Questions re Microwaves

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networkn

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#99512 20-Mar-2012 22:26

Hi There!

We are looking at replacing our microwaves and there are a few things which have left me a little surprised..

We have a Sharp Carosel it's worked fine in it's little cubby whole with ventilation via a gap out the back all the way to the roof.

The two microwaves I have been looking at are a R890NS Sharp and the NN-CS596SQPQ Panasonic..

I spoke to Panny today and they were really wound up about ensuring anything I bought had enough space to ventilate.. 250mm on top, 40mm rear and 50mm on the left and 100mm on the right. I said I didn't even have close to that, and he didn't recommend me buying one! I see Sharp requires 400mm on top of theirs... I don't recall ever being told I needed that much space with our existing one and it has nowhere NEAR that clearance (perhaps 150mm on the top and half that on both sides). Is this just a new thing and am I going to truly break something if I do install it without those clearances (In which case I can't replace my existing for any decent new one).

Also is it worth worrying about radiation or having 5 year old microwaves checked etc?

Are the new Inverter and Convection technologies really any good, or should I just buy a cheap and dirty $200 model? I see they even have STEAM models now! Is that just a marketing thing or worth while?

Also the auto sense functions, how do they work ? Is there a scale in the thing somewhere that works out the weight?

Cheers

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#597989 20-Mar-2012 23:37

i have always used sharp microwaves and they never seem to last more than 4-5 years, they do get a hard life from the kids though, the main reason i keep getting sharp is i always have spare bulbs and other parts when they are needed. and mine just sits on the bench so not sure about air space.

Common sense is not as common as you think.

mattwnz

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#597991 20-Mar-2012 23:43

networkn: Hi There!

We are looking at replacing our microwaves and there are a few things which have left me a little surprised..

We have a Sharp Carosel it's worked fine in it's little cubby whole with ventilation via a gap out the back all the way to the roof.?

The two microwaves I have been looking at are a R890NS Sharp and the?NN-CS596SQPQ Panasonic..?

I spoke to Panny today and they were really wound up about ensuring anything I bought had enough space to ventilate.. 250mm on top, 40mm rear and 50mm on the left and 100mm on the right. I said I didn't even have close to that, and he didn't recommend me buying one! I see Sharp requires 400mm on top of theirs... ?I don't recall ever being told I needed that much space with our existing one and it has nowhere NEAR that clearance (perhaps 150mm on the top and half that on both sides). Is this just a new thing and am I going to truly break something if I do install it without those clearances (In which case I can't replace my existing for any decent new one).

Also is it worth worrying about radiation or having 5 year old microwaves checked etc?

Are the new Inverter and Convection technologies really any good, or should I just buy a cheap and dirty $200 model? I see they even have STEAM models now! Is that just a marketing thing or worth while?

Also the auto sense functions, how do they work ? Is there a scale in the thing somewhere that works out the weight?

Cheers

Have a panasonic invertor, and it has been a poor performer, especially considering how much it cost. The auto cook features have never worked, and it badly overcooks the food if it is used. The magnatron has also died once, and it again has lost a lot of power. It also has no light when you open the door, only when cooking. We were told by panasonic that they didn't know why they were being manufactured with no light on door opening, they just now came that way, and it wasn't a fault. It is now about 5 years old, and wouldn't buy another. Our previous panasonic lasted 15 years, which is why we purchased a panasonic.

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#598019 21-Mar-2012 07:52

We have a "cheap and dirty $200" model. I think it is a Sharp. It is 'installed' in a dedicated space in the kitchen cabinetry, you would be lucky if there is 50mm gap on the sides, maybe 100mm max on the top. Most I see these days are similarly installed.

That said the rear of the cabinet is completely open (similar to behind the fridge cavity) meaning everything can vent out the back/. I doubt clearance would be an issue if you have adequate ventilation such as that. If its completely enclosed then that could be a problem.

As for model, I guess it depends on what you want to use it for. If all your doing is zapping up some 2 minute noodles or reheating leftovers then IMO any basic one would do. If you want to try and zap up a full roast dinner then clearly something with more grunt and more features such as a convector function would be better.

Never had much luck with the 'sensor' myself. Always end up adding a little time.

