DaasYochid – “a device whose purpose is to perform a certain action cannot be considered a grama no matter the mechanism it uses. It would be a full fledged melachah.”
Except in situations such as a refrigerator or water cooler according to Rav Shlomo Zalman and Rav Moshe and numerous other g’dolei poskim who hold it is permitted even if the motor is off and opening the device will cause the motor to turn on; it is permissible and this includes an oven door according to Rav Moshe.