Desa CDR3924PT Owner's Operation And Installation Manual page 21

OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob is
released
One or more burners do not light
after ODS/pilot is lit
Delayed ignition of one or more
burners
Burner backfiring during com-
bustion
Yellow flame in burner during
burner combustion
113183-01A
TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Control knob not fully pressed in
2. Control knob not pressed in
long enough
3. Safety interlock system has
been triggered
4. Equipment shutoff valve not
fully open
5. Pilot flame not touching
thermocouple, which allows
thermocouple to cool, caus-
ing pilot flame to go out. This
problem could be caused by
one or both of the following:
A) Low gas pressure
B) Dirty or partially clogged
ODS/pilot
6. Thermocouple connection
loose at control valve
7. Thermocouple damaged
8. Control valve damaged
1. Inlet gas pressure is too low
2. Burner orifice(s) clogged
3. Mislocated crossover tube
1. Manifold pressure is too low
2. Burner orifice(s) clogged
3. Mislocated crossover tube
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
1. Not enough air
2. Gas regulator defective
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REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep
control knob pressed in 30
seconds
3. Wait one minute for safety
interlock system to reset.
Repeat ignition operation
4. Fully open equipment shutoff
valve
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 19) or replace ODS/pilot
assembly
6. Hand tighten until snug, then
tighten 1/4 turn more
7. Replace pilot assembly
8. Replace control valve
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 19) or
replace burner orifice(s)
3. Contact qualified service
person
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 19) or
replace burner orifice(s)
3. Contact qualified service
person
1. Clean burner (see Cleaning
and Maintenance, page 19)
or replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
1. Check burner(s) for dirt
and debris. If found, clean
burner(s) (see Cleaning and
Maintenance, page 19)
2. Replace gas regulator
21