Hoshizaki E3/EE Error — What It Means
The E3 error code (often displayed as EE on the control panel until you check the error log to reveal the specific number) indicates a Long Freeze Cycle on Hoshizaki ice machines. The system monitors water level via float switches. When water fills the evaporator, the floats rise. As the water freezes into ice, the water level drops and the floats should descend. The E3 error triggers when the floats remain in the up position for too long, typically exceeding a safety limit of 80 to 100 seconds. This indicates the machine is not freezing the water as expected.
On some models like the FM-300, a similar E3 code can sometimes indicate a defrost sensor fault, but for standard commercial Hoshizaki ice makers, the primary definition is Long Freeze Cycle. The fault means the machine is simulating a condition where water never freezes or the level never drops, which prevents the harvest cycle from starting.
Before You Replace Anything
Technicians sometimes replace the control board or refrigerant system first. Clean and test the float switch assembly for free before replacing any expensive components, as debris or scale in the float mechanism is the most common cause.
Common Causes
- Stuck or clogged float switches (~40%) Scale, debris, or dirt clogging the float mechanism or the small tubes connected to it prevents the float from dropping, so the machine never detects that the water has frozen.
- Leaking water inlet valve (~20%) The valve fails to close completely, constantly adding warm water and preventing the water level from dropping during the freeze cycle.
- Low refrigerant levels (~15%) Insufficient refrigerant prevents the water from freezing quickly, so the water level never drops and the floats stay up.
- Dirty evaporator plate (~10%) A buildup of dirt or scale on the evaporator reduces heat transfer efficiency and slows or prevents proper freezing.
- Hot gas valve stuck open (~10%) The HGV may be stuck open or malfunctioning, preventing the system from entering the proper cooling cycle and keeping the plate warm.
- Hot water supply (~5%) Hot water entering the unit from other lines (such as running past an oven) raises the water temperature and significantly slows the freeze.
Quick Diagnosis
Answer these to narrow it down fast.
Does the float switch move freely when you push it up and release it?
No: The float is stuck or clogged. Clean the float switch assembly and the small tubes attached to it, then test the machine again.
Does water continue to flow into the machine when you disconnect a wire from the inlet valve during the freeze cycle?
No: The inlet valve is functioning. The problem is likely refrigerant, the evaporator, or the hot gas valve. Call a refrigeration technician.
Is the evaporator plate cold to the touch a few minutes after the freeze cycle starts?
No: The plate is not cooling properly. Check for low refrigerant or a stuck-open hot gas valve. This requires a refrigeration technician.
Step-by-Step Fix
- Locate the float switch next to the water pump and pull the boot off to expose the mechanism and small tubes.
- Inspect for scale or debris inside the float chamber and on the tubes, and clean thoroughly with water and a soft brush.
- Manually test the float by pushing it up and releasing it to confirm it drops freely under its own weight.
- Disconnect one wire from the water inlet valve during the freeze cycle and observe whether water flow stops immediately.
- Check the evaporator plate for dirt or scale buildup and clean the surface if necessary to restore heat transfer.
- Measure the plate temperature at startup: if it stays room temperature in freeze mode, suspect low refrigerant; if it stays hot, suspect the hot gas valve.
- Test refrigerant charge by measuring temperature on both sides of the water valve during freeze: if the outlet is very cold but water does not freeze, refrigerant is likely low and requires a certified technician.
Parts Often Needed
| Part | Notes |
|---|---|
| Float switch assembly | Amazon | Verify your model number before ordering, as float designs vary by series. |
| Water inlet valve | Amazon | Choose the correct valve for your machine’s voltage and water connection size. |
| Hot gas valve (HGV) | Amazon | Consult your model’s service manual to confirm the correct replacement valve. |
When to Call a Pro
Call a professional refrigeration technician if cleaning the float switch and checking the water inlet valve do not resolve the E3 error. Low refrigerant, hot gas valve faults, and sealed-system issues require specialized tools, EPA certification for refrigerant handling, and diagnostic equipment to measure pressures and temperatures accurately. Attempting refrigerant work without proper training can damage the machine and void warranties. A technician will also check for electrical harness faults, control board issues, and calibrate the system after repairs.
Rough cost: A pro service call runs about $150-400.