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Recommended repair or magnetron replacement of broken microwave (Jenn-Air M170B)
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Danny D.
Dec 17, 2012, 12:04:25 PM12/17/12
to
This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
I called Jenn-Air customer support who said there's no troubleshooting for
when it doesn't heat. They said the magnetron may need to be replaced:
Jenn-Air 800-536-6247 Customer Care
A replacement microwave oven has to fit over the electric oven:
http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
Interestingly, (since it was above the oven) the back sticker says:
"May be built into a cabinet structure, but not for use adjacent
to (with 2 feet of) any gas or electric range, cooktop or oven."
http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
But, that sticker also says:
This microwave is approved for mounting directly over Jenn-Air
wall ovens as follows:
W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
Having never worked on a microwave, I ask what the conventional wisdom is.
Q: Is it generally feasible to replace just the magnetron?
Q: Will similarly sized microwave ovens fit (22" widex13"tallx15" deep)?
Q: Is it generally best to stick within the same brand? (e.g., JMC1116AB)?
http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
I called Jenn-Air customer support who said there's no troubleshooting for
when it doesn't heat. They said the magnetron may need to be replaced:
Jenn-Air 800-536-6247 Customer Care
A replacement microwave oven has to fit over the electric oven:
http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
Interestingly, (since it was above the oven) the back sticker says:
"May be built into a cabinet structure, but not for use adjacent
to (with 2 feet of) any gas or electric range, cooktop or oven."
http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
But, that sticker also says:
This microwave is approved for mounting directly over Jenn-Air
wall ovens as follows:
W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
Having never worked on a microwave, I ask what the conventional wisdom is.
Q: Is it generally feasible to replace just the magnetron?
Q: Will similarly sized microwave ovens fit (22" widex13"tallx15" deep)?
Q: Is it generally best to stick within the same brand? (e.g., JMC1116AB)?
gonjah
Dec 17, 2012, 12:19:38 PM12/17/12
to
just replace it.
FWIW: Panasonic makes a really good microwave. "Invertor" 1300W. But I
think you need one that's insulated to protect it from the heat of the oven.
Smitty Two
Dec 17, 2012, 12:19:35 PM12/17/12
to
In article <kanjao$42t$1...@speranza.aioe.org>,
<http://sell.lulusoso.com/selling-leads/648523/T1-11-BH2-thermal-cut-off.
html>
You should find a schematic inside the unit after you take off the
cover. With some basic electronic troubleshooting skills you can
identify which of the 2-3 thermal cutoffs has gone bad. They're cheap
and generic, but come in different temp ranges.
(Now, have fun turning this thread into a 500 post thread, while all the
helpful people teach you how to read a schematic and use your
multimeter, and arm you with enough info to write the internet's most
definitive treatise on microwave oven repair.)
"Danny D." <da...@dyahoo.com> wrote:
> Having never worked on a microwave, I ask what the conventional wisdom is.
Probably just needs a new thermal cutoff. This random page has a picture.
> Having never worked on a microwave, I ask what the conventional wisdom is.
<http://sell.lulusoso.com/selling-leads/648523/T1-11-BH2-thermal-cut-off.
html>
You should find a schematic inside the unit after you take off the
cover. With some basic electronic troubleshooting skills you can
identify which of the 2-3 thermal cutoffs has gone bad. They're cheap
and generic, but come in different temp ranges.
(Now, have fun turning this thread into a 500 post thread, while all the
helpful people teach you how to read a schematic and use your
multimeter, and arm you with enough info to write the internet's most
definitive treatise on microwave oven repair.)
tra...@optonline.net
Dec 17, 2012, 12:23:04 PM12/17/12
to
On Dec 17, 12:04 pm, "Danny D." <da...@dyahoo.com> wrote:
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no troubleshooting for
> when it doesn't heat. They said the magnetron may need to be replaced:
> Jenn-Air 800-536-6247 Customer Care
>
> A replacement microwave oven has to fit over the electric oven:
> http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
>
> Interestingly, (since it was above the oven) the back sticker says:
> "May be built into a cabinet structure, but not for use adjacent
> to (with 2 feet of) any gas or electric range, cooktop or oven."
> http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
>
> But, that sticker also says:
> This microwave is approved for mounting directly over Jenn-Air
> wall ovens as follows:
> W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
>
> Having never worked on a microwave, I ask what the conventional wisdom is.
> Q: Is it generally feasible to replace just the magnetron?
Technically, probably yes. But, there are some obvious
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no troubleshooting for
> when it doesn't heat. They said the magnetron may need to be replaced:
> Jenn-Air 800-536-6247 Customer Care
>
> A replacement microwave oven has to fit over the electric oven:
> http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
>
> Interestingly, (since it was above the oven) the back sticker says:
> "May be built into a cabinet structure, but not for use adjacent
> to (with 2 feet of) any gas or electric range, cooktop or oven."
> http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
>
> But, that sticker also says:
> This microwave is approved for mounting directly over Jenn-Air
> wall ovens as follows:
> W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
>
> Having never worked on a microwave, I ask what the conventional wisdom is.
> Q: Is it generally feasible to replace just the magnetron?
problems. One is, there are a lot of things that could cause
it to stop heating, only one of which is the magnetron.
Figuring out which it is, unless you have the suitable
skills, schematics, etc will require a tech, service fee, etc.
The second is that if it is the magnetron, what does a new
one cost? Could very likely be buckoo bucks. Generally,
given the cost of a new regular microwave, it's not worth
screwing around with. But since this is part of a built-in
JennAire, I feel your pain.
> Q: Will similarly sized microwave ovens fit (22" widex13"tallx15" deep)?
and match other companies products into that JennAir
frame. For some odd reason, JennAir doesn't want you
to be able to do that.....
> Q: Is it generally best to stick within the same brand? (e.g., JMC1116AB)?
I did a mini makeover of the kitchen and got rid of it.
It was still working, but was outdated. So, I found a
Kitchenaid double oven on Ebay. It was a floor model,
but in perfect condition except for some sale stickers.
That unit retailed for $3000. I got it for $1200. It was
also a 30", which is a good thing, where the existing was 27".
I had to carefully scope out the cabinet situation where
it was going. And I had to cut apart the cabinet to make it
fit. Including taking the cabinet from above to a cabinet
shop and having them cut several inches off the bottom.
But it came out great. Looks 1000% better.
I also like the idea of double ovens a lot more than the
built-in microwaves. The look much nicer, are a selling
point for kitchens today. And from what I have seen,
the microwaves from the major kitchen appliance/oven
manufacturers cost $1000 and suck compared to the
$100 countertop model. They tend to be no larger,
more confusing controls, don't heat as well. If the $100
one goes, you just buy another.
Just some things to consider. Maybe you should buy
a countertop one and look for a great deal on a new
double oven.....
gonjah
Dec 17, 2012, 1:07:35 PM12/17/12
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On 12/17/2012 11:04 AM, Danny D. wrote:
for your opening. That way you don't have to worry about the exact size.
