Desa 100,000 Btu/Hr Owner's Manual page 14

FAULT CONDITION
Heater ignites but control as-
sembly shuts heater off after
a short period of time
Code C4 or C5 appear on
control panel display
C4/C5 = Out of Fuel or Fault
14
trouBleSHooting
Continued
POSSIBLE CAUSE
1. Pump pressure incorrect
2. Dirty air intake, air output,
and/or lint filter
3. Dirty fuel filter
4. Obstruction in nozzle
5. Photocell assembly not
properly installed (not see-
ing the flame)
6. Dirty photocell lens
WARNING: High voltage!
7. Bad electrical connection
between photocell and con-
trol assembly
8. Defective photocell
9. Defective control assembly
1. Not enough fuel in tank to
maintain combustion
2. Heater inlet or outlet is cov-
ered and unit is not getting
enough air for combustion
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REMEDY
1. See Pump Pressure Adjust-
ment, page 16
2. See Air Output, Air Intake,
and Lint Filters, page 16
3. See Fuel Filter, page 17
4. See Nozzle Assembly,
page 17
5. Make sure photocell boot is
properly seated in bracket
6. Clean photocell lens
7. Check electrical connec-
tions. See Wiring Diagram,
page 20
8. Replace photocell
9. Replace control assembly
1. Add fuel and restart unit
2. Remove obstructions or
loose material from heater
inlet or outlet
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