Bertazzoni REF18WCB/REF24WCB Codes E3 and E4: Upper Zone Frosting Probe Open or Shorted

What E3/E4 means

On Bertazzoni REF18WCB and REF24WCB built-in wine coolers, including the REF24WCBPNV and REF18WCBPLV, E3 and E4 refer to the frosting probe of the upper zone. E3 means the probe is open, and E4 means it is shorted. The buzzer gives three "tic" sounds, the code flashes every 10 seconds, and the on/off key silences it. A technician is needed. Only one of the two codes shows at a time.

Common causes of E3/E4

An upper zone frosting probe that has failed open (E3) or shorted (E4)
A damaged lead or loose plug at that probe
Frost or moisture around the probe
A control board input that cannot read the frosting probe

✓ One safe check you can try

1. Press the on/off key to stop the buzzer. 2. Look at the back of the upper zone for heavy frost. 3. Make sure bottles do not touch the rear wall. 4. Keep the door closed and check the temperature with a thermometer. 5. Tell us whether E3 or E4 is showing when you call.

! Why to stop there

The frosting probe sits at the cooling surface, and the surface is easy to damage.
Scraping frost with tools can puncture the cooling circuit.
Open and short readings look alike from outside, so a meter is needed to pick the right repair.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

→Same appliance

Other Wine Column codes

Upper or lower zone too warmBertazzoni Wine Column Message "Upper or Lower Zone Too Warm": Zone Above Setpoint Upper or lower zone too coldBertazzoni Wine Column Message "Upper or Lower Zone Too Cold": Wait Before Calling Check condenserBertazzoni Wine Column Message "Check Cond": Time to Clean the Condenser Door openBertazzoni Wine Column Message "Door open": Door Left Open Too Long E1/E2Bertazzoni REF18WCB/REF24WCB Codes E1 and E2: Upper Zone In-Cabinet Probe Open or Shorted E5/E6Bertazzoni REF18WCB/REF24WCB Codes E5 and E6: Middle Zone In-Cabinet Probe Open or Shorted E7/E8Bertazzoni REF18WCB/REF24WCB Codes E7 and E8: Middle Zone Frosting Probe Open or Shorted E11/E12Bertazzoni REF18WCB/REF24WCB Codes E11 and E12: Lower Zone Frosting Probe Open or Shorted

E3/E4E3/E4 questions

What does a frosting probe do?

It watches the cold surface of the upper zone for frost, helping the control decide when to clear it. If the probe cannot be read, defrost timing may suffer.

E3 and E4 are shown together. Which one do I have?

Only one shows at a time. E3 is an open circuit and E4 is a short. Tell us which you saw, since it helps us bring the right part.

Will the wine zone keep cooling?

The cabinet may continue to run, but without frost information the zone can drift. Watch the thermometer, and book a visit soon so the probe or wiring can be fixed.