9
The three functions of the atomizing nozzle are atomization,
creating the oil spray pattern and metering the fuel . (See
Figure 22.)
Several precautions should be observed when installing an
oil nozzle. (See Figure 22).
1. Do not clean a dirty nozzle, replace it.
2. Do not bump nozzle with a wrench.
3. Do not touch nozzle with your fingers.
4. Install nozzle with a nozzle wrench.
5. Be sure strainer is in place and tight.
6. Do not over-tighten nozzle during installation.
Low Burner Pressure and Poor Combustion
A flex coupler can contribute to low burner pressure and poor
combustion if the following occurs:
1. The coupler is too long and causes a high amperage
burner motor reading.
2. The coupler is worn and slipping.
3. The fuel pump shaft is worn and rounded causing the
coupler to slip. (See Figure 23)
The proper mixture of fuel and air is delivered to the burner
through an air adjustment band located on the burner
housing. (See Figure 24)
The primary purpose of the combustion chamber liner is to
isolate the combustion process from the rest of the furnace
and prevent damage to the components and the cabinet.
Removing Combustion Air Adjustment Band
1. Remove oil pump. (See oil pump replacement.)
2. Remove 2 5/16" screws from air band.
3. Loosen 1 5/6" screw and remove band housing.
4. To replace, reverse steps 1-3.
2. 1/2" long ARC from the alternate terminal post to the
casing. The first test of the ignition transformer is to
check for continuity using an ohmmeter. An infinity
reading indicates a defective transformer. A 10,000 volt
voltmeter is recommended to test the ignition transformer
spark.
3. 1" long ARC from terminal to terminal.
Removing the Ignitor Transformer
1. Shut off power to the unit.
2. Remove white and black wires coming from transformer.
3. Loosen 2, 5/16' screws and turn on tie-down plates.
4. Fold back transformer and remove 2 Phillips head
screws and transformer.
5. To replace, reverse steps 1-4.
Electrode Setting (See Figure 21)
The electrode setting is carefully checked at the factory.
When servicing the burner electrodes, three procedures
should be performed:
1. Set the spacing.
2. Set the gap.
3. Remove the carbon accumulation.
4. Refer to Installation Instructions.
Removing Drawer Assembly
1. Shut off and disconnect power to unit.
2. Remove copper oil line from drawer assembly and
loosen at pump using a 7/16" open end wrench and
move out of way.
3. Mark position of lock plate.
4. Loosen 5/16" screw on lock plate.
5. Remove drawer assembly and set the spacing, gap and
remove any carbon accumulation.
6. To replace, reverse steps 1-5.
Figure 21
Figure 22
Figure 24
Figure 23