Thermador Oven Error Code E320: How to Fix It

Q: What does Thermador oven error code E320 mean?

Error code E320 on a Thermador oven means the inverter board has detected an over current condition — it is drawing or passing more electrical current than it is designed to handle. This can be caused by a failing inverter board, a shorted heating element, damaged wiring, or a power surge.

Q: Can I still use my Thermador oven with an E320 error?

It is not recommended. The E320 error typically prevents the oven from operating normally as a safety measure. Attempting to force the oven to run with an active over current fault could damage additional components or create an electrical hazard.

Q: Will resetting my Thermador oven fix the E320 error?

A power cycle (turning off the circuit breaker for 5 minutes and restoring power) will fix E320 if it was caused by a temporary power fluctuation or a software glitch. However, if the error returns after the reset, there is an underlying hardware issue — such as a failed inverter board or shorted element — that requires diagnosis and repair.

Q: How much does it cost to replace a Thermador oven inverter board?

Inverter board replacement parts for Thermador ovens typically range from $100 to $350 depending on the model. If you hire a technician for the repair, total costs including labor can range from $250 to $600 or more. Getting a repair estimate before ordering parts is a good idea, especially for older ovens.

Q: Can a faulty heating element cause the Thermador E320 error?

Yes. A shorted heating element can draw excessive current through the inverter board, triggering the E320 over current fault. Testing both the bake and broil elements with a multimeter for shorts or open circuits is an important diagnostic step before replacing the inverter board itself.

Abstract

The Thermador oven error code E320 indicates an over current condition on the inverter board, meaning the board is drawing more electrical current than it should. This can be triggered by a failing inverter board, a short circuit in a connected component, or a power surge that disrupted normal operation. Left unaddressed, this error can prevent your oven from operating and may cause further damage to internal electronics.