I know Sears and Lowes sells them. HD probably does too.
mike
Dec 17, 2012, 1:47:00 PM12/17/12
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On 12/17/2012 9:19 AM, Smitty Two wrote:
> In article<kanjao$42t$1...@speranza.aioe.org>,
> "Danny D."<da...@dyahoo.com> wrote:
>
>> Having never worked on a microwave, I ask what the conventional wisdom is.
>
> Probably just needs a new thermal cutoff. This random page has a picture.
>
> <http://sell.lulusoso.com/selling-leads/648523/T1-11-BH2-thermal-cut-off.
> html>
>
> You should find a schematic inside the unit after you take off the
> cover. With some basic electronic troubleshooting skills you can
> identify which of the 2-3 thermal cutoffs has gone bad. They're cheap
> and generic, but come in different temp ranges.
Check fuses and electrical connections. I had one where corrosion
> In article<kanjao$42t$1...@speranza.aioe.org>,
> "Danny D."<da...@dyahoo.com> wrote:
>
>> Having never worked on a microwave, I ask what the conventional wisdom is.
>
> Probably just needs a new thermal cutoff. This random page has a picture.
>
> <http://sell.lulusoso.com/selling-leads/648523/T1-11-BH2-thermal-cut-off.
> html>
>
> You should find a schematic inside the unit after you take off the
> cover. With some basic electronic troubleshooting skills you can
> identify which of the 2-3 thermal cutoffs has gone bad. They're cheap
> and generic, but come in different temp ranges.
eventually overheated the connection on the door switch and disabled
it.
I've fixed a few microwaves, and almost all had bad diodes.
Certainly possible, but I've never seen a bad magnetron.
Be aware that the big cap can hold enough charge to kill you
after days and days being off.
Even if you don't get electrocuted, you can be seriously injured
when you fly across the room and bang your head on the counter.
And you'll be scraping pieces of skin off the sharp edges of the case.
I don't know of a good DIY way to discharge the cap. I once made the
mistake of shorting it with a wire. Scared the crap outa me when
the wire exploded.
John Keiser
Dec 17, 2012, 2:28:41 PM12/17/12
to
I agree with Mike: use common sense and due caution. I've fixed many
microwaves and never seen a dead magnetron. Diode [cheap] has been the most
common failure. More irksome is a dead control panel. [I have a 30 year old
Toshiba going strong with a sturdy dial timer.] I'd stay away from the
Panasonic "inverter" models as there is no reason [unless you care about
weight savings from not having a heavy transformer] to over-complicate these
simple circuits with an inverter.
"gonjah" <jth...@toast.net> wrote in message
news:kank76$od8$1...@dont-email.me...
microwaves and never seen a dead magnetron. Diode [cheap] has been the most
common failure. More irksome is a dead control panel. [I have a 30 year old
Toshiba going strong with a sturdy dial timer.] I'd stay away from the
Panasonic "inverter" models as there is no reason [unless you care about
weight savings from not having a heavy transformer] to over-complicate these
simple circuits with an inverter.
"gonjah" <jth...@toast.net> wrote in message
news:kank76$od8$1...@dont-email.me...
gonjah
Dec 17, 2012, 2:50:41 PM12/17/12
to
On 12/17/2012 1:28 PM, John Keiser wrote:
> I agree with Mike: use common sense and due caution. I've fixed many
> microwaves and never seen a dead magnetron. Diode [cheap] has been the most
> common failure. More irksome is a dead control panel. [I have a 30 year old
> Toshiba going strong with a sturdy dial timer.] I'd stay away from the
> Panasonic "inverter" models as there is no reason [unless you care about
> weight savings from not having a heavy transformer] to over-complicate these
> simple circuits with an inverter.
Could be. I'm not sure what the inverter does. I've been using mine
> I agree with Mike: use common sense and due caution. I've fixed many
> microwaves and never seen a dead magnetron. Diode [cheap] has been the most
> common failure. More irksome is a dead control panel. [I have a 30 year old
> Toshiba going strong with a sturdy dial timer.] I'd stay away from the
> Panasonic "inverter" models as there is no reason [unless you care about
> weight savings from not having a heavy transformer] to over-complicate these
> simple circuits with an inverter.
daily for over 7 years now. It does have quite a few options.
mike
Dec 17, 2012, 3:20:18 PM12/17/12
to
On 12/17/2012 11:28 AM, John Keiser wrote:
> I agree with Mike: use common sense and due caution. I've fixed many
> microwaves and never seen a dead magnetron. Diode [cheap] has been the most
> common failure. More irksome is a dead control panel. [I have a 30 year old
> Toshiba going strong with a sturdy dial timer.] I'd stay away from the
> Panasonic "inverter" models as there is no reason [unless you care about
> weight savings from not having a heavy transformer] to over-complicate these
> simple circuits with an inverter.
>
Inverter should let you have continuous power control.
> I agree with Mike: use common sense and due caution. I've fixed many
> microwaves and never seen a dead magnetron. Diode [cheap] has been the most
> common failure. More irksome is a dead control panel. [I have a 30 year old
> Toshiba going strong with a sturdy dial timer.] I'd stay away from the
> Panasonic "inverter" models as there is no reason [unless you care about
> weight savings from not having a heavy transformer] to over-complicate these
> simple circuits with an inverter.
>
I cheaped out when I replaced mine and didn't get an inverter. I regret
that decision.
It has 3X the power of the old one. And the 15-second on-time is
way too long for power regulation on small loads.
Danny D.
Dec 17, 2012, 3:58:50 PM12/17/12
to
On Mon, 17 Dec 2012 09:19:35 -0800, Smitty Two wrote:
> Probably just needs a new thermal cutoff.
I found only one so far - and it checked out at 0.5 ohms:
> Probably just needs a new thermal cutoff.
http://www3.picturepush.com/photo/a/11712046/img/11712046.jpg
> You should find a schematic inside the unit
http://www3.picturepush.com/photo/a/11712051/img/11712051.jpg
> arm you with enough info to write the internet's most
> definitive treatise on microwave oven repair.
trying to do is make a good decision as to how to proceed.
Danny D.
Dec 17, 2012, 4:00:35 PM12/17/12
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On Mon, 17 Dec 2012 10:47:00 -0800, mike wrote:
> I've fixed a few microwaves, and almost all had bad diodes.
> I've fixed a few microwaves, and almost all had bad diodes.
> Be aware that the big cap can hold enough charge to kill you
I don't see any diodes yet; but I do see the big cap you speak of:
http://www5.picturepush.com/photo/a/11712053/img/11712053.jpg
Danny D.
Dec 17, 2012, 4:03:12 PM12/17/12
to
On Mon, 17 Dec 2012 09:28:41 -1000, John Keiser wrote:
> More irksome is a dead control panel.
