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© 2022 Staheli West
136
Faults
Fault 18: Flame Detected (Pre-Purge)
Indicates that a flame has been detected when there should not be a flame.
Causes
Troubleshooting
Fixes
• Flame in boiler.
• Check for burning/smoldering
debris inside the boiler.
• Manually latch CR-1 relay on
to start the fan and blow out the
fire.
• Wait for flame to burn out.
• Moisture in the
flame detector
lens.
• Remove fish-eye lens and
photocell tip and inspect for
moisture (even the slightest
amount of moisture can cause
Fault 18 to occur).
• Clean and dry thoroughly the
whole
flame detector assembly
(This may require several minutes
to air out these components
completely) (Weatherproof if
needed).
• Wet photocell.
• Remove and inspect photocell.
• Dry photocell.
• Faulty
flame detector or
photocell.
• Perform “Test 1”.
• Replace flame detector or
photocell.
• Faulty wiring.
• Inspect the wiring for ground,
continuity, and proper voltage.
• Replace/Repair wiring.