Lennox O23 User Manual

Page 38
Burner runs continuously cont.
Source Procedure Causes Correction
Too much combustion air Reduce combustion air.
Low CO
2
less
Air leaks into heat exchanger
around inspection door, etc.
Correct cause of air leak.
L
ow
CO
2
l
ess
than 10%.
Excessive draft
Adjust barometric draft con
trol for correct draft.
Incorrect burner head adjust
ment
Correct burner head setting.
Dirty or plugged heat exchanger
Clean heat exchanger.
Hi h k
Di
r
t
y or p
l
ugge
d
h
ea
t
exc
h
anger
Readjust burner.
Check burner
High smoke
readin
g
more
Insufficient draft Increase draft.
Combustion
Ch
ec
k
b
urner
combustion for
CO2, stack tem
reading
more
than a trace. Incorrect burner head adjust
ment
Correct burner setting.
CO2,
stack
tem
perature, and
smoke
Too little combustion air Increase combustion air.
smo
k
e
Too little blower air
Increase blower speed to
maintain proper temp. rise.
Hi
g
h stack tem
Blower belt too loose (if
equipped)
Tighten blower belt.
High
stack
tem
perature is
more than
Dirty or plugged heat exchanger Clean heat exchanger.
more t
h
an
550
F Net.
Dirty blower wheel Clean blower wheel.
550 F
Net.
Dirty furnace air filters Clean or replace filter.
Restricted or closed registers or
dampers
Readjust registers or damp
ers.
Oil Pressure
Inspect fire and check
Partially plugged or defective
nozzle
Replace nozzle.
Oil
P
ressure
Inspect
fire
and
check
oil pressure.
Oil pressure is too low: less
than 100 psi.
Increase oil pressure top
100psi.
Troubelshooting O23 / OHR23 / OF23 −5 Units
Procedure Status Correction
CONDITION 1: BURNER DOES NOT ENERGIZE WITH A CALL FOR HEAT.
1.1 Check limit switch contacts are
closed and clean.
Clean contacts. Replace limit switch if necessary.
1.2 Check for line votage at oil pri
mary control. Voltage should be
120V
Check primary voltage source. Take appropiate measures to cor
rect if necessary.
1.3 Check LED light with burner off,
no call for heat (no flame)
LED is on
Cad cell or control is bad. Control sees external light or connections
are shorted. See step 1.4.
no ca
ll
f
or
h
eat
(
no
fl
ame
)
LED is off See step 1.5.
LED is off Eliminate exteranl light or shield light from cad cell
1.4 Sheild cad cell from external
light
LED stays on
Replace cad cell and recheck.
 If LED stays on remove cad cell lead wires from burner control
and recheck.
 If LED turns off, replace cad cell bracket assembly.
 If LED stays on replace buner control
1.5 On warm air systems, Remove
one thermostat lead and jumper
Burner energizes
Trouble in thermostat or limit circuit. Check thermostat or limit wir
ing connections.
one t
h
ermostat
l
ea
d
an
d
j
umper
thermostat (T to T) terminals on
burner control.
Burner does not energize
Disconnect line voltage power and open line switch
 Check all wiring and tighten any loose connections. Recheck
 If burner does not energize replace burner control

Lennox O23 Specifications

General

Brand	Lennox
Model	O23
Category	Furnace
Language	English