Fuseholder melted overdrawing amps and not heating amana hcd18sd

Luzetta
This is a common problem with microwave ovens and is easy to diagnose. Whenever I replace the fuse, I always perform this test. I don't want the unit coming back in a couple of days with the same problem.
Install a known good fuse. It should be a 20 Amp, Slo-Blo, with a ceramic body. Leave the cover off. Place a container with at least 2 cups of water inside the unit. Cook on high for at least 5 minutes. As soon as it finishes, UNPLUG the unit and feel the fuse. If it is extremely hot, the fuse is going to fail in a short period of time. The fusible material inside the fuse is melting from this excessive heat. It only takes a small amount of resistance at the fuse holder contacts to create this amount of heat. Replace the fuse holder rated at least 20 Amps. The higher the better.

open the cabinet

this must be an oldie cus im not in the knowlege of any microwaves that are sealed with grout , most all today are heat sealed using an ultrasonic weld that i know of
but i caution you using non food grade materials inside any oven, heat generated by cooking may leak out chemicals in sealers and "grout" that are not designed for food and poision the food inside id contact Amana directly and inquire about them selling you a tube of this sealer ?

For safety sake the cord should be replaced, the microwave ovens draw several amps when running.

HI. Your symptoms are a strong indication Magnetron failure. This is the principal heating device, that is used to produce microwaves that , essentially, excite the water molecules in the food, thus, producing the heating effect. When this device fails, generally, the unit will run, but not heat. This device is very fragile, and can injure you if you are not qualified to handle this type of component. There is a High Voltage Capacitor, that is used to help provide the necessary current for optimal Magnetron operation. This capacitor must be discharged correctly. If not, you could risk serious injury, during the repair, if it is accidental touched.

The Magnetron is linked to a cut-off fuse. If the magnetron becomes unstable, this fuse will shut the device down. It is standard procedure to have this fuse test for continuity. If the fuse has blown, this will be the culprit. Replace the fuse. Now, if the fuse continues to show continuity, this will confirm that the Magnetron has failed. I would advise to inspect the Capacitor, and HV diode for visible burn marks, or swollen top(Cap).

Access can be ac hived to these parts by removing the outside cabinet screws. Once the screws are removed, the cover can be removed, as well. Once the cover is removed, the internal components will be exposed for testing, and visual inspections.

WARNING: IF YOU ARE NOT A QUALIFIED SERVICE TECH, THIS WILL NOT BE A NOVICE DO IT YOURSELF JOB. MICROWAVES ARE VERY DANGEROUS, AND CAN CAUSE SERIOUS INJURY. I RECOMMEND TO CALL FOR SERVICE, IF YOU ARE UNCOMFORTABLE WITH HANDLING THE CAPACITOR, OR MAGNETRON.

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Your drain tube may be stopped up with ice at the upper end because it drains too slow because it's stopped up at the lower end in the evaporator pan under the unit at the floor. It can get dust and mold in it. Once you get the ice out at the top a little pressure with a turkey baster will usually clear it out. Flushing it out with hot water and clorox may help.
Make sure it drains quick enough to prevent refreezing. . The drain should be located below the evaporator coils on the lower back of the freezer.

This heat could have come from excess current draw due to a failing part, such as the magnetron, or an improper voltage level at the outlet. It should measure 105-125VAC.

A loose connection can also result in heat and melting.

I would recommend replacing the section of wire that's melted. You need to make a good solid connection with proper wire nuts and solid crimped connectors.

If you think the TCO may have been stressed, it should be replaced, too.

I would also check the fuse holder by seeing if you can twirl the fuse with your bare fingers while it's in the holder. If so, then it is too loose and the holder must be replaced.

You cannot just squeeze it tighter with pliers, because metal fatigue will make it go loose again, possibly resulting in a melted fuse.

Lastly, I would replace the primary interlock (top door switch). See http://www.microwavedisplay.com/doorsw.txt.

Then make sure that no one opens the door while the oven is cooking unless it is specifically called for in the cooking cycle. Opening the door while it is cooking leads to premature switch failure and heat / melting of the switches connectors and wiring.

You can find the full service manual online here.

Yours may have the revised circuit. You can see the "mini-manual" for that version here.

There should also be a "mini-manual" hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, & testing.



At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

You can find links to helpful exploded view diagrams and part ordering help here.

I'd recommend that your bookmark this link to your favorites.

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

This sounds like either a thermistor or a damper switch/motor problem.
Amana's technical support line is 866-426-2621. This is the commercial side but they should be able to get you in touch with the domestic side.

Most of does have fuse on them.If you will look somewhere around the back of oven where the power cord come in.Most of them have a ceramic fuse.20 amp.

The two possible causes are a faulty door switch and a bad magnatron. You can pull the top cover off of the unit and check all of the door switches (there are 2-6 of them all on a common rail, me normally closed)). If the door switches all check out, replace the magnatron, diodes, and capacitor.