Written by
Lena Hartwell Appliance Care EditorPublished October 27, 2026
VERIFIED
Error codeU20 / L20
ApplianceWall Oven
Which oven and which fault
An oven that reports OVER TEMP with U20 is the upper or single cavity; with L20 it is the lower one. Dacor defines the fault as the middle of the oven cell holding above 610°F for 2 minutes while cooking.
Effects on use
The door lock engages and then releases once the cavity reaches 375°F.
Cooking is possible again after temperatures recover.
Cleaning is blocked until the error has been cleared.
Owner action
A single step is listed: call for service.
Three sources the manual names
Software versions that are not compatible across the micros, which a technician confirms are compatible.
A shifted calibration of the oven or mode. A thermocouple placed at the cell center during the mode should show an average within 10°F of target.
Heating elements stuck on. A technician runs a cooking mode after preheat and watches whether the elements cycle.
Covered ovens
Dacor Renaissance EOR and MOR wall ovens, along with the 27 and 30 inch ovens in the Dacor Wall Oven Service Manual.
U22: a temperature amplifier failure between the two probes
Dacor wall oven repair in San Francisco and nearby
Seeing U20 or L20? Call (415) 687-5926 and ask about Dacor wall oven repair in the Bay Area. Note the exact code, whether it was the upper or lower oven, and the model number.
Model compatibility: Dacor reuses codes across series and model years, so U20 / L20 may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.
Plain language
What this code means
U20 (upper/single) or L20 (lower) means the cavity center exceeded 610 F for 2 minutes during cooking.
Important safety warning. Do not attempt repairs involving electrical components, gas, water lines, refrigerant or sealed systems. Unplug the appliance if it is safe to reach the outlet, and leave internal diagnostics to a qualified technician.
Seeing this code on your Dacor appliance?
Book a specialist visit for a clear estimate and approval before any repair.
You submit a request with your appliance model and symptom, we confirm an appointment window, and a technician performs an on-site diagnosis. You then receive a clear estimate and decide whether to proceed before any repair begins.
Yes. We provide an upfront estimate after diagnosis. No parts are ordered or installed until you approve the work, so there are no surprise charges.
Replacement parts are selected for the exact model and confirmed with you before ordering or installation.
Service areas are listed on the Locations page. Contact us with your ZIP code to confirm current coverage for your address.
Ready to get your Dacor appliance working again?
Book a repair online or call us — clear estimates and approval before any repair work begins.