I'm wiggling everything on that control panel as we speak:
> More irksome is a dead control panel.
http://www1.picturepush.com/photo/a/11712239/img/11712239.jpg
Danny D.
Dec 17, 2012, 4:04:24 PM12/17/12
to
On Mon, 17 Dec 2012 09:23:04 -0800, tra...@optonline.net wrote:
> Maybe you should buy a countertop one and look for a great
> deal on a new double oven.....
I had never thought of that; thanks for the good idea.
> Maybe you should buy a countertop one and look for a great
> deal on a new double oven.....
Looks like the bottom oven is a 27 inch variety.
Danny D.
Dec 17, 2012, 4:05:56 PM12/17/12
to
On Mon, 17 Dec 2012 12:20:18 -0800, mike wrote:
> Inverter should let you have continuous power control.
I'm confused why an inverter is needed for an AC appliance.
> Inverter should let you have continuous power control.
I do see three voltage transformers though.
http://www4.picturepush.com/photo/a/11712047/img/11712047.jpg
Danny D.
Dec 17, 2012, 4:12:26 PM12/17/12
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On Mon, 17 Dec 2012 12:07:35 -0600, gonjah wrote:
> If you do replace it, I'm pretty sure you can find a replacement trim
> for your opening. That way you don't have to worry about the exact size.
Good to know!
> If you do replace it, I'm pretty sure you can find a replacement trim
> for your opening. That way you don't have to worry about the exact size.
I'll bring the trim with me when I buy the replacement.
BTW, here's a full-size schematic where I'm looking for the
thermal switch and fuses.
http://www3.picturepush.com/photo/a/11712316/img/11712316.jpg
EXT
Dec 17, 2012, 4:37:42 PM12/17/12
to
"Danny D." <da...@dyahoo.com> wrote in message
news:kanjao$42t$1...@speranza.aioe.org...
fuse, I have had a number go for no reason. Replace it and you are good
again until it blows again in a few years. Second check the micro switches
on the door latches, they interlock for safety, if one fails the oven will
not work. There sometimes are three of them, some normally open and some
normally closed, check them with a meter.
Beyond that I have had one that burnt out a thin wire that carried about 13
amps, and then needed another part, it was cheaper to replace it than repair
it.
Stormin Mormon
Dec 17, 2012, 6:04:40 PM12/17/12
to
I've found microwaves tend to have a high voltage diode, and a high voltage
capacitor. Both are known to go bad. I've repaired several microwave ovens,
and it's been these two parts.
Christopher A. Young
Learn more about Jesus
www.lds.org
.
capacitor. Both are known to go bad. I've repaired several microwave ovens,
and it's been these two parts.
Christopher A. Young
Learn more about Jesus
www.lds.org
.
Stormin Mormon
Dec 17, 2012, 6:07:35 PM12/17/12
to
The ones I've worked on, the diode is connected to the cap.
Your diode might be going from cap to the case of the unit.
Christopher A. Young
Learn more about diodes
news:kao15i$ao0$2...@speranza.aioe.org...
Your diode might be going from cap to the case of the unit.
Christopher A. Young
Learn more about diodes
news:kao15i$ao0$2...@speranza.aioe.org...
Stormin Mormon
Dec 17, 2012, 6:10:32 PM12/17/12
to
Part labelled "H.V. Diode". Next to the magnetron, about 7 o'clock from the
magnatron. Goes to case ground, like my last post suggested.
Christopher A. Young
Learn more about Jesus
news:kao1rp$ao0$6...@speranza.aioe.org...
magnatron. Goes to case ground, like my last post suggested.
Christopher A. Young
Learn more about Jesus
news:kao1rp$ao0$6...@speranza.aioe.org...
John Keiser
Dec 17, 2012, 6:52:22 PM12/17/12
to
In this case I believe the "inverter" is basically a switch mode power
supply to do away with the heavy transformer traditionaly used in
microwaves. Think of the PSU in your computer. As another poster mentions,
this does allow for finer power control but I never need that degree of
control in our cooking. And I've read complaints of invert failures. For
me, simple is better.
news:kao1fk$ao0$5...@speranza.aioe.org...
supply to do away with the heavy transformer traditionaly used in
microwaves. Think of the PSU in your computer. As another poster mentions,
this does allow for finer power control but I never need that degree of
control in our cooking. And I've read complaints of invert failures. For
me, simple is better.
news:kao1fk$ao0$5...@speranza.aioe.org...
gregz
Dec 17, 2012, 7:35:07 PM12/17/12
to
More efficiency less weight, no big expensive power transformer.
A magnetron has to be run full power. You just turn it on an off as needed.
In troubleshooting my brothers microwave, I forgot the exact steps we took.
Ended up wasting money before finding out transformer was bad.
Greg
HeyBub
Dec 17, 2012, 8:22:18 PM12/17/12
to
Danny D. wrote:
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no
> troubleshooting for when it doesn't heat. They said the magnetron may
> need to be replaced: Jenn-Air 800-536-6247 Customer Care
>
"When it doesn't heat..." Do you mean the microwave does everything else
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no
> troubleshooting for when it doesn't heat. They said the magnetron may
> need to be replaced: Jenn-Air 800-536-6247 Customer Care
>
EXCEPT heat the contents? That is does if LOOK like it's working, turntable
goes round, light comes on, timer works? If so, replacing the magnetron is a
good first guess.
I say this because the other stuff is governed by a printed circuit board
that has three to ten dodgy electrolytic capacitors on it. Replacing these
capacitors is pretty easy and pretty cheap.
Danny D.
Dec 17, 2012, 10:06:52 PM12/17/12
to
On Mon, 17 Dec 2012 18:07:35 -0500, Stormin Mormon wrote:
> The ones I've worked on, the diode is connected to the cap.
> Your diode might be going from cap to the case of the unit
Ah, there was something there.
> The ones I've worked on, the diode is connected to the cap.
> Your diode might be going from cap to the case of the unit
http://www5.picturepush.com/photo/a/11714203/img/11714203.jpg
But it looks more like a rectangular ceramic resistor than a tubular
diode.
I haven't measured it due to the warnings about the charge on the
capacitor.
Today I looked at Lowes but they didn't have any black 22 inch by 13 inch
microwaves. The size seems to be the biggest hurdle.
Danny D.
Dec 17, 2012, 10:14:48 PM12/17/12
to
On Mon, 17 Dec 2012 19:22:18 -0600, HeyBub wrote:
> "When it doesn't heat..." Do you mean the microwave does everything else
> EXCEPT heat the contents?
