Examined top oven unit set 350 let fully heat and cycle actual temp 330 calibrated cycle off 353.recovers 344 good let heat, found temp controller very erratic at times, normal then 30 degree swing, cycling on 360 off 375 then back to on 348 off 367, then dropping to 330 before recovering. Will order parts, bottom oven tested good. 1/14/19 Removed and replaced temp board and potentiometer in top left oven. tested. unit cycled on temp and at 325 and 350. Set unit to 400, unit at 425 and still heating. found contactor buzzing, contactor sticking. Removed power to unit and examined contactor. Contactor bad, will order and return. 1/16/19 Removed and replaced contactor and repaired over heated wiring, checked calibration, set 350, cycled off 349 back on 341 tested good.