A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.
--

Mike

Mike Halmarack formulated the question :
Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

No, they are entirely different technologies, different methods to
create heat.

On 30/10/2020 09:08, Harry Bloomfield wrote:
Mike Halmarack formulated the question :
Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

No, they are entirely different technologies, different methods to
create heat.

True, but both are "high power". Perhaps there is a 10A fuse or similar
in the "high power" circuitry in the microwave which has blown. However,
fuses usually blow for a reason, and finding that reason could be
difficult. It is also inherently dangerous; even if disconnected from
the mains microwave ovens can retain a high voltage in the magnetron
drive circuitry capacitor for some time. That capacitor would need to be
completely discharged carefully before the OP went digging around inside
for a fault (that does not include putting an insulated screwdriver
across its terminals!).

--

Jeff

On 30/10/2020 08:52, Mike Halmarack wrote:
A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

The grill, and convection mode heating are both resistive heaters.

I am slightly surprised if the grill is working that it doesn't also
generate some lower heat in the convection oven mode.

The microwave unit is entirely separate and has some seriously lethal
voltages available on capacitors in its circuitry. If you need to ask
the question above then delving into it is highly inadvisable.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.

I think it has probably become Wee scrap.

--
Regards,
Martin Brown

On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!
--

Mike

On 30/10/2020 11:32, Mike Halmarack wrote:
On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!


If you do decide to scrap it then the turntable motor in my
17-YO Sharp Combi-micro-oven has failed, so I would be interested
in acquiring it (the motor) for a suitable price.

Not really as in a pure Microwave its the microwaves that heat the food, in
a convection oven you can, assumedly, just use that part with no microwave
in the mix. These tend to use normal elements and a fan!

Sounds like it might be a control board issue. One assumes the display is
still telling you all is well etc?
I guess the parts probably have protection for each device. On the
Microwave side its normally a diode that goes and trips the fuse. I'm
assuming it no longer hums loudly when microwave is used? It would seem odd
if the convection oven was on the same fuse, but I guess it could be, which
would shut both off, and you would need to find out which one is the fault.
Did the element short or did the microwave psu die?
Strange that the other heating element is separate though..
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Mike Halmarack" wrote in message
...
A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.
--

Mike

No that may well weld the screwdriver to it in any case!

Many do have a high value bleed resistor though, so it does discharge
gradually over time.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Jeff Layman" wrote in message
...
On 30/10/2020 09:08, Harry Bloomfield wrote:
Mike Halmarack formulated the question :
Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

No, they are entirely different technologies, different methods to
create heat.

True, but both are "high power". Perhaps there is a 10A fuse or similar in
the "high power" circuitry in the microwave which has blown. However,
fuses usually blow for a reason, and finding that reason could be
difficult. It is also inherently dangerous; even if disconnected from the
mains microwave ovens can retain a high voltage in the magnetron drive
circuitry capacitor for some time. That capacitor would need to be
completely discharged carefully before the OP went digging around inside
for a fault (that does not include putting an insulated screwdriver across
its terminals!).

--

Jeff

Yeah right, plastic silver.

Don't expect more than 5 years from it though. My current one is an
exception to the normal rule.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Mike Halmarack" wrote in message
...
On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!
--

Mike

On Fri, 30 Oct 2020 19:22:34 -0000, "Brian Gaff \(Sofa\)"
wrote:

Yeah right, plastic silver.

Don't expect more than 5 years from it though. My current one is an
exception to the normal rule.
Brian

On Fri, 30 Oct 2020 14:55:52 +0000, Andrew
wrote:

On 30/10/2020 11:32, Mike Halmarack wrote:
On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!


If you do decide to scrap it then the turntable motor in my
17-YO Sharp Combi-micro-oven has failed, so I would be interested
in acquiring it (the motor) for a suitable price.

On Fri, 30 Oct 2020 14:55:52 +0000, Andrew
wrote:

On 30/10/2020 11:32, Mike Halmarack wrote:
On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!


