Service Diagnosis; Alarm Signals - Hoshizaki REFRIGERATED PREP TABLE WITH RAISED RAIL 73168 Service Manual

III. Service Diagnosis
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
Signal
High Temperature
Cabinet temperature has exceeded the
setpoint temperature by 18°F (10°C) for
more than x hours. The default value of
E1 8
x is "2".
Low Temperature Alarm
Cabinet temperature has remained
below the setpoint by 9°F (5°C) for more
E2
9 than y hours. The default value of y is
"1".
Defrost Alarm
Cabinet defrost has taken longer than
E3 7
1 hour. The control board has terminated
defrost.
WARNING
Alarm (cabinet only)
(cabinet only)
(cabinet only)
25
Reset, Corrections, and Adjustments
When the temperature returns to the setpoint
range, alarm resets.
Close doors/drawers and clean the condenser and
air filter. Check for refrigerant leaks. Check cabinet
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)
When the temperature returns to the setpoint
range, alarm resets.
Ambient temperature too low. Check thermistor,
liquid line valve sticking, fans not operating.
The value of y can be changed under "F4" on the
Service Menu.
(0=No delay; 1=hour)
Turn the power off, then back on.
Check defrost heater, defrost thermistor.
Note that "E3" may alternate with "dF" instead of
the temperature.