Pressure cooker and induction hob

[ericmark]

With a new induction hob we realised the old pressure cooker would not work. Looking we see there are pressure cookers designed to work with induction hobs however I was a little concerned as to the safety aspects of a pressure cooker with such a powerful hob. (3.7Kw on boost) Although one would not normally use full 3.7kW I wanted to ensure the pressure cooker would be safe if phone or door bell was to call one away from the kitchen.

So I wrote to manufacture and got following replys:-

"Dear Mr xxxxxx

May we advise that all our current stainless steel models (Smartplus 6L and Quick and Easy 3L) are suitable for induction hobs. There is no recommended maximum power settings for domestic induction hobs, but as with any type of hob, once pressure is reached, the power should be reduced to the minimum setting to maintain pressure.

However, as you are stating a 3.7kW hob, which is more powerful than our research on domestic hobs suggests, can we ask is it a commercial hob? If so, we are unable to comment further as we have no experience of using pressure cookers on such hobs as they are for domestic use only.

Kind Regards, Amy Jones
Customer Service Representative

Thank you for your further email.

May we advise that as we are only cookware/pressure cooker specialists, it may be worth asking your hob manufacture for the more detailed information. However, as long as once the pressure is reached, the heat source is lowered to a simmer to maintain pressure then it will be suitable.

Basically, as long as the pressure cooker is not kept on a high heat the whole time it will be fine.

Kind Regards, Amy Jones
Customer Service Representative"

Not sure how the cooker manufacturer would know how much power a pressure cooker can safely handle as they only make the cooker they don't make the pan. However rather worried that a manufacturer does not know what the safe power is for the pans they make. I could not see any other boiler manufacturer getting away with not providing information on their products. Safety first so we are not using a pressure cooker.

However would like to know.
1) Does anyone use a pressure cooker with an induction hob.
2) Any accidents any one knows of.
3) Thoughts on building boilers with no test info.

PS I did tell them it was a Belling FSE60i cooker which is a domestic type.

 

[Chri5]

We use our pressure cooker frequently, on a gas hob.

No matter what the energy source the common denominator is that once the pressure is reached, and the indicator for pressure right- there is absolutely no point in maintaining "up to pressure" energy use.

Our's will simply push more steam / vapour out the overflow valve. Thus the contents at high energy would simply dry out quicker- it certainly won't cook any quicker.

So at the end of my ramble, what is the point in asking for details as to if a pressure cooker on a induction hob can maintain maximum energy settings for a long, long period.

That's not how you'd use one on normal gas or electric plates, so why would you want to on a induction hob ?

 

[ericmark]

I did say

Although one would not normally use full 3.7kW I wanted to ensure the pressure cooker would be safe if phone or door bell was to call one away from the kitchen.

I would be first to agree normally one would turn it down but two points.
1) What happens if one is distracted?
2) What happens if one relies on the auto system and it is late turning down power.

Never used gas at home they are not safe they all have a naked flame and many only have fingers to hold pan no flat service to ensure steady pan. Plus they do not auto turn off if left. Or have auto boil then simmer ability. And of course they don't use renewable power.

The only reason to use gas is where electric supply is not good enough like in a caravan or to use a wok.

Having a safe electric cooker which auto turns off when you remove a pan. So also saves energy as well. We also want other items to also be safe.

I am questioning what happens if the pressure cooker is left. What one hopes will happen is water will boil away. The pan temperature will rise and it will trigger the cookers over temperature sensor and shut down safe. But it seems they can't guarantee that would be the scenario. Which is not really acceptable as the alternative is for the unit to explode.

 

[MrTinker]

Pressure cookers have two pressure relief valves, one being used to maintain a fairly constant pressure whilst cooking, the other is a safety valve, which remains closed in normal use, and is set to open above normal operating pressure, but below dangerous levels. The safety valves are designed to, a; have a high flow rate(much higher than the control valve), b; once it has operated it will not reseal itself when the pressure drops, thus keeping the pan vented, so it will just boil dry like an open pan, and not explode!

 

[electronicsuk]

I don't see why it would be unsafe if used as intended. If you leave the kitchen to answer the door while leaving the hob on full pelt with a pressure cooker on top, then that's your own fault. After all, would you do the same thing with a chip pan?