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#598029 21-Mar-2012 08:25

The panasonics have a lot of electronics vs some of the more basic units, which probably means more to go wrong. We went with the inverter model, (there is a very cheap white inverter one if that suits your kitchen, or a LOT more if you want stainless etc). We only ever really use it for a set time at full power, so it handles this fine.

Re clearances, yes you should aim to adhere to these. Over to you then if it fails prematurely, though they will probably never know if you just return the unit to the shop you purchased it from. Using something outside the manufacturers specs, just because it suits your setup is ok IF you accept that you're now taking the risk and responsibility if it fails, not them.

Byrned

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#598040 21-Mar-2012 08:48

Got a Panasonic and it's in an enclosed space, probably around 40mm air gap around, not counting the other things that seem to get stuffed around it (chopping boards etc).

Seems to be fine although it never really gets a workout.

And for some unsolicited advice, the best place for cooking anything to an even temperature in a microwave is at the edge, where it will evenly rotate, and not in the middle where one part of the item is always exposed to the same amount of energy!

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#598051 21-Mar-2012 08:59

networkn: Also is it worth worrying about radiation or having 5 year old microwaves checked etc?

Are the new Inverter and Convection technologies really any good, or should I just buy a cheap and dirty $200 model? I see they even have STEAM models now! Is that just a marketing thing or worth while?

Also the auto sense functions, how do they work ? Is there a scale in the thing somewhere that works out the weight?

Cheers

my 1/2 cents?

definitely worth worrying about radiation. you don't want to be cooked do you? decay is exponential over distance anyhow, so stand clear should be fine ... defintiely don't trust old ones, but it's actually hard to know which new ones are better! having said that mobile phones transmit microwaves too ...

if you want to produce a nigella lawson dish using a microwave, then get the best whatever that ACTUALLY works ... the cheap ones do not heat evenly in terms of the 3D space of your meal, and in terms on firing time eg 200W down from 1000W may actually mean it is firing 1/5th of the time at 1000W etc ...

but if you want to reheat yesterday's dinner and don't care too much about your instant noodles i'd say just worry about the radiation leaks ... but i can't give any more on that i'm afraid ... I use a Swedish Whirlpool

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#598151 21-Mar-2012 12:16

Convection microwaves are excellent IMHO. Not for the combined micro+convection really, but just because you have a small convection oven right there without having to heat up the full size one.

I wouldn't buy just a plain microwave again, always go for the convection.

Just remember, no metal in microwave mode, no plastic in convection or grill mode! I have some a couple of ceramic dishes for the odd occasion I want to use the micro+convection or micro+grill (or a program using one mode after the other).

I can convection cook , say, a tray of sausages @180 degrees in 30 minutes, it'd take at least 1/2 that time just to heat up the big oven, and then you've got a big-oven load of waste heat at the end of it. And it's good even heat because the turntable still turns and you have a fan in there too, no real hot-spots.

I presently have one from The Warehouse which I bought on special last year
http://www.thewarehouse.co.nz/red/catalog/product/Sanyo-Convection-Microwave-with-Grill-25L?SKU=1380442
it works well enough, however the LCD loses it's first digit sometimes and the lamp blew rather prematurely. I can't be bothered taking it back for that though (besides I don't know where the receipt is), a judicious upwards whack with the heel of my palm fixes the LCD.

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richms

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#598297 21-Mar-2012 16:48

Convection ones are better because they are actually stainless, not just stainless on the front and still painted metal inside like most "stainless" microwave ovens.

Richard rich.ms

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#598343 21-Mar-2012 19:23

networkn: Hi There!

I spoke to Panny today and they were really wound up about ensuring anything I bought had enough space to ventilate.. 250mm on top, 40mm rear and 50mm on the left and 100mm on the right. I said I didn't even

I noticed this requirement a couple of years ago when we replaced our Microwave and wasnt previously aware of it either - but apparently neither are kitchen designers because our Microwave hole only had around 50mm on the sides and maybe 100mm at the top - and it wasnt vented and had a back panel.

I was a bit worried about it but ended up putting the new Microwave there anyway (nowhere else for it to go!) and two years later its still fine - it gets used daily - of course your millage may vary. The microwave from was the Warehouse, I just looked but it doesnt have a brand on the front - I think it might be a Sharp.

