Microwave RIP?

Woolsery

Section62 said:

Woolsery said:

Bendy, our Panasonic Multi Function 'went' last week, though no bang audible above the noise our grandchildren make. When I opened it up to look for the high voltage fuse, I couldn't see one, so gave up without any extensive dismemberment. The thing is 12 years old after all and I have £300 of nectar points going mouldy....

Could you confirm there's no HV fuse on these. They still look much the same visually.I'd expected the fuse to be easily acessible near the mains lead entry, but if it's likely to be somewhere else I'm willing to take a look with due care about stuff like capacitors.

It's a NN-CF760M or NN -CF750W

Sorry kuepper for the hijack! 

I'd suggest Bendy (or anyone else) would be very unwise to offer you advice on repairing your microwave.  Anyone who doesn't know where to look for the HV fuse doesn't have the required level of competence to replace one safely.

These things can kill people.  Don't mess around with them.

As above, "With due care." I'm not interested in anything other than HV fuse replacement. I'm competent to do that and keep myself safe from stored energy in capacitors etc, again as indicated clearly in my post.

But Bendy can make up his own mind and PM me if he prefers. Thanks for your concern.

Section62

Woolsery said:

Section62 said:

Woolsery said:

Bendy, our Panasonic Multi Function 'went' last week, though no bang audible above the noise our grandchildren make. When I opened it up to look for the high voltage fuse, I couldn't see one, so gave up without any extensive dismemberment. The thing is 12 years old after all and I have £300 of nectar points going mouldy....

Could you confirm there's no HV fuse on these. They still look much the same visually.I'd expected the fuse to be easily acessible near the mains lead entry, but if it's likely to be somewhere else I'm willing to take a look with due care about stuff like capacitors.

It's a NN-CF760M or NN -CF750W

Sorry kuepper for the hijack! 

I'd suggest Bendy (or anyone else) would be very unwise to offer you advice on repairing your microwave.  Anyone who doesn't know where to look for the HV fuse doesn't have the required level of competence to replace one safely.

These things can kill people.  Don't mess around with them.

As above, "With due care." I'm not interested in anything other than HV fuse replacement. I'm competent to do that and keep myself safe from stored energy in capacitors etc, again as indicated clearly in my post.

But Bendy can make up his own mind and PM me if he prefers. Thanks for your concern.

Again, and in the nicest possible way, it is axiomatic that someone who doesn't know what a High Voltage fuse looks like and where it is located doesn't have the technical competence to replace it.

The dangers within a microwave oven are not limited to stored energy in capacitors.  Being able to identify basic components (e.g. the high voltage fuse) and understanding where they are and how they work is vital to making safe repairs.

People giving advice on high-risk repairs (along with this website) could be held liable in the event you manage to electrocute yourself or your grandchildren, or burn your house down.

Attempting a DIY repair of a 12 year old microwave on the basis of advice from an internet forum and without reference to the manufacturer's service manual is extremely dangerous.

Bendy_House

Again, a conundrum. Do I not offer guidance on how to swap an old room 'stat with a modern equivalent, because mains voltages are involved? And am I - gulp - culpable should someone 'cute themselves in the process when following my advice?

I just don't know. 

Pretty sure MSE has a disclaimer, but that won't save an 'incompetent' or careless person.

Woolsery, I don't know anything specific about that model, or Panasonic's in general, but the HV fuses I've dealt with have been in-line, in typical plastic fuse holders, possibly coming from the caps to the magna. 

Woolsery

I didn't say I had no knowledge of what a fuse looked like. I'd had a cursory look and not seen it. From other info elsewhere I've reason to believe it might not be in the most logical place where I've looked. It seems unlikely it doesn't exist. I believe someone misused the machine, causing it to blow, but I've no way of confirming that.

But you're right, unofficial information is regarded as dangerous today and Bendy needn't feel in a difficult position now. I've found the details elsewhere. It's a good thing there still is an 'elsewhere.' I know that  replacing the fuse may not solve anything, and if that's the case it's the end of the road. I said all that. Keeping stuff out of the tip if possible is important to me.

Woolsery

Bendy_House said:

Woolsery, I don't know anything specific about that model, or Panasonic's in general....

Actually, I think this sort of thing is best dealt with visually, ideally a video, photos etc and I've found something, so don't worry.

I'm from a generation where we had to do stuff ourselves or do without; hence changing multiple engines, gearboxes etc and re-wiring 2 houses before I was 30. Now I can afford to do otherwise but self-reliance dies hard!

