Hussmann Display Refrigerator Error Code E2: Evaporator Sensor Failed
E2 means the evaporator sensor has failed or is disconnected. The manual says to check the display for E1 or E2 and call service immediately. It does not describe what the case does while E2 is active.
High: the manual says to call service immediately, and the evaporator is no longer being monitored.
- Code
- E2
- Maker
- Hussmann
- Equipment
- Display cases
- Applies to
- Safe-NET III controller, LTH low-temperature merchandisers (same E1/E2 text in ISF/ISM manual P/N 0515154_G)
What does Hussmann error code E2 mean?
The Safe-NET III controller in an LTH low-temperature merchandiser reads a sensor on the evaporator, separate from the case temperature sensor. That sensor reports on the coil, which matters for defrost and for protecting the evaporator. When the evaporator sensor fails or is disconnected, the controller no longer has a coil reading and shows E2 on the temperature display with the red alarm LED flashing. The manual's wording is short: the evaporator sensor has failed or is disconnected. It gives no detail about the effect on cooling, so unlike E1 it does not state that refrigeration runs continuously. Its action is to check the display for E1 or E2 and call service immediately. It gives no duty-cycle workaround for E2. The case temperature may still look normal on the display, which is one reason an E2 can go unnoticed.
Affected models and control systems
Safe-NET III controller on Hussmann LTH low-temperature merchandisers. The manual (Alarms and Codes, pages 3-2 to 3-3) notes the same E1 and E2 text appears in the ISF/ISM manual, P/N 0515154_G.
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
- E2 on the temperature display
- Red alarm LED flashing
- Case temperature looking normal while the coil is not being monitored
- Ice building on the evaporator over time
Possible causes
Listed in Hussmann's documentation
- Evaporator sensor failed or disconnected
Other likely causes — what usually sits behind error code E2 on this control. A technician confirms which one it is before any part is replaced.
- Evaporator sensor lead loosened or pulled during cleaning or service
- Ice damaging the sensor lead where it runs along the coil
- Moisture in the sensor connector in a cold, damp case
- Controller input not reading a good evaporator sensor
Safe checks before calling for service
- Note E2 and the flashing red LED on the display, and check for E1 as well.
- Call for service immediately, as the manual directs.
- Check the case temperature with a thermometer to confirm the case is holding temperature.
- Look at the product and case floor for water or ice, and tell the technician what you saw.
How a technician diagnoses error code E2
- Read E2 and check whether E1 is also shown.
- Locate the evaporator sensor and inspect its lead and connector.
- Measure sensor resistance against its chart with the sensor disconnected.
- Check the controller input for a proper reading.
- Replace the sensor or lead, then confirm E2 clears and a defrost cycle behaves normally.
- The evaporator sensor is behind case panels with live heaters and fans.
- A meter and a sensor chart are needed to separate a sensor failure from a controller input problem.
- Ice on a coil without a working sensor needs to be cleared safely.
Technical reference
- Document
- LTH Low Temperature Merchandisers Installation & Operation Manual (Safe-NET III)
- Edition
- P/N 0506146_G, June 2015 (Revision G)
- Models / control
- Safe-NET III controller, LTH low-temperature merchandisers (same E1/E2 text in ISF/ISM manual P/N 0515154_G)
- Section
- Alarms and Codes, pp. 3-2 to 3-3
- 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 Hussmann display case error codes
Does the case stop cooling with E2?
The manual does not say. It only says to call service immediately.
Is E2 less urgent than E1?
The manual gives the same call-service-immediately instruction for both.
Is this a case temperature problem?
No. E2 concerns the evaporator sensor. A case temperature sensor problem shows as E1.
Need help with Hussmann error code E2?
A technician confirms the cause on site and gives you the price in writing before any work starts.