Microwave won't heat

Magnetrons generally should last about 2000 hours, but several factors can shorten that. If it's not OVER ten years old (from the purchase date or the date on the tag inside the unit) then the magnetron is still under warranty. From the owner's manual: "For the second through the tenth year from the date of original purchase "The magnetron tube, if the magnetron tube fails due to a defect in materials or workmanship. During this nine-year limited warranty, you will be responsible for any labor or in-home service costs. "For the above limited warranty: To avoid any trip charges, you must take the microwave oven to a General Electric Customer Care® servicer and pick it up following service. In-home service is also available, but you must pay for the service technician?s travel costs to your home." GE Customer Service is here, and you can verify the warranty status and find your nearest authorized servicer. If you're sure the magnetron's bad, it's still under warranty, and you or a friend are handy, they will
send you the magnetron to do it yourself. Call them at 888-239-6832. Be persistent. You may have to speak with a supervisor. It does sound like the magnetron overheated and the magnetron's thermostat opened until it cooled down. An overheating magnetron can be due to:

operating oven without cover(s) in place
wrong magnetron installed in oven
an old or otherwise failing magnetron
cracked magnetron magnet
improper power line voltage (should be 110-125VAC)
foods low in moisture (popcorn & bacon, e.g. - add 1/2 cup of water in rear oven)
failed or inoperable cooling fan or hood vent exhaust fan
deteriorating foam weatherstripping seals in air ducts or on outside cover
blocked air vents (dust, animal nest debris, insufficient free air space behind & around oven, etc.)
clogged or greasy charcoal filter or grease filter
blocked duct in hood vent exhaustSince yours is a counter top model, there are less of those factors to worry about. When you hit Start to
microwave, do the inside light, cooling fan, and turntable all come on?

Any unusual noises? Is
it louder or quieter than usual?
We have a sound clip of what a microwave should sound like when the cooling fan and high voltage section are operating here. You can find
helpful exploded view diagrams and order parts if needed by entering your full
model number from the tag on the oven here.
Let us know what you find out or decide. Magnetrons generally should last about 2000 hours, but several factors can shorten that. If it's not OVER ten years old (from the purchase date or the date on the tag inside the unit) then the magnetron is still under warranty. From the owner's manual: "For the second through the tenth year from the date of original purchase "The magnetron tube, if the magnetron tube fails due to a defect in materials or workmanship. During this nine-year limited warranty, you will be responsible for any labor or in-home service costs. "For the above limited warranty: To avoid any trip charges, you must take the microwave oven to a General Electric Customer Care® servicer and pick it up following service. In-home service is also available, but you must pay for the service technician?s travel costs to your home." GE Customer Service is here, and you can verify the warranty status and find your nearest authorized servicer. If you're sure the magnetron's bad, it's still under warranty, and you or a friend are handy, they will send you the magnetron to do it yourself. Call them at 888-239-6832. Be persistent. You may have to speak with a supervisor. It does sound like the magnetron overheated and the magnetron's thermostat opened until it cooled down. An overheating magnetron can be due to: operating oven without cover(s) in place wrong magnetron installed in oven an old or otherwise failing magnetron cracked magnetron magnet improper power line voltage (should be 110-125VAC) foods low in moisture (popcorn & bacon, e.g. - add 1/2 cup of water in rear oven) failed or inoperable cooling fan or hood vent exhaust fan deteriorating foam weatherstripping seals in air ducts or on outside cover blocked air vents (dust, animal nest debris, insufficient free air space behind & around oven, etc.) clogged or greasy charcoal filter or grease filter blocked duct in hood vent exhaustSince yours is a counter top model, there are less of those factors to worry about. When you hit Start to microwave, do the inside light, cooling fan, and turntable all come on? Any unusual noises? Is it louder or quieter than usual? We have a sound clip of what a microwave should sound like when the cooling fan and high voltage section are operating here. You can find helpful exploded view diagrams and order parts if needed by entering your full model number from the tag on the oven here. Let us know what you find out or decide.