Manitowoc Indigo Ice Machine Error Code E01: Long Freeze Cycle
E01 on a Manitowoc Indigo cuber that is not the NXT touch-display type is written to the event log when freeze cycles keep running long. After six freeze cycles in a row reach 60 minutes, the control board shuts the machine down and flashes the SL#1 light. Check the water supply valve and clear the area around the condenser first.
Medium: the machine shuts itself down after repeated long freezes and stays stopped.
- Code
- E01
- Maker
- Manitowoc
- Equipment
- Ice machines
- Applies to
- Indigo series (non-NXT) control board, Event Log (Service menu > Event Log > View ELog)
What does Manitowoc error code E01 mean?
A normal freeze cycle ends when ice on the evaporator reaches the right thickness. The control board times each freeze. If a freeze cycle runs to 60 minutes, the board logs it, and after six in a row it concludes the machine is not making ice properly and shuts it down, flashing the SL#1 light on the board. Staff see an icemaker that has stopped with an empty or shrinking bin. The record lives in the Event Log in the Service menu, under View ELog. Long freezes have several possible causes: weak water flow, a dirty ice thickness probe, a hot kitchen or blocked condenser airflow, a refrigerant charge problem or a scaled evaporator plate. The log tells a technician that the problem developed over many cycles and that the cause is a slow restriction, not a sudden failure.
Affected models and control systems
Manitowoc Indigo series cubers with the non-NXT control board, which records events in the Service menu under Event Log, View ELog. Other control generations use different codes.
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
- Icemaker stopped with the bin empty or low
- SL#1 light flashing on the board
- Ice slow to build before the shutdown
- Cubes thin or irregular beforehand
Possible causes
Listed in Manitowoc's documentation
- Water supply, filter and inlet valve flow
- Ice thickness probe cleanliness and gap
- Condenser airflow and kitchen air temperature
- Refrigerant charge and expansion valve behavior
- Scale on the evaporator plate
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 water filter that is partly clogged
- A condenser coated in grease and dust
- Kitchen air near the top of the machine's rated range
- A probe covered in mineral film
Safe checks before calling for service
- Check that the water supply valve to the machine is open and the line is not kinked.
- Look at the area around the condenser and clear anything stacked against it.
- Follow the cleaning and descaling schedule in the owner's manual if it is overdue.
- Leave the board and service menu to us, and call if the machine stays stopped.
How a technician diagnoses error code E01
- Read the Event Log through the Service menu and note how E01 is grouped.
- Verify water supply pressure, filter and inlet valve flow.
- Clean the ice thickness probe and check its gap.
- Check condenser airflow and ambient temperature, then refrigerant pressures.
- Inspect the evaporator for scale before replacing refrigeration parts.
- Checking refrigerant pressures needs gauges and EPA-certified handling. The board and compressor circuits run on live line voltage. A scaled evaporator needs a full cleaning procedure, not a quick wipe.
How error code E01 differs from similar codes
E02 is the matching log entry for long harvest cycles. E01 concerns freeze cycles.
Technical reference
- Document
- Indigo Series Technician's Handbook 000014794 5/17, "Event Log" p.87-91
- Maker documentation
- Manitowoc owner support
- Edition
- Part Number 000014794 5/17
- Models / control
- Indigo series (non-NXT) control board, Event Log (Service menu > Event Log > View ELog)
- Section
- Event Log: code list p. 87, Event Log Detail table pp. 88-91 (Service menu > Event Log)
- 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 Manitowoc ice machine error codes
Can I restart the machine after E01?
You can try, but the cause must be found first or it will stop again.
Does descaling help?
If scale is the cause, yes. Follow the owner's manual schedule.
Is E01 the same as E02?
No. E01 is long freeze cycles. E02 is long harvest cycles.
Need help with Manitowoc error code E01?
A technician confirms the cause on site and gives you the price in writing before any work starts.