 

[Stoday]

Power's not much different from a gas ring. High speed burner = 3kW; wok burner = 3.6kW.

 

[ban-all-sheds]

My new cooker has a 5kW wok burner.....

I would be first to agree normally one would turn it down but two points.
1) What happens if one is distracted?

That can happen with any heat source.

2) What happens if one relies on the auto system and it is late turning down power.

What happens if one relies on any automatic control which goes wrong, e.g. immersion heater stat and the cylinder gets to boiling point?

Never used gas at home

Then you're probably not qualified to comment.

The only reason to use gas is where electric supply is not good enough like in a caravan or to use a wok.

Wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong.

Having a safe electric cooker which auto turns off when you remove a pan.

A very bad habit to get into, particularly if you ever transfer it to an old-fashioned solid-hotplate electric hob.

I am questioning what happens if the pressure cooker is left.

The same as with any other heat source.

What one hopes will happen is water will boil away. The pan temperature will rise and it will trigger the cookers over temperature sensor and shut down safe. But it seems they can't guarantee that would be the scenario. Which is not really acceptable as the alternative is for the unit to explode.

Why would it explode?

Seems to me your concerns are all based on superstitious fears of pressure cookers per se, and the heat source is utterly irrelevant.

 

[viewer]

Hi, more a question than an answer - all the induction hobs I've used have dual controls i.e. they can be set for a level (say 1 to 10) or for a temperature. They seem to be pretty good at keeping the temperature as set, although the one we use at the moment has settings at 20C intervals - so you'd need to choose 100 or 120 for a pressure cooker. I always thought (stand to be corrected) that the magnetic field was produced only as needed; so you only set the final temperature (a higher setting would not speed up the process as it would with say, gas. What does this hob use to output control levels that is so different?
BTW - proper pressure cookers for induction great (some people have put an iron disc inside an aluminium one) so SWMBO may get one - I kept telling her they didn't exist!

 

[ericmark]

My new cooker has a 5kW wok burner.....

But how much of that 5kW goes into the food. My daughter uses gas with 5kW burner yet electric kettle boils water quicker at just 3kW. Clearly since with my 3kW hob it takes same time as the kettle 2kW at least is wasted.

Never used gas at home

Then you're probably not qualified to comment.

Did use gas in Hong Kong, in the caravan, in the boat, and for central heating. But just not safe for use with a hob when an alternative like electric is available. As a kid all solid fuel no naked flame except when filling but still don't like the dust they make. The big problem with solid fuel and gas is the heat also goes into the kitchen. And also with gas it puts loads of water into the kitchen. So one has to have large extractors to remove the heat and water which are not required with electric.

The only reason to use gas is where electric supply is not good enough like in a caravan or to use a wok.

Wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong wrong.

So should I just say Right Right Right? Look at the caravan and boat fires and just see how many were either caused by gas cooking or made worse because of gas cooking. For my gas fire the fitter tests the flue to ensure the dangerous fumes don't enter the room and go up the flue. Unless you build a glove box around the gas cooker no way can you be sure all fumes go up the extractor and to date never seen an interlock so you can't switch on cooker without the extractor running first.

I am questioning what happens if the pressure cooker is left.

The same as with any other heat source.

Not really. If the heat source is less than the amount that the pan can handle then all is safe and only problem is pan will boil dry. If the heat source is greater than pan can handle then a big bang.

What one hopes will happen is water will boil away. The pan temperature will rise and it will trigger the cookers over temperature sensor and shut down safe. But it seems they can't guarantee that would be the scenario. Which is not really acceptable as the alternative is for the unit to explode.

Why would it explode?

Seems to me your concerns are all based on superstitious fears of pressure cookers per se, and the heat source is utterly irrelevant.

If the steam can't release from the pan fast enough then something must give. The old pressure cookers had a plug that would fire out of the pressure cooker like a bullet there was a mark on my mothers celling for many years where this happened when using solid fuel cooking and she did not move the pan to cooler region in time. Some new ones don't have this bung so would really go bang.

