Hoshizaki Refrigerator Error Code E01: Cabinet Thermistor Failed
E01 on a Hoshizaki Steelheart A-Series refrigerator or freezer means the cabinet thermistor has failed. The appliance keeps cycling on and off. Press the up button to silence the alarm and call a qualified service technician.
Medium: the appliance keeps cycling but without proper temperature feedback.
- Code
- E01
- Maker
- Hoshizaki
- Equipment
- Reach-in refrigerators
- Applies to
- Steelheart A-Series upright controller
What does Hoshizaki error code E01 mean?
The cabinet thermistor is the temperature sensor that tells the controller how warm the cabinet is, so the controller can start and stop the compressor. When that thermistor fails, the controller logs E01 and sounds the alarm, beeping for 10 seconds and resting for 50 seconds. The appliance does not simply stop. The manual says it cycles on and off with the cabinet thermistor logic, so cooling continues, but without a working cabinet sensor the controller is no longer following the true cabinet temperature. The result can be a cabinet that drifts warmer or colder than the setting. You can silence the alarm by pressing the up button, but silencing does not repair the sensor. The manual's single cause is the failed cabinet thermistor, and its action is to call a qualified service technician.
Affected models and control systems
Steelheart Upright A-Series: R1A and R2A refrigerators and F1A and F2A freezers, with the DT2A also named in the manual.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- E01 on the control display
- Alarm beeping for 10 seconds with a 50-second rest
- Cabinet temperature that wanders from the setting
- Compressor cycling on and off
Possible causes
Listed in Hoshizaki's documentation
- Failed cabinet thermistor
Other likely causes — what usually sits behind error code E01 on this control. A technician confirms which one it is before any part is replaced.
- A thermistor lead worn or pinched where it enters the cabinet
- Moisture or corrosion at the thermistor connector
- A control input that no longer reads a good thermistor
Safe checks before calling for service
- Press the up button to silence the alarm, as the manual says.
- Place a separate thermometer in the cabinet and watch the readings through the day.
- Move temperature-sensitive food if the cabinet drifts toward the warm side.
- Write down the model, the code and the thermometer readings for the service call.
How a technician diagnoses error code E01
- Read the code and confirm E01 is the only alarm, not paired with E02.
- Inspect the cabinet thermistor lead and connector.
- Measure thermistor resistance and compare it with the cabinet temperature.
- Check the connector and controller input if the thermistor is good.
- Replace the thermistor only after the measurement, and verify normal control.
- The thermistor connections sit behind panels near live controls.
- A resistance test needs a meter and the temperature-resistance values.
- While the sensor is failed, cabinet temperature has to be checked against food safety limits.
How error code E01 differs from similar codes
E01 is the cabinet thermistor, which keeps the appliance cycling; E02 is the defrost thermistor, which cycles it 5 minutes on and 5 minutes off.
Technical reference
- Maker documentation
- Hoshizaki owner support
- Edition
- Number 73237, issued 2-25-2019, revised 3-24-2022
- Models / control
- Steelheart A-Series upright controller
- Section
- Alarm Safeties, Alarm Signals table, pp. 30-31
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Hoshizaki reach-in refrigerator error codes
Will the refrigerator keep cooling with E01?
Often it keeps cycling, but the cabinet temperature is no longer reliably controlled. Check with a thermometer.
Does the up button fix it?
No. It silences the alarm, but the thermistor is still failed.
Is E01 the same as E02?
No. E01 is the cabinet thermistor and E02 is the defrost thermistor.
Need help with Hoshizaki error code E01?
A technician confirms the cause on site and gives you the price in writing before any work starts.