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Section 7 Troubleshooting
7-2
Freas Safety Oven
Possible Causes/Test Procedure/Corrective Action:
1. Wiring (loose, broken or shorted):
Improper wiring is listed first because it is applicable to all symptoms. It is
not necessary to disassemble the oven and check all wiring and connections at
the first indication of a problem, but that whenever you suspect a component
is the cause of the problem you should also check all wiring and connections
associated with that component and/or problem).
2. Door/Gasket (misaligned/dirty):
Heat Loss - Inspect door gasket to make certain it fits firmly against the
chassis at all points. Replace if damaged .
3. Vent Shutter Cap:
Make sure the vent shutter cap is not closed. Open to maximum (to maintain
higher temperatures, vent shutter cap may have to be partially closed).
4. Loading:
Test the unit when empty: if results are satisfactory, the chamber was
improperly loaded. Redistribute the load.
5. "High Limit" Thermostat:
a. Ensure "High Limit" is set as outlined in the "Operation" section.
b. If the red pilot light is glowing at all times no matter the position of the
"High Limit" knob (at ambient temperature), the "High Limit" is bad and
should be replaced (See "Parts Replacement", Section 6).
6. RTD Sensor:
If the display flashes
display flashes
check the sensor for an open circuit.
Disconnect the RTD Sensor by disconnecting the 3-position connector at
bottom left corner of left side compartment (remove left outside panel) then
check resistance between pins 15 & 16 and compare the resistance of the
sensor with the table shown in Section 6. Also check the resistance between
the sensor sheath and any sensor lead, it should be 100 megohms or greater.
, check the sensor for a short circuit. If the
, check the sensor leads for loose connections or
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