Desa Design Dynamics VF-18N-MHD, Owner'S Operation And Installation Manual

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116986-01B 1
TRoUBlesHooTING
WARNING: Turn off heater and let cool before servicing. Only a
qualified service person should service and repair heater.
CAUTION: Never use a wire, needle or similar object to clean
ODS/pilot. This can damage ODS/pilot unit.
Note:
All troubleshooting items are listed in order of operation.
POSSIBLE CAUSE
1. Switch in OFF position (mod -
ule gives long steady beep)
2. Ignitor electrode not con -
nected to ignitor cable
3. Ignitor cable pinched or wet
4. Broken ignitor cable
5. Bad piezo ignitor
6. Ignitor electrode positioned
wrong or broken
7. Bad module
1. Gas supply turned off or equip -
ment shutoff valve closed
2. Control knob not in PILOT
position
3. Control knob not pressed in
while in PILOT position
4. Air in gas lines when in -
stalled
5. Depleted gas supply (pro -
pane/LP only)
6. ODS/pilot is clogged
7. Gas regulator setting is not
correct
8. Bad module
1. Inlet gas pressure is too low
2. Wire disconnected from gas
control
3. Burner orifice(s) clogged
5. Bad module
1. Manifold pressure is too
low
2. Burner orifice(s) clogged
OBSERVED PROBLEM
When and are pressed at
the same time, there is no spark
at ODS/pilot
When and are pressed,
there is spark at ODS/pilot but
no ignition
Burner does not light after pilot
is lit
Delayed ignition burner
REMEDY
1. Push switch on valve to "–"
position
2. Reconnect ignitor cable
3. Free ignitor cable if pinched
by any metal or tubing. Keep
ignitor cable dry
4. Replace ignitor cable
5. Replace piezo ignitor
6. Replace pilot assembly
7. Replace module
1. Turn on gas supply or open
equipment shutoff valve
2. Turn control knob to PILOT
position
3. Press in control knob while in
PILOT position
4. Continue holding down con -
trol knob. Repeat igniting op -
eration until air is removed
5. Contact local propane/LP gas
company
6. Clean ODS/pilot (see Cleaning
and Maintenance , page 19) or
replace ODS/pilot assembly
7. Replace gas regulator
8. Replace module
1. Contact local natural or pro -
pane/LP gas company
2. Reconnect leads (see Wiring
Diagram , page 24)
3. Clean burner (see Cleaning
and Maintenance , page 19) or
replace burner orifice(s)
5. Replace module
1. Contact local natural or pro -
pane/LP gas company
2. Clean burner (see Cleaning
and Maintenance , page 19) or
replace burner orifice