| Problem |
Cause |
Solution |
| Display flashes Opn & rEL. |
Open relay. Circuit inoperable. |
Replace Power Circuit Board.
|
| Display flashes “SHr” & “rEL” |
Shorted relay. Circuit inoperable. |
Replace Power Circuit Board. |
| Open heater. |
Test heater resistance (150.2 Ohms). Replace heater if necessary.. |
| Unplugged ribbon cable between Power and Main Circuit Boards. |
Verify ribbon cable connection.
|
| Display flashes "Opn & rEL". |
Temperature is below 75° F |
Normal display during warmup.
|
| Heater inoperable. |
Test heater resistance (150.2 Ohms). Replace heater if necessary.. |
| Probe inoperable. |
Check for open thermocouple wires from probe. Replace heater/probe assembly. |
| Relay inoperable. |
Replace power circuit board.
|
| Display shows "HHH" for an extended period of time and heater surface temperature is hot. |
Temperature is above 300°F (abnormal operation). |
Diagnostic circuit inoperable. Replace power circuit board.
|
| Display shows "HHH" for an extended period of time and heater surface temperature is cool. |
Probe is inoperable. |
Check for pinched thermocouple wires from probe. Replace heater/probe assembly.
|
