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.