Hoshizaki 73168 service manual III. Service Diagnosis, Alarm Signals

III. Service Diagnosis

WARNING

1.This unit should be disassembled or repaired only by a qualified service technician to reduce the risk of injury, electric shock, or fire.

2.Do not make any alterations to the unit. This could cause water leak, electric shock, or fire.

3.To help reduce the risk of electric shock, do not touch the attachment plug or switches with damp hands.

4.In case of insufficient refrigeration performance, move the stored food product into another unit to prevent its deterioration.

A. Alarm Signals

In the event of operation outside of normal parameters, the control board identifies the issue with an alarm signal. The alarm signal and cabinet temperature are displayed in

1-second intervals. For further service information, see "III.B. Service Chart." If multiple alarms occur simultaneously, only the alarm with the higher priority is displayed.

Alarm	Priority	Problem	Reset, Corrections, and Adjustments
Signal
		High Temperature Alarm (cabinet only)	When the temperature returns to the setpoint
			range, alarm resets.
		Cabinet temperature has exceeded the
		setpoint temperature by 18°F (10°C) for	Close doors/drawers and clean the condenser and
E1	8	more than x hours. The default value of	air filter. Check for refrigerant leaks. Check cabinet
		x is "2".	thermistor.
			The value of x can be changed under "F3" on the
			Service Menu.
			(0=No delay; 1=1 hour; 2=2 hours; 3=3 hours)
		Low Temperature Alarm (cabinet only)	When the temperature returns to the setpoint
			range, alarm resets.
		Cabinet temperature has remained
		below the setpoint by 9°F (5°C) for more	Ambient temperature too low. Check thermistor,
E2	9	than y hours. The default value of y is	liquid line valve sticking, fans not operating.
		"1".
			The value of y can be changed under "F4" on the
			Service Menu.
			(0=No delay; 1=hour)
		Defrost Alarm (cabinet only)	Turn the power off, then back on.
E3	7	Cabinet defrost has taken longer than	Check defrost heater, defrost thermistor.
		1 hour. The control board has terminated
		defrost.	Note that "E3" may alternate with "dF" instead of
			the temperature.

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