Section62

Bendy_House said:

Again, a conundrum. Do I not offer guidance on how to swap an old room 'stat with a modern equivalent, because mains voltages are involved? And am I - gulp - culpable should someone 'cute themselves in the process when following my advice?

I'd suggest there is some level of risk assessment needed - if someone gives wrong advice and that leads to death or injury they ought to expect to have some degree of comeback from the authorities.  If they give incomplete advice then the familiar 'reasonableness' will be a factor.  Would you expect someone using a consumer-orientated website to know how to safely discharge power circuit capacitors (even if they say they do) when they also say they have been looking for the HV fuse near the mains cable entry?  The issue is none of us here really know the competence of people seeking advice. (not to be confused with thinking they are 'incompetent' and the negativity that goes with that)

The risk level of changing a room stat is somewhat lower than working on the innards of a microwave.  Correctly isolating the mains supply to the central heating, and verifying that with a meter, should be enough - although that doesn't entirely rule out the possibility (like one I discovered this week) that the CH system is energised via two FCU's on different rings.  On a different thread some time ago I said that control circuits need special care because safe/not-safe is difficult to determine, and there's very little limit to the dangerous things people sometimes do.  I'd stand by that comment.

Bendy_House said:

I just don't know. 

Pretty sure MSE has a disclaimer, but that won't save an 'incompetent' or careless person.

I don't think a disclaimer does much good... if you are legally liable then you are legally liable.

I'd suggest a useful parallel is the situation with medical advice ('banned' here).  In theory there may be some 'safe' medical advice, but it is such a difficult area it is usually best to stick with advising people to consult a doctor or 111.  That could be because we collectively regard the medical profession as one clearly needing qualifications.  But on a scale of risk, poking around inside a device with voltages of (say) 4.2kV is very likely to be more dangerous than applying some antiseptic and a plaster to a cut... yet 'advice' on one is (possibly?) allowed and the other (by the 'rules') isn't.

Section62

Woolsery said:

Keeping stuff out of the tip if possible is important to me.

I agree with that, and follow the same approach myself.

However, one thing more important to me is keeping people out of the ground.

In the industry I work in I've known/seen too many people killed or seriously injured to believe that taking risks is worthwhile.  The first rule is to know your limits.

MalMonroe

Hi! 

Jumping in to say if it isn't under guarantee then I'd just replace it.

There's some info here - (No. 6)

https://applianceexpresstx.com/microwave-repair/the-10-most-common-microwave-repair-problems/

I just replaced mine because I didn't like the way the paint was beginning to peel on the inside. First little bubbles and then small patches of peeling. It wasn't that old but wasn't that expensive either. Apparently average expected lifespan of a microwave oven is between 6 and 10 years.

I wouldn't try to fix anything on a microwave myself, particularly as there's usually a bossy notice telling me not to remove cover. I wouldn't dare!  I know others do but it's not for me.   

MalMonroe

Woolsery said:

Bendy_House said:

Woolsery, I don't know anything specific about that model, or Panasonic's in general....

Actually, I think this sort of thing is best dealt with visually, ideally a video, photos etc and I've found something, so don't worry.

I'm from a generation where we had to do stuff ourselves or do without; hence changing multiple engines, gearboxes etc and re-wiring 2 houses before I was 30. Now I can afford to do otherwise but self-reliance dies hard!

I'm also from that generation BUT times and manufacturing processes move on. For example, simple things like changing plugs - which I could do until the cows came home - just isn't necessary any more and electrical goods are far more sophisticated than they were 'back in the day'. Rewiring a house now requires a certified and qualified worker, whose work is then signed off by yet another certified and qualified worker. 

Self-reliance is a great thing but it isn't always sensible, especially in these far more sophisticated times.

As for keeping stuff out of the tip - you can call upon disposal experts who break items down and reuse parts. My old microwave has just gone that way. Not to a tip but to a recycle plant. That's something else that's different from the 'good old days'. Which weren't really all that good when I come to think about it. I'd rather be here, now, with all the modern technology. 

Section62

MalMonroe said:

There's some info here - (No. 6)

https://applianceexpresstx.com/microwave-repair/the-10-most-common-microwave-repair-problems/

That's a USA site, so some of the advice is not necessarily applicable to UK equipment.

It also contains useless/inaccurate/dangerous advice... e.g. the advice under item 5 is dangerously wrong.  You should NEVER attempt to force the door open if the microwave oven doesn't stop cooking at the end of the timed period.  (This ought to be obvious to anyone who understands the dangers of microwave energy).