Design Dynamics VTD-18N-PDG Gas Heater User Manual


 
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111826-02J16
TROUBLESHOOTING
Continued

ODS/pilot lights but ame goes
out when control knob is re-
leased
Burner does not light after ODS/
pilot is lit
Delayed ignition of burner
Burner backring during com-
bustion

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 ame 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 orice clogged
3. Remote selector in OFF
position
4. Wire disconnected from gas
control
1. Manifold pressure is too low
2. Burner orice clogged
1. Burner orice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
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 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 14) 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 (see Cleaning
and Maintenance, page 14)
or replace burner orice
3. Put remote selector in ON
position
4. See Wiring Diagram, page 14
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner (see Cleaning
and Maintenance, page 14)
or replace burner orice
1. Clean burner (see Cleaning
and Maintenance, page 14)
or replace burner orice
2. Replace damaged burner
3. Replace gas regulator