[Andrew Gabriel]

In article ,
Adam Funk writes:
On 2012-04-27, Andrew Gabriel wrote:

In article ,
Adam Funk writes:

Note 1. "No user serviceable parts" indeed. Buy a new appliance,
sucker.

Well, it means it should be serviced by a service centre, and
there are some reasons.

Including the fact that you can (illegally) fit a microwave oven in
your black bin & buy another for the same price as having the old one
fixed.

However, I expect you did fix and test
the door interlock switches as required before replacing a
microwave's mains input fuse...

TBH, I checked the door afterwards, & there was nothing wrong with it.

What did you check?

One of the door interlock microswitches deliberately shorted out
the supply, because the two microswitches disagreed on the door
being open or closed, so the interlock failed. There can't be
"nothing wrong with it". It may seem to just work by replacing
the fuse, but that's not good enough. There's still the original
fault to find, and there's possibly a second fault now due to
the microswitches having been used to crowbar the supply,
rendering one or both microswitches inoperative. These two faults
can appear to cancel each other out, but they don't - it means
the door interlock failed, and you've possibly now also lost the
redundancy checking on the door interlock so it can't detect the
interlock failed.

That's partly why it says "No user serviceable parts".

Interlock failure can be caused by one of the microswitches not
working, or the catch mechanism or door hinge wearing out, or the
oven being bashed or bent so the door is out of true with risk of
microwave leakage. In the case of wearing out, it might first
show itself either when closing the door very slowly, or when
slamming it.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[Adam Funk[_3_]]

On 2012-05-01, Andrew Gabriel wrote:

In article ,
Adam Funk writes:

TBH, I checked the door afterwards, & there was nothing wrong with it.

What did you check?

I don't remember. This was about 10 years ago, & my father, who has
more practical experience of appliance repair, was involved.

One of the door interlock microswitches deliberately shorted out
the supply, because the two microswitches disagreed on the door
being open or closed, so the interlock failed. There can't be
"nothing wrong with it". It may seem to just work by replacing
the fuse, but that's not good enough. There's still the original
fault to find, and there's possibly a second fault now due to
the microswitches having been used to crowbar the supply,
rendering one or both microswitches inoperative. These two faults
can appear to cancel each other out, but they don't - it means
the door interlock failed, and you've possibly now also lost the
redundancy checking on the door interlock so it can't detect the
interlock failed.

That's partly why it says "No user serviceable parts".

Interlock failure can be caused by one of the microswitches not
working, or the catch mechanism or door hinge wearing out, or the
oven being bashed or bent so the door is out of true with risk of
microwave leakage. In the case of wearing out, it might first
show itself either when closing the door very slowly, or when
slamming it.

I appreciate the explanation & I'll save it for future reference.

[Brian Gaff]

I had a philips microwave that rusted through on the bottom lip of the drop
down door, it almost fell off the hinge. The paint covered up the rust!
Brian

--
From the Sofa of Brian Gaff Reply address is active
"Adam Funk" wrote in message
...
On 2012-05-01, Andrew Gabriel wrote:

In article ,
Adam Funk writes:

TBH, I checked the door afterwards, & there was nothing wrong with it.

What did you check?

I don't remember. This was about 10 years ago, & my father, who has
more practical experience of appliance repair, was involved.

One of the door interlock microswitches deliberately shorted out
the supply, because the two microswitches disagreed on the door
being open or closed, so the interlock failed. There can't be
"nothing wrong with it". It may seem to just work by replacing
the fuse, but that's not good enough. There's still the original
fault to find, and there's possibly a second fault now due to
the microswitches having been used to crowbar the supply,
rendering one or both microswitches inoperative. These two faults
can appear to cancel each other out, but they don't - it means
the door interlock failed, and you've possibly now also lost the
redundancy checking on the door interlock so it can't detect the
interlock failed.

That's partly why it says "No user serviceable parts".

Interlock failure can be caused by one of the microswitches not
working, or the catch mechanism or door hinge wearing out, or the
oven being bashed or bent so the door is out of true with risk of
microwave leakage. In the case of wearing out, it might first
show itself either when closing the door very slowly, or when
slamming it.

I appreciate the explanation & I'll save it for future reference.

[Andrew Gabriel]

In article ,
"Brian Gaff" writes:
I had a philips microwave that rusted through on the bottom lip of the drop
down door, it almost fell off the hinge. The paint covered up the rust!

Microwave oven cavities rusting through the bottom due to spillage
and/or condensation can be an issue, and is something to be checked
when inspecting/testing them.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[Adam Funk[_3_]]

On 2012-05-11, Andrew Gabriel wrote:

In article ,
"Brian Gaff" writes:
I had a philips microwave that rusted through on the bottom lip of the drop
down door, it almost fell off the hinge. The paint covered up the rust!

Microwave oven cavities rusting through the bottom due to spillage
and/or condensation can be an issue, and is something to be checked
when inspecting/testing them.

Is that going to blow the fuse?
;-)

[Andrew Gabriel]

In article ,
Adam Funk writes:
On 2012-05-11, Andrew Gabriel wrote:

In article ,
"Brian Gaff" writes:
I had a philips microwave that rusted through on the bottom lip of the drop
down door, it almost fell off the hinge. The paint covered up the rust!

Microwave oven cavities rusting through the bottom due to spillage
and/or condensation can be an issue, and is something to be checked
when inspecting/testing them.

Is that going to blow the fuse?
;-)

No (unless it affects the door position or door catches).

Can cause arcing and high heating at the site, as well as
microwave leakage of course.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]