What U20 / L20 Means
On Renaissance EOR/MOR wall ovens, codes starting with U belong to the upper (or single) oven and codes starting with L to the lower oven. U20 or L20 means that oven’s center temperature went above the cooking limit, which Dacor’s service guide sets at 610°F.
Common Causes of U20 / L20
- Relay on the relay board stuck closed so an element stays on
- RTD sensor reading low so the control over-heats the cavity
- Broil or convection element miswired after an earlier repair
🔧 One Safe Check You Can Try
Turn the oven off and let it cool with the door shut. Do not restart it to see what happens; an oven that overshoots 610°F in a cooking mode has a heating control problem.
⚠ Why You Shouldn't Go Further Than That
- A stuck relay keeps powering an element regardless of the control; it is live 240-volt work.
- This code is stored in the oven’s memory, and a technician can read the history to see how often it has happened.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.