Thermistor
Common temperature-sensing fault part. Confirm resistance range and connector.
Manitowoc Ice Machine Error Code 6 — What It Means
Error Code 6 on a Manitowoc ice machine indicates a water fill timeout — the machine attempted to fill the water trough but didn’t reach the required level within the allotted time. The control board times the fill cycle; if the float switch or probe doesn’t confirm a full trough, it faults out and shuts down ice production.
Common Causes
- Clogged water inlet valve — Mineral deposits or debris block flow, reducing fill rate below what the timer allows.
- Faulty water level probe or float switch — Sensor reports trough is empty even when it’s filling correctly; the board never gets the “full” signal.
- Low water pressure — Supply pressure below 20 PSI causes slow fill. Check the line.
- Kinked or frozen supply line — Physical restriction upstream of the inlet valve limits flow.
Step-by-Step Fix
- Check incoming water pressure — Connect a gauge to the supply line. Manitowoc requires 20–80 PSI. Below 20 PSI, the fill will timeout.
- Inspect and clean the water inlet valve — Turn off water supply, disconnect the valve, and flush it. If the screen is scaled, soak in white vinegar or replace the valve.
- Test the water level probe/float switch — With power off, remove the probe from the trough and test continuity. A faulty probe will show open or erratic. Replace if bad.
- Inspect the supply line — Trace the water line for kinks, closed shutoffs, or freeze-ups (common in cold rooms). Straighten or thaw as needed.
- Reset the system — After repairs, press and hold the Off button for 3 seconds, then press On to restart. Monitor the fill cycle to confirm it completes without faulting.
Parts Often Needed
| Part | Notes |
|---|---|
| Water inlet valve | Most common fix; replace if flow is restricted |
| Water level probe/float switch | Replace if it’s not signaling full trough correctly |
| Water supply line | Replace if kinked or cracked |
Technician Tips
When diagnosing commercial refrigeration faults, start with the controller’s alarm history. Most digital controllers (Dixell, Carel, Eliwell) store the last 5-10 alarms with timestamps. An E1 alarm that appears consistently every few hours suggests a sensor going bad — the resistance value drifts until it’s out of range. An intermittent HI/LO alarm that appears only during hot afternoons suggests a condenser issue, not a sensor fault.
Prevention: Schedule quarterly condenser coil cleaning. Dirty coils are the #1 cause of high-head-pressure faults and compressor overheating in commercial refrigeration. Use a soft brush and compressed air — never a pressure washer on the coil fins.
Need Replacement Parts?
Before ordering, match the ice-machine part to the model number, electrical rating, and failure symptom. Check current prices on Amazon - prices and availability change frequently.
When to Call a Pro
If water pressure is good and the valve and probe check out, the issue may be a failed control board — board replacement requires a trained technician to program and verify the unit properly.