Duke DSO 500, Service Manual

Page: 64 / 80

Service Manual for Speed Oven Model DSO 500
64
FRONT THERMAL COOLING FAN
REPLACEMENT
General
The front thermal cooling fan, Figure 33, is lo-
cated directly behind the top, front panel of the
oven and is accessed through the oven top panel.
The thermal cooling unit consists of a double shaft
end motor with a “squirrel cage” fan unit attached
to each motor shaft. The thermal cooling fan will
operate anytime the oven cabinet temperature is
above 40°C. The thermal cooling fan will function
independent of the MASTER ON/OFF switch
setting.
This fan cools the magnetrons, high voltage
transformers, and door switches.
Figure 33. Front Thermal Cooling Fan
Replacement Procedure
1. Disconnect and isolate the oven from the
power source.
2. Remove the oven top panel to gain access
to the thermal cooling fan motor and “squirrel
cage” fans.
3. Remove all metal ducting and shrouds.
4. Disconnect and label all wiring to the thermal
cooling fan motor.
5. Remove motor mounting screws and nuts and
remove the motor and “squirrel cage” fans as
a complete assembly.
6. Install the new thermal cooling fan unit and
replace and secure all mounting hardware.
Be sure the rubber grommets are in place.
9. Reconnect all wiring to the thermal cooling
fan motor.
10. Reinstall all metal ducting and shrouds.
11. Reinstall the oven top panel.