Desa VUL18 - Manual (Page 29)

www.desatech.com 119426-01A 29
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 ther-
mocouple, which allows ther-
mocouple to cool, causing
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
4. Remote selector in OFF position
(Remote-Ready models only)
5. Wire disconnected from gas control
(Remote-Ready models only)
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
REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep con-
trol knob pressed in 30 seconds
3. Wait one minute for safety in-
terlock 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 26) 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 26) or
replace burner orifice(s)
3. Contact qualified service person
4. Put remote selector in ON
position
5. See Wiring Diagram, page 27
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 26) or
replace burner orifice(s)
3. Contact qualified service person
1. Clean burner (see Cleaning
and Maintenance, page 26)
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 26)
2. Replace gas regulator
OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob is
released
One or both burners do not light
after ODS/pilot is lit
Delayed ignition of one or both
burners
Burner backfiring during com-
bustion
Yellow flame in front burner
during burner combustion
TROUbLESHOOTING
Continued