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Steve B[_10_] Steve B[_10_] is offline
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Default microwave/oven combo


"larry moe 'n curly" wrote in message
...


Steve B wrote:

My DIL has a bake oven with a combo microwave. The microwave died, and
the
repair guy said that the microwave couldn't be fixed. I find that hard
to
believe. The unit is not that old. Are there things in a microwave that
go
out that one just absolutely cannot repair?


In a microwave-only oven, yes, because repair is more expensive than a
whole oven, but in a convection-microwave, I think only a broken oven
cavity (has anybody taken a sledge hammer to it recently?) or a bad
high voltage transformer can make repair uneconomical. BTW if this
is a table top model, L-G makes one for GE and also for Sears, the
differences being price and one having a touch panel while the other
having regular buttons.

A microwave oven consists of a fan-cooled magnatron powered by a high
voltage doubler (capacitor, diode), connected to a high voltage
transformer, connected to some control circuitry (simple relay or
inverter) and the 120VAC. There's probably also a high temperature
cutoff for the magnatron. Magnatrons cost as little as $30, the high
voltage capacitor and diode maybe $20-30 for both, and my parents have
a 30-year-old convection/microwave oven that's been fixed 3-4 times by
replacing those components plus the hi-temp cutoff. Also ovens with
touch panels may wear out their buttons or develop cracked solder
joints from flexing too much. If your oven buzzed briefly just before
quitting, there's a good chance the diode shorted.

www.repairFAQ.org has lots of repair information, including safety
information. Microwave ovens can electrocute (kill) you even when
unplugged, because of that big capacitor, whose built-in bleeder
resistor sometimes cracks and doesn't bleed down the 2,000 volts.


reply: here's the deal. I asked my wife, since she has actually looked at
the unit, and I have paid it no attention at all while at my daughter's
house. It's a microwave over a regular oven, all in one face plate. I
would have never bought it, but they are getting a whole new one, and are
giving us this one on hopes we can fixit, as I am known for fixing things in
the family, and everything that goes to the landfill usually goes through my
house first, and I've revived a lot of stuff. I may see it this week, or
after Thanksgiving, and get some more detailed info.

But thanks for the boost that it may be repairable.

Steve