Hoshizaki 73183 User Manual

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IV. Service Diagnosis
 WARNING
1. This unit should be diagnosed and repaired only by qualified service 
personnel to reduce the risk of death, electric shock, serious injury, or fire.
2. Risk of electric shock. Use extreme caution and exercise safe electrical 
practices.
3. Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.
4. Make sure all food zones are clean after the unit is serviced. For cleaning 
procedures, see "VI. Cleaning Instructions."
A. Diagnostic Procedure
The diagnostic procedure is basically a sequence check that allows you to diagnose the 
electrical system and components. Before proceeding, check for correct installation and 
proper voltage per unit nameplate.  As you go through the diagnostic procedure, check 
to assure the components energize and de-energize correctly. If not, those components 
or controls are suspect. Always choose a white (W) neutral wire to establish a good 
neutral connection when checking high voltages. If the display module is in alarm, see 
"II.D.2. Alarm Safeties." For further details, see "IV.B. Control Module Check." For factory
default settings, see "II.C.2.a) Default Settings."
Note: When power is turned on, the 2-hour high-temperature alarm timer is bypassed. 
Therefore, a high-temperature alarm can occur at startup. To silence the alarm, 
press and release the upper button. Alarm clears once temperature is within 
factory parameters.
IMPORTANT
The maximum allowable voltage variation is ±10 percent of the nameplate 
rating. 115VAC is used as a reference voltage when checking voltage to 
components. Voltage may vary depending on power supply.
1) Move the power switch to the "OFF" position.
2) Unplug the unit from the electrical outlet.
3) Remove the control box cover.
4) Plug the unit back into the electrical outlet.
5) Move the power switch to the "ON" position.
6) Confirm proper supply voltage (115VAC) to the power switch. On 3-section 
units, also confirm proper supply voltage to the receptacle box (115VAC for 
refrigerator/208-230VAC for freezer). 
Continue to "IV.A.1. Refrigerator" or "IV.A.2. Freezer."