During self-clean an LG wall oven heats far beyond any cooking temperature and locks its door so the cavity cannot be opened until it is safe. The lock is a motor-driven latch controlled by the oven's temperature sensor, and it does not release the moment the cycle timer reaches zero. Owners who expect the door to open with the beep, and find it still locked an hour later, often assume the latch has failed. Usually it has not.
How Long Is Normal
After the heating phase ends, the oven must cool to a temperature the control considers safe before the latch motor is told to release. In a well-insulated wall oven, especially a double, that cooling can take well over an hour, and the display shows the lock indicator throughout. Leave it alone during that time. Do not open the kitchen windows to hurry it and do not aim a fan at the door; the glass and the cavity are designed to cool at their own rate.
Do Not Force the Door
Pulling hard on a locked oven door bends the latch hook, strains the latch motor and can crack the door glass. If the oven is still hot inside, forcing the door also releases air that can burn you. A latch that has been bent by force will fail to lock on the next self-clean and will need replacing, which turns a wait into a repair.
If It Is Cold and Still Locked
Touch the door glass. If it is at room temperature and the lock indicator is still lit, the control has not sent the release. Switch the oven off at its breaker, because a wall oven has no plug to pull, leave it off for several minutes and restore power. On many models the latch motor cycles during start-up and the door releases. If an F code appears at the same time, note it exactly, because the codes for door-lock faults tell the technician whether the latch switch, the latch motor or the sensor is at issue.
When the Latch Has Failed
A door that remains locked after the oven is cold and the breaker has been reset has a latch motor or latch switch fault, or a temperature sensor telling the control the oven is still hot. Reaching the latch means removing the control panel or top trim of a hard-wired oven with the breaker off and confirmed dead, and that is technician work. Do not attempt to trip the latch through the door gap with a tool.
Before the Next Self-Clean
Remove the oven racks and any probe before starting the cycle, as the manual directs, because LG's racks are not designed to survive self-clean temperatures and a warped rack can foul the door. Wipe up heavy spills first; the cycle carbonises residue but a thick pool of grease produces heavy smoke and can flare. Keep children and pets away from the oven for the whole cycle and the cooling period, because the door glass gets hot enough to burn, and run the kitchen ventilation. If you ever see flames through the glass during self-clean, switch the oven off at the breaker, leave the door locked and call the fire department if the flames do not die within a minute.
Booking It
Say how long the oven has been cold, whether the breaker reset was tried, and any code displayed. Book an LG wall oven repair with the model number from the plate on the oven frame, which you can see with the door open, or from the installation documents if the door will not open at all.