Yes. EVERYTHING, fan, lights, table, controls, etc. ... everything else
> "When it doesn't heat..." Do you mean the microwave does everything else
> EXCEPT heat the contents?
is working. The only thing that is not working is nothing gets heated.
hr(bob) hofmann@att.net
Dec 17, 2012, 10:45:33 PM12/17/12
to
in power output so thing take longer and longer to get hot. If you
can locate the two wires going to the magnetron filament, you should
see someting less than 100 ohms for the filament. But, you have to
disconnect one wire from the filament to the power transformer before
you check the filament or you will just see the resistance of the
transformer and not the filament of the magnetron.
croy
Dec 17, 2012, 10:57:20 PM12/17/12
to
fuse & fuse block--badly corroded. Replaced both 5 years
ago, and they're still going strong.
--
croy
The Daring Dufas
Dec 17, 2012, 11:08:35 PM12/17/12
to
all shapes and sizes. ^_^
TDD
Danny D.
Dec 17, 2012, 11:34:17 PM12/17/12
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On Mon, 17 Dec 2012 22:08:35 -0600, The Daring Dufas wrote:
> That's the diode I saw in the pictures and the diagram.
> Diodes come in all shapes and sizes. ^_^
Ah. Thanks. I'll figure out how to discharge the capacitor first.
> That's the diode I saw in the pictures and the diagram.
> Diodes come in all shapes and sizes. ^_^
It has been sitting all day, so maybe by tomorrow it will have discharged.
My Fluke DMM has a diode test mode, so I can at least run that baseline.
Danny D.
Dec 18, 2012, 12:02:16 AM12/18/12
to
On Mon, 17 Dec 2012 19:45:33 -0800, hr(bob) hof...@att.net wrote:
> If you can locate the two wires going to the magnetron filament,
> you should see someting less than 100 ohms for the filament.
I was wondering WHERE the magnetron lay.
> If you can locate the two wires going to the magnetron filament,
> you should see someting less than 100 ohms for the filament.
If these are the magnetron leads, they read 0.4 ohms with the Fluke in
ohms mode:
http://www2.picturepush.com/photo/a/11714385/img/11714385.jpg
And, the diode reads OL in both directions, both forward biased and
reverse biased with the Fluke 75 in the diode mode:
http://www3.picturepush.com/photo/a/11714386/img/11714386.jpg
The Daring Dufas
Dec 18, 2012, 12:10:57 AM12/18/12
to
check for residual voltage with your DVM. There is always The Jesus
Method for discharging caps. ^_^
TDD
Ralph Mowery
Dec 18, 2012, 12:35:25 AM12/18/12
to
news:kaotco$468$2...@speranza.aioe.org...
If you are only on the filiment of the megatron and not in the circuit it is
probably ok. If the megatron is still connected, you may be meauring the
filiment windings of the transformer.
Some high voltage diodes are made of several lower voltage units in series
in the same case. The diode function of the Fluke may not have enough
voltage to check this out and will show open. Here is one way to check to
see if it is actually open.
http://www.flickr.com/photos/zenzoidman/4724416181/
They use a 9 volt battery and the voltage scale of the meter, One way will
show open and the other will show a few volts less than 9 if the diode is
good.
probably ok. If the megatron is still connected, you may be meauring the
filiment windings of the transformer.
Some high voltage diodes are made of several lower voltage units in series
in the same case. The diode function of the Fluke may not have enough
voltage to check this out and will show open. Here is one way to check to
see if it is actually open.
http://www.flickr.com/photos/zenzoidman/4724416181/
They use a 9 volt battery and the voltage scale of the meter, One way will
show open and the other will show a few volts less than 9 if the diode is
good.
Smitty Two
Dec 18, 2012, 12:51:29 AM12/18/12
to
In article <kao1rp$ao0$6...@speranza.aioe.org>,
That looks more like a "block diagram" than a schematic. If you didn't
find a folded up paper schematic tucked inside somewhere, then go online
and find one. I've read other responses, but I'm sticking with a faulty
thermal cutoff as most likely culprit.
find a folded up paper schematic tucked inside somewhere, then go online
and find one. I've read other responses, but I'm sticking with a faulty
thermal cutoff as most likely culprit.
The Daring Dufas
Dec 18, 2012, 1:02:27 AM12/18/12
to
TDD
Danny D.
Dec 18, 2012, 1:35:29 AM12/18/12
to
On Tue, 18 Dec 2012 00:35:25 -0500, Ralph Mowery wrote:
> Here is one way to check to see if it is actually open.
> http://www.flickr.com/photos/zenzoidman/4724416181/
That's a nice procedure which I will try in the morning.
> Here is one way to check to see if it is actually open.
> http://www.flickr.com/photos/zenzoidman/4724416181/
Thanks for pointing it out - as I would have thought the
basic diode function of the Fluke 75 would have sufficed.
At the moment, it shows the diode as bad - but - as you
noted - that may be an anomaly due to the voltage of the Fluke
in diode mode.
Stormin Mormon
Dec 18, 2012, 4:46:02 AM12/18/12
to
From your wiring diagram that you posted earlier, the square black thing is
more likely a high voltage diode. If that goes out, the microwave hums, but
doesn't heat. If the diode goes, I'd expect the cap to lose its charge. You
might have to slice off the heat shrink to reveal the diode markings on it.
Dash, triangle, bar, dash. Somewhat like --|>|-- more or less.
Christopher A. Young
Learn more about Jesus
news:kaomkc$npq$1...@speranza.aioe.org...
more likely a high voltage diode. If that goes out, the microwave hums, but
doesn't heat. If the diode goes, I'd expect the cap to lose its charge. You
might have to slice off the heat shrink to reveal the diode markings on it.
Dash, triangle, bar, dash. Somewhat like --|>|-- more or less.
Christopher A. Young
Learn more about Jesus
news:kaomkc$npq$1...@speranza.aioe.org...
Stormin Mormon
Dec 18, 2012, 4:48:02 AM12/18/12
to
And, all have personal self worth, and self esteem. Until they
go bad. And then they go to a local school and spray every
one with electrons. Using a high power transformer and......
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"The Daring Dufas" <the-dari...@stinky-finger.net>
wrote in message news:kaoq7c$ujs$2...@dont-email.me...
>
> Ah, there was something there.
> http://www5.picturepush.com/photo/a/11714203/img/11714203.jpg
>
go bad. And then they go to a local school and spray every
one with electrons. Using a high power transformer and......
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"The Daring Dufas" <the-dari...@stinky-finger.net>
wrote in message news:kaoq7c$ujs$2...@dont-email.me...
>
> Ah, there was something there.
> http://www5.picturepush.com/photo/a/11714203/img/11714203.jpg
>
Stormin Mormon
Dec 18, 2012, 4:49:48 AM12/18/12
to
Should be infinite ohms one way, and then reverse the leads, and get some
where between 2k (about that) ohms the other way. My SWAG at the moment is
the diode went. If the diode shorted, the cap may be discharged now.
Christopher A. Young
Learn more about Jesus
news:kaoro9$468$1...@speranza.aioe.org...
where between 2k (about that) ohms the other way. My SWAG at the moment is
the diode went. If the diode shorted, the cap may be discharged now.
