We purchased a GE combination convection oven and microwave (Model # PT970b0M1BB, Serial # MM6135840). The convection oven has never worked right, and after 4 service calls it has still not been repaired. The first time they came out, they said there was nothing wrong. The second time they said it was the temperature sensor and/or the control board, but they didn't have the parts. The 3rd time they replaced the parts, but the oven still wasn't working after the repair. The 4th time they said it was the lower burner, and they... read full review »