5. If there is voltage at the 2-prong
connector, inspect the igniter for:
A. cracks or damage to the
carbide tip.
B. Frayed or damaged wiring,
C. Properly seated pins in the
connector.
6. Use an Ohmmeter to check the
resistance of the igniter. Make
this check with the igniter at
room temperature (70'' - 75° F.)
Norton 201 (black leads):
45 - 250 Ohms,
7. Be sure the igniter is positioned
properly in the flame.
DIRECT SPARK IGNITERS
The igniter electrodes light the
burners almost instantly. No longer is
there a 30 second warm up period as
with the hot surface igniter. A spark
arcing between the igniter points
directly lights the main burners. The
igrnter electrodes are fixed in
position. There is no need to adjust
them in the field.
FIGURE 118
OSI IGNITER
The igniter mounts with a bracket to
one of the burners. A high voltage
wire connects it to the ignition
transformer of the IFC.
FIGURE 119
OSI IGNITER CONNECTION
1.
2.
3.
It is turned off after the flame sensor
detects flame. The igniters serve
only to light the burners, and do not
sense flame.
Check. If the furnace doesn't light
and gas does get to the burners,
make the following test. Before
conducting the test prepare a test
wire. Use a two foot length of
thermostat wire with about one inch
of insulation stripped from each end.
Unplug the igniter lead from the
IFC ignition transformer before
conducting this test.
Attach one end of the test wire
to any nearby sheet metal screw
on the furnace chassis.
USING A WELL INSULATED
PAIR OF PLIER$,
hold the
other end of the test wire
approximately 1 /8" from the I FC
ignition transformer.
A CAUTION: DO NOT ALLOW
THE TEST WIRE TO TOUCH ANY
PERSON. THIS IFC OUTPUTS A
HIGH DC VOLTAGE. SERIOUS
PERSONAL INJURY CAN RESULT.
4.
Call for heat at the furnace. The
induced draft blower will run for
30 seconds.
5. Insure that the induced draft
blower has closed all pressure
switches.
6. When the furnace tries for
ignition, a visible spark should
arc from the ignition transformer
to the test wire.
7. If there is no spark, be sure the
test wire end is within
1/8" of the
ignition transformer terminal and
the furnace is properly
grounded.
8.
If there is no spark, replace the
furnace IFC.
9. If there is spark between the test
wire and IFC ignition
transformer, remove the test
wire and reconnect the igniter
lead.
10. Initiate another ignition
sequence and check for spark
between the igniter electrodes.
11. If there is still no spark, check
that the:
• igniter wire has no breaks;
• igniter electrodes have a 1 /8"
gap;
• igniter porcelain is not
cracked;
• igniter is positioned properly;
• igniter mount is securely
attached.
96
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