Christopher A. Young
Learn more about Jesus
news:kaoro9$468$1...@speranza.aioe.org...
Stormin Mormon
Dec 18, 2012, 4:51:31 AM12/18/12
to
<pants and wags tail> Cookie! Cookie!
http://morethanaminute.com/wp-content/uploads/2011/07/Cookie_Monster.jpg
Christopher A. Young
http://morethanaminute.com/wp-content/uploads/2011/07/Cookie_Monster.jpg
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"The Daring Dufas" <the-dari...@stinky-finger.net> wrote in message
news:kaotsb$fnh$1...@dont-email.me...
www.lds.org
.
"The Daring Dufas" <the-dari...@stinky-finger.net> wrote in message
>
> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>
> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>
tra...@optonline.net
Dec 18, 2012, 9:38:32 AM12/18/12
to
On Dec 18, 12:51 am, Smitty Two <notpublici...@cox.net> wrote:
> In article <kao1rp$ao...@speranza.aioe.org>,
to me. It shows the various components and the circuit
connections between them.
> In article <kao1rp$ao...@speranza.aioe.org>,
> "Danny D." <da...@dyahoo.com> wrote:
>
> > On Mon, 17 Dec 2012 12:07:35 -0600, gonjah wrote:
>
> > > If you do replace it, I'm pretty sure you can find a replacement trim
> > > for your opening. That way you don't have to worry about the exact size.
>
> > Good to know!
> > I'll bring the trim with me when I buy the replacement.
>
> > BTW, here's a full-size schematic where I'm looking for the
> > thermal switch and fuses.
> > http://www3.picturepush.com/photo/a/11712316/img/11712316.jpg
>
> That looks more like a "block diagram" than a schematic.
Why do you say that? It sure looks like a schematic
>
> > On Mon, 17 Dec 2012 12:07:35 -0600, gonjah wrote:
>
> > > If you do replace it, I'm pretty sure you can find a replacement trim
> > > for your opening. That way you don't have to worry about the exact size.
>
> > Good to know!
> > I'll bring the trim with me when I buy the replacement.
>
> > BTW, here's a full-size schematic where I'm looking for the
> > thermal switch and fuses.
> > http://www3.picturepush.com/photo/a/11712316/img/11712316.jpg
>
> That looks more like a "block diagram" than a schematic.
to me. It shows the various components and the circuit
connections between them.
Smitty Two
Dec 18, 2012, 11:16:25 AM12/18/12
to
In article
<4881eaf6-b9f3-4015...@r14g2000vbe.googlegroups.com>,
<4881eaf6-b9f3-4015...@r14g2000vbe.googlegroups.com>,
"tra...@optonline.net" <tra...@optonline.net> wrote:
> On Dec 18, 12:51 am, Smitty Two <notpublici...@cox.net> wrote:
> > In article <kao1rp$ao...@speranza.aioe.org>,
> > "Danny D." <da...@dyahoo.com> wrote:
> >
> > > On Mon, 17 Dec 2012 12:07:35 -0600, gonjah wrote:
> >
> > > > If you do replace it, I'm pretty sure you can find a replacement trim
> > > > for your opening. That way you don't have to worry about the exact size.
> >
> > > Good to know!
> > > I'll bring the trim with me when I buy the replacement.
> >
> > > BTW, here's a full-size schematic where I'm looking for the
> > > thermal switch and fuses.
> > > http://www3.picturepush.com/photo/a/11712316/img/11712316.jpg
> >
> > That looks more like a "block diagram" than a schematic.
>
> Why do you say that? It sure looks like a schematic
> to me. It shows the various components and the circuit
> connections between them.
>
Seems a little light on detail.
> On Dec 18, 12:51 am, Smitty Two <notpublici...@cox.net> wrote:
> > In article <kao1rp$ao...@speranza.aioe.org>,
> > "Danny D." <da...@dyahoo.com> wrote:
> >
> > > On Mon, 17 Dec 2012 12:07:35 -0600, gonjah wrote:
> >
> > > > If you do replace it, I'm pretty sure you can find a replacement trim
> > > > for your opening. That way you don't have to worry about the exact size.
> >
> > > Good to know!
> > > I'll bring the trim with me when I buy the replacement.
> >
> > > BTW, here's a full-size schematic where I'm looking for the
> > > thermal switch and fuses.
> > > http://www3.picturepush.com/photo/a/11712316/img/11712316.jpg
> >
> > That looks more like a "block diagram" than a schematic.
>
> Why do you say that? It sure looks like a schematic
> to me. It shows the various components and the circuit
> connections between them.
>
Ralph Mowery
Dec 18, 2012, 11:44:53 AM12/18/12
to
Most digital meters will not bias a diode into conduction. That is why they
have a didoe check on some of them. Even that may not check a microwave
diode.
"Stormin Mormon" <cayoung61***spam...@hotmail.com> wrote in message
news:m3Xzs.68547$s45....@fed06.iad...
have a didoe check on some of them. Even that may not check a microwave
diode.
"Stormin Mormon" <cayoung61***spam...@hotmail.com> wrote in message
news:m3Xzs.68547$s45....@fed06.iad...
> Should be infinite ohms one way, and then reverse the leads, and get some
> where between 2k (about that) ohms the other way. My SWAG at the moment is
> the diode went. If the diode shorted, the cap may be discharged now.
>
> .
> where between 2k (about that) ohms the other way. My SWAG at the moment is
> the diode went. If the diode shorted, the cap may be discharged now.
>
Ralph Mowery
Dec 18, 2012, 11:49:25 AM12/18/12
to
"Smitty Two" <notpub...@cox.net> wrote in message
news:notpublicinfo-AF1...@news.eternal-september.org...
>> > That looks more like a "block diagram" than a schematic.
>>
>> Why do you say that? It sure looks like a schematic
>> to me. It shows the various components and the circuit
>> connections between them.
>>
>
> Seems a little light on detail.
The control board is more like a block diagram, but the other circuit shows
>>
>> Why do you say that? It sure looks like a schematic
>> to me. It shows the various components and the circuit
>> connections between them.
>>
>
> Seems a little light on detail.
all that should be there.
Smitty Two
Dec 18, 2012, 12:06:08 PM12/18/12
to
In article <aPydnZ4FNcULA03N...@earthlink.com>,
I don't see the thermal cutoffs anywhere on that diagram, and I'm the
one who thinks that one of those is the most likely culprit.
one who thinks that one of those is the most likely culprit.
tra...@optonline.net
Dec 18, 2012, 1:30:53 PM12/18/12
to
On Dec 18, 12:06 pm, Smitty Two <notpublici...@cox.net> wrote:
> In article <aPydnZ4FNcULA03NnZ2dnUVZ_qadn...@earthlink.com>,
> "Ralph Mowery" <rmowery28...@earthlink.net> wrote:
>
> > "Smitty Two" <notpublici...@cox.net> wrote in message
fuse on the incoming AC? Sounds like a thermal protection
device to me......
