Powers but no heat. Everything else functions

Chances are you have a bad secondary / cook relay on the control circuit board. The relay can be replaced. See details here.

The magnetron may be defective. You can replace the magnetron, there is no other possibility.

If the microwave oven is 7 years old or less, the cause is a bad magnetron, or the inverter board is malfunctioning, due to cost in parts and labour cheaper to replace.

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

Microwave Oven Basic Troubleshooting Tips

heatman101

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

Microwave Oven Basic Troubleshooting Tips

heatman101

Generally speaking, charcoal filters should be changed and grease filters should be cleaned about every six months, or whenever you notice they are getting dirty & clogged. Yours will likely have one or the other - probably not both - depending on whether it's vented or it recirculates.

A clogged filter will cause the supply of cooling air flow to be lessened, allowing the magnetron to overheat. It only takes one severe overheating to damage or destroy a magnetron.

One common way for a magnetron to fail is that its heating power is less and less, then it just stops heating.

Magnetron's will usually have a warranty of 5-9 years, but you'd still have to pay the installation labor.

You can save a $75-90 home visit by removing the oven form the wall and taking it to a local Whirlpool-authorized warranty servicer.

The date of manufacture will be on the model tag in the unit, and the warranty terms will be in the owner's manual. Many manufacturers will use the serial number and date of manufacture to validate the warranty in lieu of a sales receipt.

You can download Whirlpool owner's manuals and installation instructions here.

You can find helpful exploded view diagrams and order parts and accessories by entering your full model number here.

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

Generally the magnetron (the part that heats the food) is the cause if everything else still works and it only works once in a while, possibly a short, but not as likely. Unfortunately replacing the magnetron is barely cheaper than buying a new microwave though you can check out repairclinic.com to decide whether you want to attempt replacing the part.

Let me know how this works out for you.
Benjamin

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

Basic Microwave Oven TroubleshootingTips

heatman101[p]][p

When the microwave won't heat, but you hear a loud buzz, you usually have a defective power diode, high-voltage capacitor, or magnetron. We recommend that you consult with a qualified appliance repair technician for help in determining the problem and deciding what to do about it.
thanks and please do not forget to accept the solution

Hi I've been out of the microwave repair business for a few years now, but the technology has remained virtually the same as far as I know. You obviously have some knowledge of them, as you know about the safety switches in the door. Microwave ovens are actually a very simple device, to test it, put a coffee cup of water inside, and set the unit on high for one minute. A second or two after you hit the start button, you should hear a fairly loud "bong" noise, and a hum that continues untill the time runs out. That noise is the magnetron starting up, and if that noise does not happen, then the magnetron or related circuitry is probably bad. NEVER open up the oven, as the magnetron may be charged, and must be discharged by a technician. If the sounds that I described are present, then the water should be boiling or close to it in one minute, if not,then something I've never seen has gone wrong. Assuming you had a year warranty on it, I know from experience that if you contact Goldstar customer service by phone, or letter, they will often extend their warranty a month or so to keep happy customers. Its worth a try. Hope this helps you out. P.S. Never operate a microwave without something inside (Non metalic)