Cooktop High Severity
E4 Appliance Error Code

Monogram Cooktop E4 Error: Supply voltage out of range

The induction cooktop has measured an incoming supply voltage that is either too high or too low for safe inverter operation, and has shut down all induction zones to protect the power electronics.

~15%

DIY Fixable

From $200

Typical Repair Cost

1–3 hrs

Pro Repair Time

Quick Assessment

Answer to continue safely

Is it safe to keep using?

No. Operating an induction cooktop with out-of-range supply voltage risks damaging the inverter IGBTs and control electronics. Do not attempt to use the cooktop until voltage is confirmed stable.

Can I reset the code?

Yes. If the voltage event was transient, a breaker reset will clear E4. However, if the underlying voltage issue persists, the code will return under load and electrical inspection is necessary.

When to stop immediately?

Stop if you notice: The E4 code returns every time you run two or more zones simultaneously., The circuit breaker trips or feels warm to the touch..

Symptoms You May Notice

All induction zones shut down simultaneously

Every cooking zone loses power at the same moment, bringing all cooking to an immediate stop regardless of what power level was selected.

E4 code displayed across the control panel

The alphanumeric display shows E4 and the cooktop becomes unresponsive to all touch input until the fault is cleared or voltage is restored to normal.

Lights or other appliances in the home flicker or dim

Simultaneous voltage issues in other parts of the home suggest a broader supply problem such as a utility grid event or a tripped leg in the main panel.

Cooktop restarts on its own after a delay

If the voltage anomaly was brief, the cooktop may clear the E4 fault and attempt to resume normal operation after a short internal timeout, though zones will not return to their previous power level.

Possible Causes

1

Utility grid voltage sag or surge

A momentary drop or spike in the utility supply — caused by grid switching, load shedding, or nearby lightning — pushes the incoming voltage outside the cooktop's 196–264 V operating window.

DIY Possible
2

Loose or degraded terminal block connection

A high-resistance connection at the cooktop's terminal block or junction box increases effective impedance under load, causing a voltage drop that triggers E4 when high-power zones are active.

Requires Professional
3

Undersized or overloaded branch circuit

If the cooktop shares a circuit or the supply wiring is undersized, heavy induction loads pull the voltage below the minimum threshold, repeatedly triggering the E4 protection.

Requires Professional

Safe Checks You Can Do

These checks are safe for homeowners. No disassembly required. Do not remove panels or access internal components.
  1. 1

    Check other appliances for simultaneous issues

    Observe whether other hardwired appliances or lights in the kitchen show signs of low or erratic voltage at the same time the E4 appears. This helps determine whether the fault is within the cooktop or a supply-side problem.

    A plug-in voltage monitor on a nearby outlet will confirm grid voltage in real time.

  2. 2

    Inspect the circuit breaker for the cooktop

    Locate the dedicated cooktop breaker in the main panel. Check whether it has tripped to the middle position. Reset it fully off then on. If it trips again immediately, stop and call an electrician.

    Monogram ZHU induction cooktops typically require a dedicated 240 V, 40–50 A double-pole breaker.

  3. 3

    Perform a timed power reset

    If no wiring fault is suspected, switch the breaker off for 60 seconds and restore. Attempt to use the cooktop at low-to-medium power levels and observe whether E4 returns under load.

    Starting at lower power levels reduces the current draw that could expose a marginal voltage issue.

When to Call a Professional

Contact a qualified technician if:

  • Supply voltage measured at the terminal block is outside 196–264 V under load.
  • The dedicated circuit wiring or breaker does not meet the cooktop's rated amperage.
  • E4 recurs consistently and no utility grid event has been reported in the area.

Need Professional Help?

Find qualified technicians in your area for proper diagnostics and repair.

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