> In article <aPydnZ4FNcULA03NnZ2dnUVZ_qadn...@earthlink.com>,
> "Ralph Mowery" <rmowery28...@earthlink.net> wrote:
>
> > "Smitty Two" <notpublici...@cox.net> wrote in message
> >news:notpublicinfo-AF1...@news.eternal-september.org...
> > >> > That looks more like a "block diagram" than a schematic.
>
> > >> Why do you say that? It sure looks like a schematic
> > >> to me. It shows the various components and the circuit
> > >> connections between them.
>
> > > Seems a little light on detail.
>
> > The control board is more like a block diagram, but the other circuit shows
> > all that should be there.
>
> I don't see the thermal cutoffs anywhere on that diagram, and I'm the
> one who thinks that one of those is the most likely culprit.
What's the "magnetron thermostat" that is right after the
> > >> > That looks more like a "block diagram" than a schematic.
>
> > >> Why do you say that? It sure looks like a schematic
> > >> to me. It shows the various components and the circuit
> > >> connections between them.
>
> > > Seems a little light on detail.
>
> > The control board is more like a block diagram, but the other circuit shows
> > all that should be there.
>
> I don't see the thermal cutoffs anywhere on that diagram, and I'm the
> one who thinks that one of those is the most likely culprit.
fuse on the incoming AC? Sounds like a thermal protection
device to me......
croy
Dec 18, 2012, 7:10:07 PM12/18/12
to
On Tue, 18 Dec 2012 04:49:48 -0500, "Stormin Mormon"
<cayoung61***spam...@hotmail.com> wrote:
>Should be infinite ohms one way, and then reverse the leads, and get some
>where between 2k (about that) ohms the other way. My SWAG at the moment is
>the diode went. If the diode shorted, the cap may be discharged now.
Hehe. What good does "maybe" do??? ;-)
<cayoung61***spam...@hotmail.com> wrote:
>Should be infinite ohms one way, and then reverse the leads, and get some
>where between 2k (about that) ohms the other way. My SWAG at the moment is
>the diode went. If the diode shorted, the cap may be discharged now.
--
croy
gregz
Dec 18, 2012, 8:20:33 PM12/18/12
to
hook 9 volt battery in series with diode and analog meter on high ohms.
On my mirror page.....
http://zekfrivolous.com/faq/sam/micfaq.htm
Greg
mike
Dec 18, 2012, 9:29:52 PM12/18/12
to
I don't remember exactly how many, but a typical multimeter won't
test it...unless it's shorted. Need more volts to forward bias it.
9V battery and a light bulb might do it. Two 9V in series probably will.
Smitty Two
Dec 18, 2012, 10:44:33 PM12/18/12
to
In article
<644d7d36-9a13-4e3f...@hf3g2000vbb.googlegroups.com>,
Perhaps it is, at that. But if that one were shot, there wouldn't be any
power anywhere. My microwave has three thermal cutoffs.
<644d7d36-9a13-4e3f...@hf3g2000vbb.googlegroups.com>,
power anywhere. My microwave has three thermal cutoffs.
Tony Hwang
Dec 18, 2012, 10:55:20 PM12/18/12
to
Magnetron needs high voltage to function. That diode is HV diode some
times in series to raise voltage rating. Usually Magntron buzzes when
working. Is it silent when turned on? Also oven door has multi sequenced
interlock switches which can go bad.
larrymo...@my-deja.com
Dec 19, 2012, 4:02:09 AM12/19/12
to
oven repair: http://www.repairfaq.org/sam/micfaq.htm
Those high voltage diodes will read open with a digital meter because
they're made of several diodes in series to handle the thousands
of volts, and usually digital meter won't apply enough voltage to
make all those diodes conduct. So either try an old-style analog
meter set to a higher ohms scale (x100, x1000, x10,000), or
apply at least 6V - 9V DC through a 1,000 ohm resistor and measure
directly across the diode. If the diode is open, you'll see the
source voltage, but if it conducts, the voltage will be lower.
The big high voltage capacitor has to be discharged before handling
it. It almost always contains a bleeder resistor to do that, but
bleeders fail in use, so assume it's not there. Get a screwdriver
with a plastic handle on it (it's not enough to wrap electrical tape
around a metal handle; the voltage is way too high), and wrap several
turns of BARE solid copper wire around it. Connect the other end of
that wire to a 10,000 ohm, 10 watt resistor, and connected the other
resistor lead securely to bare metal of the oven's chassis. Touch
the tip of the screwdriver to each lead of the capacitor for 30
seconds. Finally, touch the screwdriver shaft to both leads of the
capacitor simultaneously.
Prices for microwaves oven parts vary greatly, and sometimes
electronics parts dealers are cheaper than appliance dealers. Some
of the former include MCM Electronics, Dalbani, Premium Parts, and
Parts Express.
You don't need an exact replacement magnatron, just somethign
compatible mechanically and electrically, and for our Sharp
onvection/microwave ovens I've used L-G magnatrons. Also any
replacement high voltage capacitor should have the same microfarad
(uF) rating as the original because using one with a different
capacitance rating changing it changes the power output roughly
proportionally, meaing the programmed cooking modes may not work
right because they're not calibrated for a higher or lower power.
The magnatron is usually held in place with 3-4 bolts or nuts, and
you absolutely want them to be secured so the magnatron is completely
flush with the mounting surface. Otherwise microwavess will leak past
the brass braided ring seal.
The magnatron has to be cooled with a fan, so be sure that fan works
by feeling for air through the rear vent. There's probably a bimetal
thermostat mounted on the magnatron to shut it off if it gets too
hot, and you may want to replace it because I had one that got stuck
in the on position. They're made with several different temperature
ratings.
I wouldn't turn on a microwave without the cover completely reattached,
including with all its screws, to prevent electrical shock and also
injury in case the capacitor explodes.
mike
Dec 19, 2012, 4:37:15 AM12/19/12
to
On 12/18/2012 7:55 PM, Tony Hwang wrote:
>
>
> Danny D. wrote:
>> On Mon, 17 Dec 2012 22:08:35 -0600, The Daring Dufas wrote:
>>
>>> That's the diode I saw in the pictures and the diagram.
>>> Diodes come in all shapes and sizes. ^_^
>>
>> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>> It has been sitting all day, so maybe by tomorrow it will have
>> discharged.
NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
>
>
> Danny D. wrote:
>> On Mon, 17 Dec 2012 22:08:35 -0600, The Daring Dufas wrote:
>>
>>> That's the diode I saw in the pictures and the diagram.
>>> Diodes come in all shapes and sizes. ^_^
>>
>> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>> It has been sitting all day, so maybe by tomorrow it will have
>> discharged.
DISCHARGED...EVER...!!!
Mine was dead for a week and still had enough charge go explode the wire
I shorted across it.
NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
DISCHARGED...EVER...!!!