If you do decide to scrap it then the turntable motor in my
17-YO Sharp Combi-micro-oven has failed, so I would be interested
in acquiring it (the motor) for a suitable price.

I think I might've just emailed you.
--

Mike

On Fri, 30 Oct 2020 19:22:34 -0000, "Brian Gaff \(Sofa\)"
wrote:

Yeah right, plastic silver.

I new we were heading for trouble when there were no grey cars
anymore.

Don't expect more than 5 years from it though. My current one is an
exception to the normal rule.
Brian

My earlier, similar Sharp model lasted about 20 years.
--

Mike

On Fri, 30 Oct 2020 19:17:32 -0000, "Brian Gaff \(Sofa\)"
wrote:

Not really as in a pure Microwave its the microwaves that heat the food, in
a convection oven you can, assumedly, just use that part with no microwave
in the mix. These tend to use normal elements and a fan!

Sounds like it might be a control board issue. One assumes the display is
still telling you all is well etc?
I guess the parts probably have protection for each device. On the
Microwave side its normally a diode that goes and trips the fuse. I'm
assuming it no longer hums loudly when microwave is used? It would seem odd
if the convection oven was on the same fuse, but I guess it could be, which
would shut both off, and you would need to find out which one is the fault.
Did the element short or did the microwave psu die?
Strange that the other heating element is separate though..
Brian

Thanks Brian, but I capitulated.

On Friday, 30 October 2020 08:52:10 UTC, Mike Halmarack wrote:

A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.

Microwaves don't run on a heat source.
There isn't normally a fuse that runs 2 out of 3 of the heating modes.

The caution about lethal voltage is true, but it's not hard to de-lethal it. However you still need to understand about microwaves and safety to do the job.

You've now got a spare tt motor, spare fan, MOT which has many uses, some quite interesting, and a magnetron that's seldom useful and likely quite toxic. And often a VFD that you can turn into an exotic radio. And a spare bit of mica.


NT

On Sat, 31 Oct 2020 15:56:39 -0700 (PDT), wrote:

On Friday, 30 October 2020 08:52:10 UTC, Mike Halmarack wrote:

A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.

Microwaves don't run on a heat source.
There isn't normally a fuse that runs 2 out of 3 of the heating modes.

The caution about lethal voltage is true, but it's not hard to de-lethal it. However you still need to understand about microwaves and safety to do the job.

You've now got a spare tt motor, spare fan, MOT which has many uses, some quite interesting, and a magnetron that's seldom useful and likely quite toxic. And often a VFD that you can turn into an exotic radio. And a spare bit of mica.


NT

Sounds fascinating. I did pull it to bits to make carrying it
downstairs less troublesome. The magnetron was the heaviest part and
by it's name and nature most interesting. Toxicity seems to be the
most discussed aspect on YouTube.
Is there a special dumping method for one of these?
--

Mike

On Fri, 30 Oct 2020 14:55:52 +0000, Andrew
wrote:

On 30/10/2020 11:32, Mike Halmarack wrote:
On Fri, 30 Oct 2020 08:52:08 +0000, Mike Halmarack
wrote:

Thanks for the advice chaps.
"Wee scrap" puts it in a nutshell I think.
Ordered a new one but may play about with the old on in the garage.
I'm quite lucky in a way because the old model was mere stainless
steel, whereas the new model is "Silver"!


If you do decide to scrap it then the turntable motor in my
17-YO Sharp Combi-micro-oven has failed, so I would be interested
in acquiring it (the motor) for a suitable price.

No luck yet at cleverly guessing your email address Andew.
--

Mike

Mike Halmarack wrote:
On Sat, 31 Oct 2020 15:56:39 -0700 (PDT), wrote:

On Friday, 30 October 2020 08:52:10 UTC, Mike Halmarack wrote:

A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.
Microwaves don't run on a heat source.
There isn't normally a fuse that runs 2 out of 3 of the heating modes.

