What does EE (log code EC) mean on a Hoshizaki IM-series square cuber?

Short answer: Evaporator (cube control) thermistor error. If your Hoshizaki IM-series square cuber (IM-500SAA and similar) is showing EE (log code EC), the controller has logged a specific, documented condition. This page covers what it means, what causes it, what you can safely fix yourself, and when — and why — it takes a technician.

What exactly is the machine telling you?

The evaporator thermistor circuit read open or shorted for 2 seconds and the unit stopped. Remedy is thermistor replacement.

Which machines show this?

Hoshizaki's IM-series square cubers (the IM-500SAA and its siblings) make the clear, square cubes bars prize — and unlike the KM crescent cubers, they have a 7-segment display that shows real codes. The display logic takes one minute to learn: E1 and E2 display directly (freeze and harvest backup timers), while every other fault shows as a generic EE with the true code stored in the error log for a technician to read. So if your IM shows EE, the display has told you something is wrong but not what — note any pattern in the machine's behavior (stopping mid-cycle, water tank movement) for the service call, and don't burn resets trying to make EE explain itself.

What causes it?

• The evaporator (cube control) thermistor reading open or shorted
• A damaged sensor wire
• A failed thermistor

Can you fix it yourself?

One power-cycle to rule out a transient reading. The sensor itself is a service item.

Step by step — what to try, in order:

1. Power-cycle once to rule out a transient fault

What to check before you call

• One power-cycle — Hoshizaki's listed first step for EC. It rules out a transient open or short reading.
• Whether EC returns after the reset — A persistent EC means the evaporator thermistor must be replaced professionally. Further resets won't change a failed sensor or damaged wire.
• Note that the display showed EE — On IM machines only E1 and E2 display directly. EC shows as a generic EE, with the true code stored in the error log for a technician to read.
• Leave the panels closed — Replacement includes verifying the new sensor reads true against the resistance chart, which is meter work for a technician.

When do you need a technician — and why?

The evaporator thermistor is how the board knows what the ice is doing; replacement includes verifying the new sensor reads true against the resistance chart — meter work by definition.

Parts a technician may look at

Based on the causes listed for this code (not a parts order — a tech confirms first):

• Evaporator (cube control) thermistor
• Sensor wire

What might it cost?

Typically a service call plus a modest part. When a technician is needed, this is usually a diagnostic visit plus a sensor, switch, valve, or similar small component. A rough, hedged range is a few hundred dollars in total — often in the $200–$500 band — but parts prices and labor rates vary a lot by model and area. Get a quote.

These are rough, typical ranges, not quotes; we don't have pricing data for your area or your exact model.

If it does come to a service call and you're in Nashville, TN or Birmingham, AL, we maintain independently compiled lists of local companies that service commercial ice machines — real businesses with verified contact information, none of whom paid to be listed.

Related questions

What does EE (log code EC) mean on a Hoshizaki IM-series square cuber (IM-500SAA and similar)?

Evaporator (cube control) thermistor error. The evaporator thermistor circuit read open or shorted for 2 seconds and the unit stopped. Remedy is thermistor replacement.

Can I fix EE (log code EC) on a Hoshizaki IM-series square cuber (IM-500SAA and similar) myself?

One power-cycle to rule out a transient reading. The sensor itself is a service item.

When does EE (log code EC) on a Hoshizaki IM-series square cuber (IM-500SAA and similar) need a technician?

The evaporator thermistor is how the board knows what the ice is doing; replacement includes verifying the new sensor reads true against the resistance chart — meter work by definition. A persistent EC means the evaporator thermistor must be replaced professionally.

What does EE with log code EC mean on a Hoshizaki IM?

The evaporator (cube control) thermistor circuit read open or shorted for 2 seconds, and the unit stopped. Hoshizaki's remedy is thermistor replacement.

Why does the evaporator thermistor matter?

It is how the control board knows what the ice is doing. Without a true reading, the board can't run the cycle, so the unit stops.

How is EC different from EE with log code E9?

Both display as EE and both are open-or-short sensor readings. EC is the evaporator (cube control) thermistor. E9 is the condenser thermistor, and it applies only to IM models equipped with one (not the IM-500SAA). Hoshizaki's remedy for either persistent code is thermistor replacement.

How is EC different from EE with log code E5?

EC means the evaporator thermistor reads open or shorted. E5 means the evaporator thermistor detected a sustained, abnormally high temperature. A shorted thermistor reading falsely high is one of the listed causes of E5, alongside harvest problems and hot water feeding the machine.

Source: IM-500SAA_serv_LTR.pdf (hoshizakiamerica.com)