KitchenAid Architect II KHHC2090S Stainless Steel 1200 Watts Convection / Microwave Oven. Microwave quit heating. Inverter and magnetron replaced by the repairman. Still no heat but the magnetron gets smoking hot in a matter of seconds. Thanks.

You probably fried the magnetron(it actually makes the microwaves that do the cooking). I bet you will find the magnet is broken(from excessive heat). There should be a diagnostic guide sheet somewhere inside the housing(due to running production changes,this is a guide for the pros to test the power supply,magnetron,etc with an ohmmeter to determine which is defective.

A loud humming noise in microwave mode will usually be a shorted high voltage diode or bad magnetron.

It looks like that answer is on page 33 of your owner's manual.

If for some reason you don't still have yours, you can download it, your installation instructions, and parts lists here.

You can order parts here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Make sure that the program controller is working if not check power - step down supply, the pads are responding- if not faulty pads- or the door switches, if the switch contact are not good then it will not trigger the processor to switch on the waveguides. If the lights or fan work without any display or action of program being triggered to start then it can be a possible fault on the main board or the processor. Sometimes insect secretion can short the board and display panel and so the processor can work in such an erratic manner. If so clean,solder and reset the board.Now identify the parts by clicking this link: http://www.espares.co.uk/advice/microwave/a/5/141/identifying-microwave-parts.html If there is no heating please do not switch on unless you have confirmed the fault. It is possible that the Magnetron is faulty, the temperature cut off is faulty or the main capacitor is short. It is also quite possible that insect can get into the oven and create soft spots. When you switch on these will create a short and make the voltage jump and in the long run damage the magnetron.
So Remove cover after disconnecting , check for dirt/moisture in the cabin, if so wipe clean and dry, check the magnetron and area clean and use an jet air to clean off. Check the wave guide covers, if food had deposited
then it must be checked or replaced.See link: http://www.espares.co.uk/advice/microwave/a/5/1146/how-to-replace-a-microwave-guide-cover.html
Now keeping clear of the microwave, switch on, use a cup of water inside to test.
If you notice any sparks shut off as the magnetron or the main HT capacitor can be faulty. replace with same type.

Hi,
Here is a tip that will help you to figure out what is wrong with yourMicrowave Oven....

Microwave Oven Basic Troubleshooting Tips

heatman101 ,/./'

';\]

you can buy that part online kitchen aid.

It's hard to say without knowing the full model number.

So please include that in a new post so we can help you.

The microwaves are produced by a MAGNETRON. Everything else can work, but if that does not, then there is no heat added to the food. Unfortunately it is the most expensive part of the microwave and has nothing you can really work on.

Hope this helps.

And why am I not surprised?
I expect it is full of moisture.

eletrical problem cheek ur plug point try another point or loose connect ur eletrical