Desa VML27NR Operation And Installation Manual page 26

OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob is
released
Burner does not light after ODS/
pilot is lit
Delayed ignition burner
Burner backfiring during com-
bustion
6
tRouBLESHooting
Continued
POSSIBLE CAUSE
1. Control knob not fully pressed in
2. Control knob not pressed in
long enough
3. Equipment shutoff valve not
fully open
4. 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
5. Thermocouple connection
loose at control valve
6. Thermocouple damaged
7. Control valve damaged
1. Burner orifice clogged
2. Inlet gas pressure is too low
3. Thermopile leads disconnect-
ed or improperly connected
4. Burners will not come on in
remote position
1. Manifold pressure is too low
2. Burner orifice clogged
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 ODS/pilot lights, keep con-
trol knob pressed in 30 seconds
3. Fully open equipment shutoff
valve
4. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 23) or replace ODS/pilot
assembly
5. Hand tighten until snug, then
tighten 1/4 turn more
6. Replace pilot assembly
7. Replace control valve
1. Clean burner (see Cleaning
and Maintenance, page 23) or
replace burner orifice
2. Contact local natural or pro-
pane/LP gas company
3. Reconnect leads (see Wiring
Diagram, page 24)
4. Replace battery in transmitter
and receiver
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner (see Cleaning
and Maintenance, page 23) or
replace burner orifice
1. Clean burner (see Cleaning
and Maintenance, page 23) or
replace burner orifice
2. Replace damaged burner
3. Replace gas control
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