Design Dynamics PFS VF-18P-MHD - Manual (Page 21)

www.fmiproducts.com 116986-01H 21
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. Bad batteries (If batteries
fail within 1 heating season,
see cause no. 8)
3. Ignitor electrode not con-
nected to ignitor cable
4. Ignitor cable pinched or
wet
5. Broken ignitor cable
6. Bad piezo ignitor
7. Ignitor electrode positioned
wrong or broken
8. Bad module
1. Gas supply turned off or equip-
ment shutoff valve closed
2. Bad batteries (If batteries
fail within 1 heating season,
see cause no. 9)
3. Control knob not in PILOT
position
4. Control knob not pressed in
while in PILOT position
5. Air in gas lines when in-
stalled
6. Depleted gas supply (pro-
pane/LP only)
7. ODS/pilot is clogged
8. Gas regulator setting is not
correct
9. Bad module
1. Inlet gas pressure is too
low
2. Wire disconnected from gas
control
3. Burner orifice(s) clogged
4. Bad module
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
REMEDY
1. Push switch on valve to "–"
position
2. Replace batteries
3. Reconnect ignitor cable
4. Free ignitor cable if pinched
by any metal or tubing.
Keep ignitor cable dry
5. Replace ignitor cable
6. Replace piezo ignitor
7. Replace pilot assembly
8. Replace module
1. Turn on gas supply or open
equipment shutoff valve
2. Replace batteries
3. Turn control knob to PILOT
position
4. Press in control knob while
in PILOT position
5. Continue holding down
control knob. Repeat ignit-
ing operation until air is
removed
6. Contact local propane/LP
gas company
7. Clean ODS/pilot (see Clean-
ing and Maintenance, page
20) or replace ODS/pilot
assembly
8. Replace gas regulator
9. Replace module
1. Contact local natural or
propane/LP gas company
2. Reconnect leads (see Wir-
ing Diagram, page 24)
3. Clean burner (see Cleaning
and Maintenance, page 20)
or replace burner orifice(s)
4. Replace module