Vulcan-Hart VCE20H 126172 Electric Combi Ovens - Troubleshooting, Symptom, Possible Causes

ELECTRIC COMBI OVENS - TROUBLESHOOTING

SYMPTOM		POSSIBLE CAUSES
No steam generation but cavity fan	1.	Cavity temperature is above steam temperature set point
operates.		and oven is performing automatic cooling before steam
		generation can start.
	2.	Water supply off.
	3.	Steam generator thermal fuse(s) open.
	4.	Steam generator heating element(s) malfunction.
	5.	Contactor(s) malfunction. See “HEATING MODE AND
		CAVITY FAN SPEEDS” under “ELECTRICAL
		OPERATION”.
	6.	Lime scale build up (moist) on water level sensors giving
		false reading. See note at the beginning of
		troubleshooting section.
	7.	Oven control board malfunction.
Oven displays “888F” or “888C” in the	1.	Cavity temperature probe.
temperature display.		NOTE: On 10 level machines - error in the single cavity
		temperature probe. On 20 level machines - error in the
		upper cavity temperature probe.
		A. Damaged probe or thermocouple lead wire open.
		B. Board connection loose or connector not inserted
		onto board properly (mis-aligned).
		C. Thermocouple lead wires reversed. When heating,
		cavity temperature will appear to decrease for
		several seconds, then error code will display.
	2.	Low or no voltage on battery backup to maintain controls
		setup and program information in SRAM. See “BATTERY
		BACKUP - PROGRAMMABLE CONTROL” under
		“SERVICE PROCEDURES AND ADJUSTMENTS”.
	3.	Incorrect temperature probe in use. Ensure the
		temperature probe is not a thermistor type by checking its
		resistance. If resistance measures approximately 110
		ohms at 70-80°F then do not use.)
Oven displays “999F" or “999C" in the	1.	Cavity temperature probe.
temperature display.		NOTE: On 10 level machines - error in the single cavity
		temperature probe. On 20 level machines - error in the
		lower cavity temperature probe.
		A. Damaged probe or thermocouple lead wire open.
		B. Board connection loose or connector not inserted
		onto board properly (mis-aligned).
		C. Thermocouple lead wires reversed. When heating,
		cavity temperature will appear to decrease for
		several seconds, then error code will display.
	2.	Low or no voltage on battery backup to maintain controls
		setup and program information in SRAM. See “BATTERY
		BACKUP - PROGRAMMABLE CONTROL” under
		“SERVICE PROCEDURES AND ADJUSTMENTS”.
	3.	Incorrect temperature probe in use. Ensure the
		temperature probe is not a thermistor type by checking its
		resistance. If resistance measures approximately 110
		ohms at 70-80°F then do not use.)

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