MN702GE 060320
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Motor maintenance
• Refer to motor manufacturer’s instructions for oiling the motor as needed.
Checking ignitor
Never test an ignitor by placing a screwdriver (or other metallic
object) across the high voltage clips. This could cause ignitor
damage or severe personal injury.
1. Turn off the power to the burner/appliance.
2. Shut off gas supply to the burner.
3. Remove ignitor from back of panel.
4. Attach the spark plug clamp to the unpainted area of the ignitor plate
using the screw from step 3. This grounds the spark plug.
5. Connect the ignitor lead to the spark plug.
6. Reapply power to the burner and, after the pre-purge timing, observe the
spark.
7. If there is a spark, verify that the ignitor electrode is in the correct posi¬tion
and not grounded to the diffuser plate. Remove the spark tester and
replace the screw and ignitor lead.
8. If there is no spark, verify that there is 120 volts being supplied to the
ignitor. If there is not 120 volts supplied, then replace the ignitor.
Thermal fuse
1.
When the burner is in a high-overfire draft condition, and not properly
adjusted, it is possible that the flame could flash back inside the air tube.
If this occurs, the thermal fuse will open in less than two seconds. The
fuse must be replaced. (The burner is supplied with spare fuses.)
8. Maintenance and service procedures
When servicing the burner . . .
•
DISCONNECT ELECTRICAL SUPPLY and all other electrical connec-
tions to burner before attempting to service to avoid electrical shock or
possible injury from moving parts.
•
CLOSE all manual gas valves before disconnecting any portion of fuel
lines and before cleaning or removing any parts from the burner or
related equipment.
•
Burner and appliance components can be extremely hot. Allow all parts
to cool before attempting to handle or service to avoid potential of severe
burns.
Turn off power to appliance when servicing burner. After servicing,
always operate burner/appliance to verify all components are
functioning correctly and that the burner is properly adjusted.
Failure to comply could result in severe personal injury, death
or substantial property damage.
General maintenance
Cleaning blower wheel
1. The blower wheel accumulates dust and debris from normal operation.
You will need to clean the wheel blades periodically to prevent reduction
in airflow. Inspect the blower wheel regularly by opening the housing
cover.
2. To clean blades, when necessary, remove the bolts securing the motor
to the blower housing.
a. Slide the motor out and rotate to remove and access blower wheel.
b. Use a brush and vacuum to clean each blade and the blower housing
interior.
c. Install motor/wheel in blower housing and secure with the two bolts.
d. Push wire slack back into junction box.
Replacing blower motor or wheel
1.
If either the blower wheel or motor must be replaced, remove the bolts
securing the motor to housing.
2. Disconnect the motor wires in the burner panel.
3. Loosen the Allen screw securing the blower to the motor shaft and remove
the wheel.
4. When assembling the replacement assembly, slide the wheel onto the
motor shaft and use feeler gauges to set space between the blower wheel
and the motor face. This space must be 3/16 inch.
5. Install the motor/wheel assembly in the housing, wire the motor leads
and secure the motor with the two bolts.