If you wanna risk blowing up your Fluke, you can measure the voltage on
the cap...and possibly blow up your meter.
Death is final...don't risk it...no matter how small you think the risk.
Stormin Mormon
Dec 19, 2012, 10:08:57 AM12/19/12
to
It gives you the option of not being killed?
"croy" <ha...@spam.invalid.net> wrote in message
news:nd12d8tm1508hldtv...@4ax.com...
"croy" <ha...@spam.invalid.net> wrote in message
news:nd12d8tm1508hldtv...@4ax.com...
Stormin Mormon
Dec 19, 2012, 10:13:37 AM12/19/12
to
I WONDER. IF YOU TOOK A COTTON SWAB!!!! AND
TAPED THAT TO A ***WOODEN STICK**** AND
THEN DIP!!!! THE SWAB INTO WATER, AND PUT THAT
>>ACROSS<< THE TERMIANLS, THE E*N*E*R*G*Y
OF THE "CAPACITOR" WOULD =DISCHARGE= THROUGH
THE ?MOISTURE? AND THAT WOULD BE ^SAFER^????
"mike" <ham...@netzero.net> wrote in message
news:kas1tf$tjm$1...@dont-email.me...
TAPED THAT TO A ***WOODEN STICK**** AND
THEN DIP!!!! THE SWAB INTO WATER, AND PUT THAT
>>ACROSS<< THE TERMIANLS, THE E*N*E*R*G*Y
OF THE "CAPACITOR" WOULD =DISCHARGE= THROUGH
THE ?MOISTURE? AND THAT WOULD BE ^SAFER^????
"mike" <ham...@netzero.net> wrote in message
news:kas1tf$tjm$1...@dont-email.me...
The Daring Dufas
Dec 19, 2012, 11:18:05 AM12/19/12
to
On 12/19/2012 3:37 AM, mike wrote:
> On 12/18/2012 7:55 PM, Tony Hwang wrote:
>>
>>
>> Danny D. wrote:
>>> On Mon, 17 Dec 2012 22:08:35 -0600, The Daring Dufas wrote:
>>>
>>>> That's the diode I saw in the pictures and the diagram.
>>>> Diodes come in all shapes and sizes. ^_^
>>>
>>> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>>> It has been sitting all day, so maybe by tomorrow it will have
>>> discharged.
>
> NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
> DISCHARGED...EVER...!!!
> Mine was dead for a week and still had enough charge go explode the wire
> I shorted across it.
>
> NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
> DISCHARGED...EVER...!!!
>
> If you wanna risk blowing up your Fluke, you can measure the voltage on
> the cap...and possibly blow up your meter.
>
> Death is final...don't risk it...no matter how small you think the risk.
>
I do believe I mentioned discharging the capacitor through a 110k ohm
> On 12/18/2012 7:55 PM, Tony Hwang wrote:
>>
>>
>> Danny D. wrote:
>>> On Mon, 17 Dec 2012 22:08:35 -0600, The Daring Dufas wrote:
>>>
>>>> That's the diode I saw in the pictures and the diagram.
>>>> Diodes come in all shapes and sizes. ^_^
>>>
>>> Ah. Thanks. I'll figure out how to discharge the capacitor first.
>>> It has been sitting all day, so maybe by tomorrow it will have
>>> discharged.
>
> NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
> DISCHARGED...EVER...!!!
> Mine was dead for a week and still had enough charge go explode the wire
> I shorted across it.
>
> NO!!!! DO NOT UNDER ANY CIRCUMSTANCES ASSUME THAT THE CAP IS
> DISCHARGED...EVER...!!!
>
> If you wanna risk blowing up your Fluke, you can measure the voltage on
> the cap...and possibly blow up your meter.
>
> Death is final...don't risk it...no matter how small you think the risk.
>
1/2 watt resistor. O_o
TDD
mike
Dec 19, 2012, 6:44:03 PM12/19/12
to
is gonna do.
discharging the capacitor through a 110k ohm
> 1/2 watt resistor. O_o
Check my math. Using round numbers...
4000V / 110k is ~36ma.
36ma * 4000v is 145454 mw = 145WATTS peak.
Half watt resistor.
Methinks a metal film might vaporize before that cap
discharged. Carbon might take the energy, if you can find one.
I'd suggest, from the experience level suggested by the tone of the OP,
that your advice is more harmful than helpful.
>
> TDD
>
Ralph Mowery
Dec 19, 2012, 6:56:53 PM12/19/12
to
news:katjh8$icp$1...@dont-email.me...
No need to worry about the power rating, a 1/2 watt resistor is only rated
for less than 500 volts. When the resistor blows apart, the arc will finish
discharging the capacitor.. Big grin..
The microwave is one place that if you do not have any idea what you are
doing and how to do it safely , you beter keep your hands out of it or have
a good insurance policy for your wife and kids to collect on.
Once you pass about 1000 volts, many things that seem to be insulators are
not.
for less than 500 volts. When the resistor blows apart, the arc will finish
discharging the capacitor.. Big grin..
The microwave is one place that if you do not have any idea what you are
doing and how to do it safely , you beter keep your hands out of it or have
a good insurance policy for your wife and kids to collect on.
Once you pass about 1000 volts, many things that seem to be insulators are
not.
The Daring Dufas
Dec 19, 2012, 7:03:02 PM12/19/12
to
over the past four decades. I've never had a problem using a 100k
resistor to discharge a cap in a microwave oven. The danger I would
warn anyone about microwave ovens is to be careful not to expose
yourself to the non-ionizing radiation from the output of an operating
magnetron. Damage to the lens of the eye is quite possible. Of course,
I've also been known to use The Jesus Method to discharge capacitors
and find circuit breakers,........because it's fun. ^_^
TDD
Stormin Mormon
Dec 19, 2012, 8:11:23 PM12/19/12
to
Me, too. As to circuit breakers, I did make a plug
in breaker popper. I don't use it on FPE Stabloc
panels. Ah ain' 'tupid, y'know.
"The Daring Dufas" <the-dari...@stinky-finger.net>
wrote in message news:katkj1$odl$1...@dont-email.me...
in breaker popper. I don't use it on FPE Stabloc
panels. Ah ain' 'tupid, y'know.
"The Daring Dufas" <the-dari...@stinky-finger.net>
wrote in message news:katkj1$odl$1...@dont-email.me...
gregz
Dec 19, 2012, 8:21:56 PM12/19/12
to
resistance. I don't see the cap value listed here. I'd be more inclined to
use at least a 2 watt resistor, but I like sparks.
Greg
mike
Dec 19, 2012, 8:27:32 PM12/19/12
to
On 12/17/2012 9:04 AM, Danny D. wrote:
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no troubleshooting for
> when it doesn't heat. They said the magnetron may need to be replaced:
> Jenn-Air 800-536-6247 Customer Care
>
> A replacement microwave oven has to fit over the electric oven:
> http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
>
> Interestingly, (since it was above the oven) the back sticker says:
> "May be built into a cabinet structure, but not for use adjacent
> to (with 2 feet of) any gas or electric range, cooktop or oven."