Also, DSE used to sell a Microwave leakage detector - I've got one and have used it a few times around the microwave - the needle doesnt really budge so either my Microwave is fine or my meter is busted - gives me some piece of mind (I still stand back when it’s operating tho).

richms

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#598347 21-Mar-2012 19:29

I had one of thise. nothing from the microwave but would max out on my old 5110 at about 200mm

Richard rich.ms

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#598372 21-Mar-2012 20:34

Regarding auto weight, I believe it is done by measuring the turn table start-up current draw.

The critical part of any microwave is how good the door seal is. Now you might say but there is no rubber seal, and you are correct. There is a plastic strip inserted into the door. This is a dielectric for a wave guide which is tuned to exactly a quarter wavelength of the magnetron so waves travel into it and reflects out at 180 degrees shifted so you get cancellation. Now the question is do you trust a cheap microwave to do that, and to keep on doing it after 10 years of use?

The clearance can be only for 3 reasons I can think of:
1) regulation to guarantee the minimal amount of leakage does not cause trouble.
2) regulation so that if the food inside catches fire of you have metal objects inside or you copy Braniac, there will be enough clearance to contain the fire.
3) air flow for the air intake grills.
Our Samsung has been working really well for the past 11 years, always with something close to the right hand side where the air intake grill is. It was repaired under warranty for a failed capacitor and since the display would fog up if we make anything producing steam, but amazingly no failure while doing this for more than 9 years. Probably because condensed steam is clean, no ions, so no corrosion path (this is what Gore Tex vents rely on).

Google the brands you consider buying, there are web sites where customers can complain about their products (think it is called Whirlpool in AU, and there are a couple in UK). And avoid The Warehouse, you do not buy reliable quality from them. Without investigating I would get Samsung or maybe Sharp, they make parts for other manufacturers so should know what they do.

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#598384 21-Mar-2012 21:05

Our Sharp has had a dead LCD display for the last 3 years...
But as we use it for simple re-heating, it's not an issue for us.
I do like the microwave (not sure what brand) where the plate doesn't rotate, instead the microwave effectively revolves around your meal. Less moving parts to be exposed to spilt food etc.

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#598390 21-Mar-2012 21:19

I swear by my Panasonic inverter, the light does come on when the door opens. Perhaps it varies between models.

Aside from the size of the oven, moving to an inverter was night and day. My foods splatter less and cold spots are few and far between. the only annoying thing is the electronics heat up quickly and forces the microwave fan to continue running. The old technology only turned on or off the magnetron when power levels are set. A lower power meant a longer interval between the magnetron switching. For inverter models, the magnetron is always on but varies according to power.

As for as radiation, I would be more concerned with holding a cellphone right next to my head first before even entertaining the fact of any negative effects of using a microwave. At most, a leaking microwave will cook your cells (literally) due to the water content of the cell oscillating creating the friction, i.e. heat. There is no 'lingering' radiation when the magnetron stops

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#598407 21-Mar-2012 21:46

Thanks for all the good advice. I think Panasonic is off the table due to the number of complaints in the comments of the recent 2012 microwave review line up.

mattwnz

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#598421 21-Mar-2012 22:18

khull: I swear by my Panasonic inverter, the light does come on when the door opens. Perhaps it varies between models.

Aside from the size of the oven, moving to an inverter was night and day. My foods splatter less and cold spots are few and far between. the only annoying thing is the electronics heat up quickly and forces the microwave fan to continue running. The old technology only turned on or off the magnetron when power levels are set. A lower power meant a longer interval between the magnetron switching. For inverter models, the magnetron is always on but varies according to power.

As for as radiation, I would be more concerned with holding a cellphone right next to my head first before even entertaining the fact of any negative effects of using a microwave. At most, a leaking microwave will cook your cells (literally) due to the water content of the cell oscillating creating the friction, i.e. heat. There is no 'lingering' radiation when the magnetron stops

Yes I think different models had the 'no light' feature, as our older panansonic has a door light. The new one though is one of the expensive stainless steel ones.

I am just wondering why they have these minimium clearances around the sides and tops, as in my case, there are no vents on the sides and top. the only vent is at the back, so I would think that as long as it was well vented where the vents were, it would be fine. But perhaps it has to do with radiation, and the gap is to prevent energy going into heat the surrounding surfaces, which could cause failure of the magnatron? Anyone know?

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