Vulcan-Hart VC6ED, VCIEC, VC6EC, VC4ES, VC4ED Solid State Temperature Control Test, Troubleshooting

FULL SIZE ELECTRIC CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS

A.After the final adjustment is made and the average temperature is within tolerance, remove the knob and apply a non- permanent type sealer around the head of the set screw.

10.If the above adjustment cannot be obtained:

A.Turn the power switch OFF.

WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

B.Install a replacement thermostat and check calibration.

SOLID STATE TEMPERATURE

CONTROL TEST

1.Remove the right side panel as outlined under "COVERS AND PANELS" in "REMOVAL AND REPLACEMENT OF PARTS".

NOTE: If right side panel is not accessible, this component can be serviced by removing the control panel as outlined under "COVERS AND PANELS".

2.Place a thermocouple in the geometric center of the oven cavity.

NOTE: Oven temperature must be below 450°.

3.Set the temperature control to the maximum setting.

4.Check machine data plate for correct voltage to oven. Refer to diagram below for proper terminal locations and voltages before checking the control. Use the correct terminals for the corresponding voltage.

5.Turn the power switch to ON.

A.If correct, proceed to step 7.

B.If incorrect, problem is not with the temperature control. See

"TROUBLESHOOTING".

7.Check relay voltages on the board:

A.For 208-240VAC controls - check across terminals 7 & 10 for input to the internal relay and 6 & 10 for output from the internal relay.

1)If input voltage to the internal relay is correct, proceed to step 8. If input voltage to the internal relay is not present, problem is not with the temperature control. See

"TROUBLESHOOTING".

2)If output voltage from the internal relay is correct proceed to step 8. If output voltage from the internal relay is not correct, check temperature probe as outlined under

"TEMPERATURE PROBE TEST (SOLID STATE CONTROL)".

8.Set the temperature control to the minimum setting.

NOTE: Oven temperature must be above 300°F.

9.Check for zero (0) volts AC across terminals 6 & 10 (208-240VAC) for no output from the internal relay.

A.If correct, temperature control is functioning properly.

B.If incorrect, check temperature probe as outlined under "TEMPERATURE PROBE TEST (SOLID STATE CONTROL)".

1)If temperature probe is ok:

a. Turn the power switch OFF.

WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

b.Replace the temperature control and check calibration as outlined under "SOLID STATE TEMPERATURE CONTROL CALIBRATION".

6.Check for proper voltage across terminals 8 & 10 (208-240VAC) for power to the control.

Page 19 of 60 F25105 (December 2001)