If there is a safety device that will release the pressure safely one would have expected the manufacturer to have stated this in their letter to me. It seems many pressure cookers state in the instructions not to be used with gas hobs. One would guess this is because the gas hob has a higher output than the old electric. The fact that the cooker manufacturer did not know that cookers can produce 3.7kW into the food and thought it was some commercial cooker clearly shows they have not kept pace with modern cookers. So until the manufacturer says it safe then no pressure cooker for me.

Maybe they will produce one with built in heater like the electric kettle? Then there would be no problem.

 

[ericmark]

Hi, more a question than an answer - all the induction hobs I've used have dual controls i.e. they can be set for a level (say 1 to 10) or for a temperature. They seem to be pretty good at keeping the temperature as set, although the one we use at the moment has settings at 20C intervals - so you'd need to choose 100 or 120 for a pressure cooker. I always thought (stand to be corrected) that the magnetic field was produced only as needed; so you only set the final temperature (a higher setting would not speed up the process as it would with say, gas. What does this hob use to output control levels that is so different?
BTW - proper pressure cookers for induction great (some people have put an iron disc inside an aluminium one) so SWMBO may get one - I kept telling her they didn't exist!

I would agree that the control of the induction hob is now fast and has loads of safeguards but mine is only power output not temperature the latter likely would not work with many pressure cookers. The temperature is measured and it will auto switch at 200 degs and that's the glass temperature not the pan which could be hotter and at 200 degs water will produce a pressure of 14.7 lbs/sq inch i.e. double the pressure and one doubles the temperature at which water will boil.

At 250 degrees it reduces power to 60% which is less than a old type cooker could produce so at that point it would be safe but looking at 22 lbs/sq inch and if any bung pops at this pressure it would really go with a bang and also of course fill kitchen with steam so may be a problem finding the switch to turn off.

Being honest since the boost has a time limit when the boost function is used and likely this will be exceeded before anything bad happens. And one does not have to use the boost feature and likely one would use the auto boil at level 5 which means full power 2.3kW for 7 minutes at which point it will auto turn down to level 5. With a cold pan it is unlikely the water will have reached the temperature required to blow off steam and it will revert to simmer far too early.

However what I asked was if mistakes are made for example turning on boost instead of auto boil and walk out of room thinking all is safe would the pan safely cope with the error.

It seems the pan manufacturer can't answer the question. Which makes one ask why. One would have expected that any manufacturer of a pressure vessel would have had to test it to show it was safe.

We do not say you can use knife switches as to get a shock you would need to put your hand on the live parts of the switch and you would be daft to do that. No we say accidents do happen so don't use knife switches all live parts must be where we can't touch them.

And although I would agree with care and consideration the pressure cooker is safe. Accidents do happen and maybe one day some one will turn the knob clockwise and hold instead of anticlockwise and hold and set the hob to boost instead of auto boil and then answer the door thinking everything set to auto.

With digital controls the same applies setting to P instead of A may burn the food and even kill the pan although most pans can take 200 degrees C. But a little different with a pressure cooker and don't really want even the rubber safety bung flying around the kitchen or the lead bung melting and blowing around.

Maybe they are safe. But if safe surely the manufacturer would have said so. Rather than trying to put the question on the hob manufacturer.

 

[viewer]

Hi, Thanks for answer. The position does sound odd; you would think that surely the pot makers would make their equipment for hobs and the hob makers for the pots with some sort of common standard (obviously not!).
It also sounds a bit odd that a hob would not be made with some sort of lower temperature settings as boiling, simmering etc must be a normal requirement. Ah well, back to the Rayburn.

 

[IJWS15]

Can the OP explain why he has the yutmost faith in the safety devices/systems (many electronic) in his hob but no faith at all in the safety devise in the pressure cooker?

I for one would have more faith in the pressure relief valve on the pressure cooker than the hob's electronics. Do you know if they fail safe or allow wrong side failures?

When did you last see in the news that a pressure cooker had exploded . . .

And gas is far better for a hob than any of these new fangled electric things. . . . .

 

[ban-all-sheds]

Eric - so, to summarise.

You think gas is scary and dangerous, and should be avoided if at all possible.

You think pressure cookers are scary and dangerous and should be avoided unless the maker tells you they'll be OK.

I give up.