It makes horrible sounds as it cooks.
As it cooks, your microwave should be relatively quiet, making no more then a gentle hum. If instead it becomes loud and makes grinding, buzzing, or rattling noises, something is amiss. First, check the turntable and fan blades.
Like many other devices, microwaves have a thermal fuse to keep the appliance from overheating. If this fuse is blown, the microwave won't power on. Microwaves also have a ceramic fuse. This is usually inside the rear panel, near the power cord.
Smoke, sparks, and burning odor are the primary signs that signal the last days of a microwave. Other problems like unexplained loud noise, prolonged or faster cooking, loose door hinge, and malfunctioning keypad are signs to invest in a new microwave.
To avoid replacing yours more than about once every 10 years—which is how long most manufacturers tell us they should last—you'll want to take care of it. Your microwave may not get as grimy as your oven, but even so, one of the best ways to keep it humming along is to keep it clean.
You can test if your microwave is heating properly by heating a cup of water in a microwave-safe dish for about 30 seconds. Carefully test the water to see if it has heated. If it isn't hot, repeat the process. If it still isn't hot after a few attempts, it is not heating properly.
Reasons: Control panel issues: A malfunctioning control panel can prevent the microwave from responding to your inputs. Fuse problems: Blown fuses can interrupt the power supply to the microwave. Power cord damage: A damaged or disconnected power cord can prevent the microwave from receiving power.
A high pitch or loud hum points to the magnetron or diode, while a rattling or buzzing sound from the rear of the microwave indicates the cooling fan is at fault. Before repairing a microwave, be aware that it can be very dangerous.
One of the most common issues with a malfunctioning Magnetron is the lack of heating. If your microwave is running but not producing heat, it could be due to a faulty Magnetron, burned-out filament, or a malfunctioning high-voltage diode.
Understanding the most common parts that can break in a microwave, such as the magnetron, door switches, turntable, control panel, and high voltage components, can help users identify issues early and seek professional repairs or replacements.
The most likely cause is that the diode, which increases the voltage to the magnetron, has burned out. If this is the case, then the magnetron can't receive enough power to generate microwaves. These can usually be replaced for a low cost.
If the cost of repairing a microwave comes close to or exceeds the price of a new one, it might make more financial sense to replace it. However, if the costs of repairing are relatively low and the microwave isn't too old, it could be worth repairing the microwave.
Testing is to be performed by placing a large mug of water in the microwave oven, whilst putting it on maximum power for a minute. The calibrated microwave leakage tester will then be used to scan door seals and the front glass.
On average, a microwave can last between 9 to 10 years before it may need replacement. However, this can vary depending on the brand, model, usage, and maintenance. While older microwaves can still be safe to use, it's essential to inspect them regularly for any signs of wear and tear.
Repair versus replace
Ilya Uvaydov, owner of Urban Appliances Repair in Daly City, California, says the only microwaves he typically repairs are high-end models made by Viking, Thermador and other luxury brands. The cost to fix these units ranges from $200 to $600, depending on the problem.
Place a glass bowl (preferably a 2 quart glass measuring bowl) filled with 1 quart of water in the center of the Microwave Oven cavity. The water temperature must be between 59 to 75 degrees Fahrenheit (15 to 24 degrees Celsius). Heat the water for exactly 2 minutes and 30 seconds on the High power level.
If the inner case is damaged, rusted, with holes, or not making a perfect seal with door, radiation can leak. This is dangerous to humans. Also, if the damage is severe, the magnetron gets very hot and fails. Or in rare cases, the power supply may catch fire.
Take Your Microwave to an Electronics Store
Some electronics stores will buy your old microwave from you for the parts and recycle whatever can't be used. Some larger electronics stores and chains offer a waste drop-off box in certain locations if the microwave can't be salvaged or you no longer need it.
Misset functions or broken parts are often to blame when your microwave is not heating up. Settings like Control Lock Mode, Demo Mode or power levels set too low may be preventing food from cooking, or more complex causes like a broken magnetron, door switch or high voltage diode could be the source of the problem.
A screaming or screeching sound that's hard to ignore is usually caused by a defective or worn-out magnetron.
If you're not sure if your microwave has been damaged, you can test it by putting a microwave-safe container with water inside and then running it for a minute. If the water isn't hot, the microwave has been damaged. If the microwave still heats, it hasn't been damaged and can still be used safely.