We learned our lesson with Frigidaire. The convection oven took 90 minutes at 400 to bake a potato...Frigidaire insisted the tech replace the transmitter tube to fix it. I never did figure out their logic (nor did it fix the problem) as the microwave doesn't run in convection mode.
You'll find a Sharp unit in our kitchen now.
Keith, I looked in the pantry closet for reference page supplied by Heartland and found no listing for the Frigidaire Microwave oven, so I called Heartland they told me to call Frigidaire about the problem, so I was connected to a automated phone line and getting so annoyed not being able to speak to a real person, I went online to appliance repair.com and figured out that more than likely the control board went bad. The cost was $150.00 plus shipping. My microwave had never been used not one time, a little over a year old. I figured that by the time I spent the money to repair it and still no warranty I would be better off to replace it. I went to Sears and bought a Kenmore Elite Microwave/convection and trashed the Frigidaire, thank god that is the only FRIGIDAIRE product in the RV.