What F3 means on your Dacor oven (dacor oven f3)
Dacor oven f3 means the Classic ERC board has measured a resistance on the oven temperature sensor circuit that is too low to be a real reading — in other words, the sensor or its wiring has shorted. The RTD (resistance temperature detector) probe mounted in the cavity back wall reports temperature as a changing resistance, and a short collapses that reading toward zero regardless of the actual cavity temperature. Because the ERC can no longer trust the sensor, it locks out heating on this Legacy Dacor (pre-2016) wall oven rather than guess at the real temperature.

Symptoms
The list below is how F3 announces itself on a Dacor oven, and how it differs from the oven problems people confuse it with.
- F3 appears on the display and the oven will not begin or continue heating.
- The problem can appear the moment you select a bake or broil temperature.
- The sensor probe visible on the back cavity wall may show scorching, a cracked tip, or discoloration.
- F3 sometimes follows a heavy oven-cleaning cycle where high heat has stressed the probe or its wiring.
- The problem can be intermittent at first, clearing after a cool-down and returning once the oven heats again.
Common causes
More than one thing can produce F3 on an oven, so the causes below are ordered by how often they turn out to be responsible on a Dacor oven.
- Failed RTD probe — the sensor element inside the probe has shorted internally, often from age or repeated high-heat cycling.
- Shorted sensor wiring — the two-wire harness between the probe and the ERC has chafed against a metal surface and shorted.
- Corroded connector — moisture or grease at the sensor plug has bridged the two terminals.
- Probe contact with an oven wall or rack — physical contact between the probe tip and cavity metal can mimic a short.
- ERC input problem — less commonly, the board’s sensor-reading circuit itself has degraded.
Troubleshooting steps you can try
An owner can safely attempt everything below on an oven, and everything beyond it on a Dacor oven is a technician’s job, with no shame in stopping early.
- With the oven off and cool, look for the sensor probe on the rear cavity wall and check it is not touching a rack, wall, or foil.
- Inspect the probe tip for visible scorching, cracking, or a melted-looking surface.
- Power-cycle the oven at the breaker and re-check whether F3 returns as soon as a cook cycle is selected.
- Avoid running a self-clean cycle while F3 is present, since the high heat can worsen a marginal sensor or wiring failure.
- If F3 clears temporarily after cooling and returns once hot, treat it as a genuine sensor failure rather than a nuisance code.
Parts a technician may replace
The parts most often in question on an oven here are the oven temperature sensor (rtd probe), sensor wiring harness, and electronic range control board. Which one has actually failed on your Dacor oven is settled by measurement, and nothing is ordered for the oven before that.
When to call a technician
F3 nearly always means the RTD probe or its harness needs testing with a meter and likely replacement — this is straightforward technician work once the oven is confirmed unsafe to run in the meantime. At Medium severity the oven is not in danger, though a F3 that keeps coming back on an oven is telling you something. We answer to you and not to Dacor, we fit genuine parts to your oven, and we warrant that labor for 30 days.
Related help and Dacor resources
Once the F3 condition has outlasted the owner-level checks, the oven is a service call: book one, or read the other oven problem pages. www.dacor.com holds the oven data sheet.