Desa Design Dynamics VTD-18NV-JHB Owner's Operation And Installation Manual page 14

OBSERVED PROBLEM
Pilot lights but flame goes out
when control knob is released
One or both burner does not light
after ODS/pilot is lit
Delayed ignition of burner
Burner backfiring during com-
bustion
14
TROUBLESHOOTINg
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 al-
lows thermocouple 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
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 clogged
3. Mislocated crossover tube
4. Remote selector in OFF
position
5. Wire disconnected from gas
control
1. Manifold pressure is too
low
2. Burner orifice clogged
3. Mislocated crossover tube
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
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REMEDY
1. Press in control knob fully
2. After pilot lights, keep control
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 pilot (see Cleaning
and Maintenance, page 13) or
replace 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 (see Cleaning
and Maintenance, page 12)
or replace burner orifice
3. Contact qualified service
person
4. Put remote selector in ON
position
5. See Wiring Diagram, page 17
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner (see Cleaning
and Maintenance, page 12)
or replace burner orifice
3. Contact qualified service
person
1. Clean burner (see Cleaning
and Maintenance, page 12)
or replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
114370-02C