Microwave failing

[harryhef]

I have an 8-year-old Kenmore above-range microwave that is failing.
Beginning a few month ago it started buzzing (sounds like a relay or
chattering) and then it starts -- or not. The controller seems to work
fine, and if it starts squirting microwaves it works fine, but more
and more now it won't start and won't heat anything. What does it
sound like is failing? Any ideas about repair? I do have experience
with HV and have a lot of respect for charged caps! Maybe it would be
better to just discard it and purchase a new one, but I hate to do
that if this one is reasonably economically repairable. Sears wants
$130 plus parts to repair. Thanks for any advice, -Harry

 

[Samuel M. Goldwasser]

harryhef <harryhef@gmail.com> writes:

I have an 8-year-old Kenmore above-range microwave that is failing.
Beginning a few month ago it started buzzing (sounds like a relay or
chattering) and then it starts -- or not. The controller seems to work
fine, and if it starts squirting microwaves it works fine, but more
and more now it won't start and won't heat anything. What does it
sound like is failing? Any ideas about repair? I do have experience
with HV and have a lot of respect for charged caps! Maybe it would be
better to just discard it and purchase a new one, but I hate to do
that if this one is reasonably economically repairable. Sears wants
$130 plus parts to repair. Thanks for any advice, -Harry

It may in fact be a relay chattering. Possibly something as simple
as a bad filter capacitor in the low voltage controller power supply.

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[William R. Walsh]

Hi!

I have an 8-year-old Kenmore above-range microwave that is failing.
Beginning a few month ago it started buzzing (sounds like a relay or
chattering) and then it starts -- or not.

The relay might very well be failing or bad. It is switching a lot of
current in that application and might have burned contacts.

See if Sears will sell you the part, and if so, what they'd ask. It might
actually be reasonably priced and easier than trying to get one through a
components dealer. If you can solder, you can put it into place no problem.

REMEMBER: A microwave utilizes high voltage at high current to do what it
does. This combination can prove to be much more dangerous (lethal in fact)
than most other high voltage devices. Do not touch any wiring while the oven
is operating, and be mindful of the high voltage components at all times. Be
sure to discharge the capacitor before working on the oven and every time
after operating it.

William