The caution about lethal voltage is true, but it's not hard to de-lethal it. However you still need to understand about microwaves and safety to do the job.

You've now got a spare tt motor, spare fan, MOT which has many uses, some quite interesting, and a magnetron that's seldom useful and likely quite toxic. And often a VFD that you can turn into an exotic radio. And a spare bit of mica.


NT

Sounds fascinating. I did pull it to bits to make carrying it
downstairs less troublesome. The magnetron was the heaviest part and
by it's name and nature most interesting. Toxicity seems to be the
most discussed aspect on YouTube.
Is there a special dumping method for one of these?

Beryllia is dangerous when sanded, ground, or otherwise
turned into a powder and inhaled. If a product has such
a substrate in it, there should be a warning sticker on it,
a skull and crossbones. I've seen it used in lab equipment,
which is where I saw the markings. (And part of informing
everyone at work, is so our resident Dremel Fool would know the
rules. Some people will Dremel just about anything given
a chance.) The only microwave oven I've thrown away, I
don't recollect seeing anything like that inside.

https://en.wikipedia.org/wiki/Beryllium_oxide

"Safety

BeO is carcinogenic in powdered form and may cause a chronic allergic-type
lung disease berylliosis. Once fired into solid form, it is safe to handle
if not subjected to machining that generates dust, clean breakage releases
little dust but crushing or grinding actions can pose a risk.[13]

Beryllium oxide ceramic is not a hazardous waste under federal law in the USA.
"

You would not use an angle grinder or a Dremel on it.

https://www.aaren-technology.com/pdf...lium-oxide.pdf

I gather it's the white bit in the picture.

https://www.americanberyllia.com/img/microwave2.png

If you take your electronics to an electronics recycler,
they probably have a disposal service just for microwave ovens
at a guess. For the older microwaves, the oil filled cap
should probably have the oil drained before further disposal.
I have no idea how much oil is inside. I put the cover back
on my microwave oven, before heading off to dispose of it.
The sound the microwave made, there was no need to do any
root cause on it. On mine you could tell something shorted
out, as the transformer let out a rather loud hum for two seconds.

Paul

On Sunday, 1 November 2020 12:11:55 UTC, Mike Halmarack wrote:
On Sat, 31 Oct 2020 15:56:39 -0700 (PDT), tabbypurr wrote:
On Friday, 30 October 2020 08:52:10 UTC, Mike Halmarack wrote:

A very old friend, my Sharp combination microwave, convection oven and
grill lost functionality last night. Currently the grill heats as
usual, the fan blows and the turntable rotates but neither the
convection oven nor the microwave produce any heat.

When working do they share the same heat source?

I looked at some YouTube videos showing an "easily fixable" fuse
problem but these videos are about simpler machines.

I changed the turntable drive motor a couple of months ago with quite
pricey spares, so I feel quite committed to keeping this model going.
If they do share the same heat source I'd be more encouraged to delve.

Microwaves don't run on a heat source.
There isn't normally a fuse that runs 2 out of 3 of the heating modes.

The caution about lethal voltage is true, but it's not hard to de-lethal it. However you still need to understand about microwaves and safety to do the job.

You've now got a spare tt motor, spare fan, MOT which has many uses, some quite interesting, and a magnetron that's seldom useful and likely quite toxic. And often a VFD that you can turn into an exotic radio. And a spare bit of mica.


NT

Sounds fascinating. I did pull it to bits to make carrying it
downstairs less troublesome. The magnetron was the heaviest part and
by it's name and nature most interesting. Toxicity seems to be the
most discussed aspect on YouTube.
Is there a special dumping method for one of these?

Take it to the dump. Or a scrap place.
The heaviest bit is usually the transformer, but not with invertor ovens, which are a small minority.

Paul is right about the use of beryllium being debatable. I'd rather not find out the hard way, it's not pleasant stuff.


NT