What is the life expectancy of an induction hob?

[easternangle]

Hi, is there any one here who can help a newbie with a problem? I bought a house with a recently installed kitchen four years ago. The induction hob was a well-known make (De Dietrich) and the people installing the kitchen, reputable. I've cooked on it most days since, and it's not been bad, though not my favourite cooking method. Now the hob has suddenly broken - that is, half the rings no longer work. Looking online it would seem that repairing induction hobs is both a tricky and expensive process. I'm not sure what to do - being not necessarily in favour of repair if it's too costly. I'm also pretty shocked - I have never owned any form of cooker in the past that actually BROKE- they've all been retired due to extreme old age. My questions are, if anyone knows: What is the life expectancy of an induction hob? Why did mine just stop working? Are there things I can check myself? What are their specific benefits over other hobs to justify the price (apart from toys-for-boys status)? Any help most gratefully accepted!

[Derek ^]

[...]

For the last 4 replacements I haven't had a built in oven (electric = gas) that has lasted as long as 4 years.

It is high power electronics built down to a price. OTOH microwave cookers seem to last OK.

Probably failure of a component.

Probably not unless there are fuses you can identify and check.

Food doesn't burn onto them (much)

I had one and the controls were most perplexing it had a continuously variable "power" control and also power cycling (duty ratio) control. Nothing to see, no real way to determine the rate of application of heat.

It got cracked and I didn't replace it.

Plenty of cheap hob places on t' internet, such as :

DG

[Christian McArdle]

Controllability of gas. Cleanability of ceramic. Plus the other advantages/disadvantages of electric vs gas.

Christian.

[Mr Fixit]

EH what's does "Controllability of gas" have to do with the benefit of having an induction hob

[Andy Wade]

Do these induction hobs work at 50 Hz, or is there some kind of inverter involved, producing power at a higher frequency?

[Rob Morley]

It cools down the moment you reduce the power, unlike an electric ring which will sit under the pan being hot for a while.

[Christian McArdle]

An induction hob responds instantly like a gas hob. Other forms of electric cooker (i.e. sealed plate, ring, ceramic and halogen) have a response time of ten seconds or longer.

Christian.

[Mr Fixit]

I understand that but the OP question was not the benefit of "not" have an induction hob but what was the benefits of an induction hob

[Rob Morley]

I'm talking about an induction hob. Maybe I should have phrased it more carefully and instead of "electric ring" used something like "resistive element hob" to distinguish it from an inductive one.

[Tony Williams]

It's an inverter plus tuned tank coil generating a high frequency magnetic field that induces eddy current and hysteresis losses in the iron pot/pan, which then gets hot. Note the need for iron, not aluminium.

The advantage is that the heat is concentrated only in the iron pot/pan, the rest of the stove stays cool.

The disadvantages are the extra complexity of the inverter and the associated extra cost and probable unreliability.

[Andy Wade]

Thanks for that. I was familiar with the principle, but not the frequency of operation. Most web site descriptions seem to be at the "magic force field" level of explanation! Some sort-of imply mains frequency operation, but I could never quite see that working with such a large air gap in the magnetic circuit.

So by "high frequency" you mean what - the low kHz range, perhaps?

[easternangle]

Thanks to everyone who's posted replies. Although helpful on tother topics, nobody seems to have an answer to my primary question - what IS the life expectancy of these dratted things. 'Cos currently I'm thinking that spending a grand on 5 years' hob cooking is shockingly bad value for money however easy it is clean , and flexible it is to cook with!!!

[Tony Williams]

Yes. Only about 30KHz or so.

[Andy Wade]

Thanks.