Hoshizaki EE(E5) Error Code — What It Means
On Hoshizaki ice machines, EE is a generic error display. The actual fault code is stored in the controller’s error log. When your service manual or error history shows E5, that specific code means high voltage — the voltage supplied to the machine is too high. Many Hoshizaki models display only EE on the live screen when errors other than E1 or E2 occur, so a technician must read the log to confirm the E5 event.
For machines on the 115 V platform, high-voltage alarms typically trip when incoming voltage exceeds roughly 147 volts (± 5%). Once correct voltage is restored, the alarm resets automatically. The error can be caused by utility overvoltage, incorrect wiring on a high-leg or split-phase supply, or less commonly a control-board sensing issue.
Before You Replace Anything
Technicians sometimes replace the main control board before measuring supply voltage. Always measure incoming voltage at the machine under load and verify correct phase-to-neutral wiring first.
Common Causes
- Utility overvoltage (~50%) The incoming line voltage at the branch circuit or supply transformer is too high and exceeds the machine’s acceptable range.
- High-leg or stinger supply (~30%) The machine is connected to the wrong leg of a split-phase or three-phase system, delivering higher than rated voltage.
- Incorrect wiring or line connections (~15%) Phase-to-neutral or phase-to-phase wiring is mislanded at the machine or panel, resulting in overvoltage.
- Control board voltage-sensing fault (~5%) The control board or voltage-sensing circuit misreports normal supply voltage as too high.
Quick Diagnosis
Answer these to narrow it down fast.
Does the error log in the controller show code E5?
No: The live EE display may represent a different fault code. Consult the service manual to decode the actual stored error.
Is the measured voltage at the machine's supply terminals above the nameplate range (typically above 127 V for 115 V units)?
No: Voltage is normal. Inspect the control board and voltage-sensing circuit for a false-trigger fault.
After restoring correct voltage, does the EE display clear when you cycle power?
No: The fault persists. Check the control board, wiring harness, and voltage-sensing components for damage or drift.
Step-by-Step Fix
- Access the error log on the controller to confirm that the stored fault code is E5, because the live display shows only EE for most errors.
- Measure incoming voltage at the machine’s supply terminals using a multimeter while the compressor is running and compare the reading to the nameplate voltage and acceptable range (for example, 104–127 V on some 115 V models).
- Trace the supply upstream if voltage is high. Check the branch circuit, panel wiring, and transformer. Verify that the machine is not connected to a high leg or incorrect phase on a split-phase or three-phase system.
- Verify phase-to-neutral and phase-to-phase wiring at the machine and panel. Correct any mislanding of conductors that delivers higher than rated voltage.
- Restore correct voltage and cycle power to the machine. The E5 high-voltage alarm is an automatic-reset error and should clear once voltage returns to the acceptable range.
- Inspect the control board and voltage-sensing circuit if voltage is normal but the fault persists. Look for damaged components, loose connectors, or drift in the sensing circuit.
- Monitor the machine after repair to confirm stable voltage and no recurrence of the EE(E5) alarm.
Parts Often Needed
| Part | Notes |
|---|---|
| Main control board | Amazon | Only if voltage-sensing circuit is faulty and voltage supply is confirmed correct. |
| Wiring harness or connectors | Amazon | Replace if damaged or corroded at the supply terminals or control board. |
When to Call a Pro
Call a qualified commercial refrigeration technician for any Hoshizaki EE(E5) error. Diagnosing high-voltage faults requires measuring live AC voltage under load, tracing panel and transformer wiring, and verifying correct phase connections on split-phase or three-phase supplies. Misdiagnosis can result in repeated nuisance trips or damage to the control board and compressor. If the cause is incorrect utility wiring or a transformer problem, you may also need an electrician to correct the upstream supply before the ice machine can run safely.
Rough cost: A pro service call runs about $150-350.