U-Line UHWC524 E3 (Class Series): Thermistor 3 Open Entry

E3 (Class Series) at a glance

Code

E3 (Class Series)

Appliance

U-Line wine refrigerator

Applies to

U-Line 5 Class UHWC524 wine cooler (error log)

Type

Needs attention soon

Can you clear it yourself?

Sometimes, after the safe checks below

Most likely cause

Thermistor 3 itself reads open

What you may notice with E3 (Class Series)

• E3 appears among the entries of the error log
• The temperature in the cabinet may drift
• The doors report nothing, so they are not the cause

How the wine refrigerator detects E3 (Class Series)

Thermistor 3 is the third temperature sensor in the UHWC524, and its job is to let the control know the temperature in its part of the cabinet. The control relies on a complete circuit to hear from it.

When the circuit opens, the signal stops, and the control makes an entry for E3 in its error log. That makes it the open condition of the third sensor, whereas E7 stands for the same sensor shorted. A break could be inside the sensor, in its wiring or at a connector, and the log entry alone does not say which. Because the control loses a temperature input, it may not regulate that area as well as it normally would until the circuit is repaired.

Likely causes of E3 (Class Series)

• Thermistor 3 itself reads open
• A break or crush damage along the sensor wiring
• A connector is loose and has lost its grip

Can you keep using the wine refrigerator with E3 (Class Series)?

You can run it for a short time, but pay attention to the temperature. With Thermistor 3 unreadable, the control may not hold its zone at the setting. A separate thermometer gives the real number, and checking it several times a day is sensible. If it climbs, move your wine to a cooler place and leave the cooler switched off until it has been examined.

What you can safely check

1. Stop the cooler at the plug for about a minute, then restart it.
2. Place a thermometer inside and watch the number it shows.
3. Keep the floor behind the cooler dry.
4. Leave the back panel of the cabinet closed.
5. If E3 shows again, call us.

What our technician does for E3 (Class Series)

• Test Thermistor 3 for an open circuit
• Check the sensor wiring and connector one at a time
• Replace the sensor or repair the wiring, then verify the log

How to keep E3 (Class Series) from coming back

• Keep the space behind the cooler dry and free of clutter.
• Avoid knocking or pulling the cooler while moving it for cleaning.
• Look at the display after storms or surges in case a new entry appears.

Technical reference

Code

E3 (Class Series)

Appliance

U-Line wine refrigerator

Control family

U-Line 5 Class UHWC524 wine cooler (error log)

Maker documentation

U-Line owner manuals and support

Checked

November 2026

Code meanings come from the maker’s documentation and our own repair work; we do not reprint the maker’s document. Confirm the full model number before acting on a code. We are an independent repair company, not affiliated with U-Line Corporation.