Lennox OHR23-105, Installation Instructions Manual

Page: 22 / 24

Page 22
Troubleshooting: Burner starts and fires, but lock out on safety.
Source Procedure Check Causes Correction
Poor Fire If burner
contin es to Unbalanced fire Replace nozzle
continues to
run, this may
be due to
Too much air − −lean short
fire Reduce combustion air − check
combustion.
be due to
poor fire.
Inspect fire.
Too little air − − long dirty
fire Increase combustion air − check
combustion.
After burner
p
Excessive draft Adjust barometric damper for correct
draft.
After burner
fires,
i di t l
Too little draft or restriction Correct draft or remove restriction.
Flame
Detector
,
immediately
jumper across
If fire is good,
fault is in the Dirty cad cell face Clean cad cell face.
Detector
jumper across
flame detector
terminals at the
primary control.
fault is in the
flame
detector.
Check
Faulty cad cell − exceeds
15000 hms Replace cad cell.
primary control.
Check
detector
circuit.
Loose or defective cad cell
wires Secure connections or replace cad cell
holder and wire leads.
Primary
Control If burner locks
out on safety,
fault is in the
primary
control. Primary control circuit
defective Replace primary control.
Troubleshooting: Burner Starts and Fires, but Loses Flame and Lock Out on Safety
Source Procedure Check Causes Correction
Poor Fire If burner continues
to r n (does not Unbalanced fire Replace nozzle
to run (does not
lock out of safety),
fault may be due to
Too much air − − lean short fire Reduce combustion air −
check combustion.
fault may be due to
poor fire. Inspect
fire.
Too little air − − long dirty fire Increase combustion air −
check combustion.
Excessive draft Adjust barometric damper for
correct draft.
After burner
fires
Too little draft or restriction Correct draft or remove
restriction.
Flame
Detector
fires,
immediately
If fire is good, fault
is in the flame Dirty CAD cell face Clean CAD cell face.
Detector
immediately
jumper across
flame
detector
is in the flame
detector. Check
detector circuit.
Faulty CAD cell − − exceeds
15000 hms Replace CAD cell.
detector
terminals at
the primary
detector circuit.
Loose or defective cad cell
wires Secure connections or replace
cad cell holder and wire leads.
Oil Supply
the primary
control.
If burner loses
flame (does not Pump loses prime − air slug Prime pump at bleed port
flame (does not
lock out on safety),
fault is in the fuel
system.
Pump loses prime − air leak in
supply line Check supply line for loose
connections and tighten
fittings.
system.
Water slug in line Check oil tank for water (over
1 inch) pump or drain out
water.
Partially plugged nozzle or
nozzle strainer Replace nozzle.
table continued on next page