> http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
>
> But, that sticker also says:
> This microwave is approved for mounting directly over Jenn-Air
> wall ovens as follows:
> W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
>
> Having never worked on a microwave, I ask what the conventional wisdom is.
> Q: Is it generally feasible to replace just the magnetron?
no,
First you have to determine that it's bad. Then why it failed to
make sure the new one doesn't fail too.
Then you have to find the exact magnetron...at an affordable price.
If you know what you're doing, you might be able to find an equivalent
magnetron...whatever that means...or cobble in a different magnetron.
That's just not practical for most of us.
> Q: Will similarly sized microwave ovens fit (22" widex13"tallx15" deep)?
The only person who can answer that question is the one with the tape
measure
and the candidate oven.
> Q: Is it generally best to stick within the same brand? (e.g., JMC1116AB)?
The standard answer is, microwaves are cheap, go buy a new one.
If you must fit the same hole, your quest is complicated to the extent that
most people won't be able to offer any useful advice.
Call up someone who refurbishes kitchens and ask them.
> This Jenn-Air (model M170B) 1,350 Watt microwave just stopped heating:
> http://www2.picturepush.com/photo/a/11709330/img/11709330.jpg
>
> I called Jenn-Air customer support who said there's no troubleshooting for
> when it doesn't heat. They said the magnetron may need to be replaced:
> Jenn-Air 800-536-6247 Customer Care
>
> A replacement microwave oven has to fit over the electric oven:
> http://www5.picturepush.com/photo/a/11709333/img/11709333.jpg
>
> Interestingly, (since it was above the oven) the back sticker says:
> "May be built into a cabinet structure, but not for use adjacent
> to (with 2 feet of) any gas or electric range, cooktop or oven."
> http://www4.picturepush.com/photo/a/11709332/img/11709332.jpg
>
> But, that sticker also says:
> This microwave is approved for mounting directly over Jenn-Air
> wall ovens as follows:
> W2700 Series Using MK271 Trim Kit, W3000 Series Using MK301 Trim Kit
>
> Having never worked on a microwave, I ask what the conventional wisdom is.
> Q: Is it generally feasible to replace just the magnetron?
no,
First you have to determine that it's bad. Then why it failed to
make sure the new one doesn't fail too.
Then you have to find the exact magnetron...at an affordable price.
If you know what you're doing, you might be able to find an equivalent
magnetron...whatever that means...or cobble in a different magnetron.
That's just not practical for most of us.
> Q: Will similarly sized microwave ovens fit (22" widex13"tallx15" deep)?
The only person who can answer that question is the one with the tape
measure
and the candidate oven.
> Q: Is it generally best to stick within the same brand? (e.g., JMC1116AB)?
The standard answer is, microwaves are cheap, go buy a new one.
If you must fit the same hole, your quest is complicated to the extent that
most people won't be able to offer any useful advice.
Call up someone who refurbishes kitchens and ask them.
The Daring Dufas
Dec 19, 2012, 8:53:44 PM12/19/12
to
TDD
gregz
Dec 19, 2012, 9:39:35 PM12/19/12
to
bleeder, but might be external. I would not trust an internal resistor as
being good.
Ok, a 1 uf cap and 110k resistor tc if .1 sec, so 80% of the voltage will
disappear in .22 seconds. A half watt resistor could smoke.
Greg
Danny D.
Dec 20, 2012, 7:28:13 PM12/20/12
to
On Tue, 18 Dec 2012 20:55:20 -0700, Tony Hwang wrote:
> Usually Magntron buzzes when working.
> Is it silent when turned on?
Hmmm... I don't remember hearing buzzing but there is the loudness of the
> Usually Magntron buzzes when working.
> Is it silent when turned on?
microwave sounding like it's working. The turntable and lights do what
they should, as do the control.
The food just comes out cold.
I'm going to fully test that diode - and report back.
I went to Fryes last night but they didn't have a single 13x22 inch
microwave!
Danny D.
Dec 20, 2012, 7:30:34 PM12/20/12
to
On Wed, 19 Dec 2012 10:18:05 -0600, The Daring Dufas wrote:
> I do believe I mentioned discharging the capacitor through a 110k ohm
> 1/2 watt resistor.
I have some resistors but they're the teeny tiny ones with stripes.
> I do believe I mentioned discharging the capacitor through a 110k ohm
> 1/2 watt resistor.
I will need to go to Radio Shack and get a roughly 100 ohm resistor that
is a half watt or so first then.
I wonder though: Why wouldn't a screwdriver across the terminals work?
(Assuming a non-conductive handle.)
Danny D.
Dec 20, 2012, 7:31:27 PM12/20/12
to
On Wed, 19 Dec 2012 15:44:03 -0800, mike wrote:
> 36ma * 4000v is 145454 mw = 145WATTS peak.
OK. I will read further before going to Radio Shack for that resistor. :)
> 36ma * 4000v is 145454 mw = 145WATTS peak.
Danny D.
Dec 20, 2012, 8:18:59 PM12/20/12
to
On Wed, 19 Dec 2012 01:02:09 -0800, larrymoencurly wrote:
> The electronics great RepairFAQ.org has information about microwave oven
> repair: http://www.repairfaq.org/sam/micfaq.htm
Wow. Lots of good reading there! Thanks.
> The electronics great RepairFAQ.org has information about microwave oven
> repair: http://www.repairfaq.org/sam/micfaq.htm
> Those high voltage diodes will read open with a digital meter ...
> apply at least 6V - 9V DC through a 1,000 ohm resistor and measure
I am getting the test jig set up at Radio Shack & will report back.
> The big high voltage capacitor has to be discharged before handling
OK. Now I see why a bare screwdriver isn't used.
I'll get a 10K ohm 10 Watt resistor at Radio Shack.
> There's probably a bimetal thermostat mounted on the magnatron
> to shut it off if it gets too hot, and you may want to replace
> it because I had one that got stuck in the on position.
Is it supposed to be on or off when the microwave is unplugged?
Mine reads at 0.4 ohms resistance with the microwave unplugged.
mike
Dec 20, 2012, 8:52:39 PM12/20/12
to
Don't use the tip, because it will make a divot in the blade.
In theory, nothing happens.
As a practical matter, it doesn't take a huge transient to
take out the controller board. It's not likely, but why risk it.
The Daring Dufas
Dec 20, 2012, 9:11:41 PM12/20/12
to
shout JESUS! when the bright flash and boom melts the terminals and tip
of your screwdriver. A hundred thousand ohm resistor may pop which is
why you use insulated needle nose pliers and not your fingers to hold
the resistor when you use it to discharge the capacitor. Resistors are
cheaper than fingers. ^_^
TDD
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