pilot Flame Pattern
Burner Primary Air Holes
Main Burner
