MW850 Microwave - Instructions

Removed control panel, discharged HV capacitor. Removed old diode, tested to confirm failure. Replaced part. Other than the removal of the panel swapping the part was almost as easy as replacing a light bulb.

Ordered a new door frame morning of March 25.
Part arrived the next morning and by that afternoon, the
replacement was complete. Only four screws held the frame.

The microwave is the upper unit of combination microwave & conventional oven. Disconnect power to the unit. Slide unit out of built-in cabinet to expose the top shield of the microwave. Remove 5 screws holding top cover in place. Remove cover, which exposes the belt reel and drive motor. Install the new belt by threading it on the dr ... Read more ive motor pulley, then walk the new belt on the stirrer pulley. Replace the top cover and reinstall the 5 screws. Reinstall the combination unit in the wall cabinet. Reconnect electrical power. Task Complete. The belt just seem to die of old age about every seven year. Without the wave disperser operating, the microwave oven does not give even heating.

First I read through the customer comments, reviews, questions, etc. at Parts Select, which is always a good bet. Then I put "samsung microwave door switch replacement" into youtube and watched some videos. They don't even have to be for Samsung. From what I can tell, many of the appliance companies use the same design and the same jun ... Read more k parts, so watching a GE video is almost the same for example. Watch some videos to familiarize yourself with the steps. There are maybe six to disassemble and install the new part. I replaced all three switches. They are not expensive and to replace 3 is only 5% more work than to replace just one; you have to take the microwave apart in either case. UNPLUG THE MICROWAVE FROM THE WALL. Start taking it apart. I use my phone to take a picture of any thing I remove, unscrew or disconnect, especially wires, BEFORE I disconnect them. Thee pictures serve as a reference when I go to reconnect and reassemble. If I am uncertain then I check the picture. Good luck!

I removed the outer cover and exposed the inner workings. I watched a video on partselect.com to show how to remove and replace the Diode. I followed the instructions and it was very easy to replace.

Unfortunately, the diode was only part of the issue. I ended up replacing the High Voltage capacitor and Magnetron also. Those w ... Read more ere a little more complicated but still easy to do.

Now the Microwave works just like new! Cost me less than $100 for all parts.

The high voltage tired was shorted. I replaced it with a new one, but that did not solve the problem.

You can test the high voltage tired with a voltmeter and a 9 V battery. Search Search for it on YouTube.

You can also test the high voltage capacitor, the high-voltage transformer, and the magnetron with a multi met ... Read more er. Search for the procedures on YouTube.

I tested all these high-voltage components with a low-voltage multi meter, and they all checked out OK (after replacing the diode). However the microwave still did not heat food.

When working on a microwave it is important to unplug it and also discharge the high voltage capacitor. The capacitor has a 10 megaohm resister to automatically discharge itself, but it may have failed – – so discharge it manually.

In the end I ordered a new microwave.

I didn't. Don't know how to get to light bulb to change it for this specific model

I replaced all 3 door switches. Once you remove the top vent then remove the panel. Then remove the two screws holding the door switches in place and pop them out and replace them. It was tricky getting around all the wires but eventually was able to get around them. Took less than 20 mins to do and was less than $40 to fix. Much better t ... Read more han having to replace our over the stove microwave.

Unplugged the unit. With a screwdriver removed two screws on the top plastic vent. This exposed the screw holding the control panel. Removed that screw to access the switches. Removed the visible connected wiring from the switches. Grabbed each switch with pliers to gentle pull them from their holders. Inserted new switches and reconnecte ... Read more d wiring, ensuring the correct orientation of switches in their holders.
Recommend replace all three switches.

Snipped four corners off inspection panel,removed one phillips screw and two elect. Connections. Reverse process.

removed seven screws to take door apart and replace button. Glad that you still had the part for a 25-year-old unit.

Other tools that are usefull long needle nose pliers, long thin blade screw driver and small magnetic flashlight. Place the microwave on a work bench and remove the case it cover 3 sides. Place the microwave on a chair so it can stand with the controls up. You are replacing the lower door microswitch. The switch is located behind the ... Read more control panel in the lower part of the area. The switch is several inches inside this area and your hands will not fit. Take care when moving wires and a couple of sensors. Use the thin blade screwdriver to release a tab holding the switch in place. Do not break this tab. Take the needle nose pliers and remove the switch. Put the wires on the new switch, open the door a short distance so a door lever moves enough to put the microswitch back into the bracket.

Before ordering any parts I remembered seeing a fan above the nylon roof of the microwave. I had seen a belt that drove it on a prior repair 3 years ago.

I then removed 1 screw holding the electrical panel so I could tilt it open. Since power was still plugged in I didn't put my hand in. I used a flashlight and the broken bel ... Read more t.

I could also see the moter that turned the belt and tested it by starting and stopping the microwave and could see the motor pulley spin when it slowed to a stop. I then closed the control panel and screwed it in place.

That confirmed I proceded to go to the internet with the model # for the rane/microwave and looked for parts.

I had an easy job looking the part and saw that the fan as I had called it was named Stirrer because it kept stirring the microwaves over the food.

Overall I looked at 2 venders and chose Part Select because they showed the same catalog page and part numbers, and they had a better price.

I had my part/ belt in 4 working days and installed the new belt in about 15 minutes. This time unplugging the range so there was no power to be concerned with. It was a matter of picking out the old belt and putting the new belt on the motor then walking the belt over the large pulley at the Stirrer since the belt will stretch a bit.

Buttoned it up and later tested with popcorn and it left only a small amount of old maids.

Thanks, Walt

Removed the ice brucket,
Removed the light shield by releasing one screw using a nutdriver.
Replacing the bulb and reinstalled the light shield.

Your web site is one of the best and most helpfull service sites I ever used. Just wish that in the future you will ship parts overseas.

This microwave is the upper unit in combination with an oven. Microwave portion is Model RM288PXS. Cut power at breaker box. Remove metal frame around 2 sides and top, (5 screws). Remove 4 screws on bottom, whicn anchors the unit to the frame.Remove contol panel (2 screws at top) and swing down. Pull out female electrical socket at ... Read more bottom right back in conrol unit space. Now pull out microwave from frame about 6-8 inches. This provides access to pulleys on the motor and wave disperser. Put on belt. Reverse the above procedure to finalize the repair. This is the 3rd time I have had to replace this belt. They last about 6-7 years. Without the wave disperser , the microwave does not provide even heat.