Induction Hobs

[puntloos]

Looking for the perfect induction hob. (aren't we all?). But in my particular case I have a couple of questions:
 

1/ My current (chef king) induction hob, when set to "low" reverts to a @Onoff @Onoff @Onoff pattern which is kinda annoying (sorry couldn't resist ), since especially when boiling pasta (in a pan with lid) it basically boils too much (pasta water/bubbles explode over the edge) and then it goes off the boil.. repeat.. A Bora rep tells me this is standard for induction. True? Anyone have a hob (bora or not) that is better at super low temp?

 

2/ Controls are important. I love my current hob's turning dial since I can turn down the hob in half a second without hitting the panic @Onoff button (okok I'll stop  ). My current ceramic hob on the other hand is TERRIBLE, its touch controls need a super annoying amount of persistence before they acknowledge what you want. 

 

3/ In-hob extractor quality vs standard. Again, Bora is a prime candidate. I'm suspecting it is something I want (as opposed to a hanging extractor, or a in-ceiling one, which also costs $$$) but Im not completely convinced it is good enough. Has anyone been able to contrast with in-ceiling, in particular how much grease settles on your surfaces?

 

4/ In-hob extractor cleaning. I'm not that messy a chef I think, but it's rare that my hob is sparkling clean after cooking.. which means the extractor probably ate some of what came down. How much cleaning do you have to do, and is the extractor (compared to a completely flat surface!) a massive extra hassle?

 

5/ Power. I love my hob's 3500W mode for starting a boil, but I rarely need anything beyond 'half power' for most cooking (although stir frying / wok style frying should theoretically be done at as much heat as your hob can muster. My recipe for Chinese style fried rice almost requires it...)

 

Would love to have thoughts/experiences. Thinking of Bora Pure currently..

 

Edited September 11, 2019 by puntloos

[Onoff]

I bought an Electra Elecheib induction hob from Comet as they were going bust in 2012. That well known make designed in Israel and made in Turkey!  ? Started at £399...reduced to £199 and then found a 15% off code. So £169.15 all in. Schott Ceran glass etc. Figured for the money we'd take a chance. Fanbloodytastic it's been too! Hasn't missed a beat. Pause button, power boost, excellent simmer function. Roll on Christmas dinner No.8. If anything I'd like slightly bigger rings but hey ho.

 

Tbh a pan with a lid tight on is basically a little pressure cooker irrespective of the heat source. As good as a simmer function is, if the pan isn't losing heat faster than it's coming into it, then boil over is inevitable. The auto switch off on the induction is a boon. Rarely happens tbh, just crack the lid a tad. The rep just didn't want to criticise your cooking technique! ?

[nod]

We have a five burner Neff and Italian extractor 

Hob took a bit of getting used to The magnetic circle thing 

But really impressed now 

The extractor was expensive

The lowest setting is fine

The highest is Like having a aircraft in the same room 

  

[vivienz]

I splashed out an outrageous amount of money on a Novy panorama.  Whether the price tag is justified is a very subjective question, but it was for me. Fabulous functionality on the hob. The controls are sliders but highly responsive and accurate. You can have a super-power option on one spot to bring pans of water to the boil quickly, you can set it to maintain 3 different temperature levels and the bridging function works well. The recirculating extractor is quiet and powerful; even searing steak on a hot skillet doesn't let grease vapour escape. Cleaning is a breeze; including the extractor, I can have the whole thing wiped down and cleaned in about 2 minutes. A squirt of kitchen spray, wipe with  wet cloth then wipe with a microfibre glass cloth.

 

I'm not a fan of the bora - I did try one out in a kitchen studio but the novy is in a separate class (with a price tag to match, it must be said).

[MikeSharp01]

Looks good too, are the units handless?

 

[Jeremy Harris]

9 hours ago, puntloos said:

 

1/ My current (chef king) induction hob, when set to "low" reverts to a @Onoff @Onoff @Onoff pattern which is kinda annoying (sorry couldn't resist ), since especially when boiling pasta (in a pan with lid) it basically boils too much (pasta water/bubbles explode over the edge) and then it goes off the boil.. repeat.. A Bora rep tells me this is standard for induction. True? Anyone have a hob (bora or not) that is better at super low temp?

 

 

All induction hobs use pulse width modulation to control the heat output, so all will pulse on and off.  However, it does seem that some do this with a finer degree of control than others, also the heat capacity of the pan that's being used makes a significant difference.  Since we switched to using Le Creuset pans we've found that the heat is a fair bit more controllable, and it's now very easy to just simmer.

[MrMagic]

We've got an Electrolux induction hob - absolutely love it. We don't seem to get any of the on/off that you're talking about.... simmers perfectly (it's obviously pulsing somehow but there no noticable changes to the pan/boiling/simmering etc)... it maintains a consistent temperature.

 

For us the key decision points were - 

Size - wanted a wide hob

Controls - we wanted individual controls for each 'ring', quite a lot of them seem to have a single control and a selector to choose the 'ring' which when something is boiling over is a PITA

Power - Ours can do all the power boiling etc, think it's rated at about 7Kw all in

 

Sadly, no longer made - https://www.appliancesdirect.co.uk/p/ehl8740fok/electrolux-ehl8740fok-0-induction-hob-hob

 

Controls when turned on...

 

[ragg987]

Second vote for Neff with magnetic disc control. Cannot notice any pulsing, when I want controlled low heat I simply dial in the number and it works without fail (porridge is no 3, Moka pot is no 4.5).

 

Super easy to operate with rotary knob, cleaning surface is flat after knob removed, has power boost mode and flexible zones.

 

Came from gas and also have used ceramic hob. I only miss gas when cooking in a wok.

[puntloos]

The interesting part of in-hob extraction is of course you don't have to buy a hood but I'm indeed worried about the downsides.

 

Guess I have to stop at a hob shop at some point. Does anyone know a London(or Herts.) area store that actually has hobs where you can ideally trial-cook on them or at least see them in action, and at a reasonable price?

 

Perhaps also the separate extractors (gaggenau?) might be helpful alternatives to get the best-of-all-worlds.

 

Indeed I think induction does have some minimum power that works at all, so going below that requires a pulsing approach, but indeeed my current hob turns on for 2 seconds, off for 3 at the lowest.. 

 

Pasta/Cooking skillz> ahh.. caught! (to be honest I just wanted to save a little energy)

[puntloos]

5 hours ago, vivienz said:

I splashed out an outrageous amount of money on a Novy panorama.  Whether the price tag is justified is a very subjective question, but it was for me.

 

Define 'outrageous'? - Since UK companies are legally allowed to be coy with prices, I see the 1831 in germany for GBP 2669 - (the 1821 is a 3295). if that means you don't need a hood it might not be a terrible deal.

Still, obv a lot of money compared to the Bora Pure, which is  is in the 1600 area, I understand.

 

Did you consider any other alternatives?

 

5 hours ago, vivienz said:

Fabulous functionality on the hob. The controls are sliders but highly responsive and accurate. You can have a super-power option on one spot to bring pans of water to the boil quickly, you can set it to maintain 3 different temperature levels and the bridging function works well.

ah so you have the 1821 then, I wondered how that temperature setting thing works, since pans are different (and therefore respond differently to inductionizing them..

5 hours ago, vivienz said:

 

The recirculating extractor is quiet and powerful; even searing steak on a hot skillet doesn't let grease vapour escape.

 

My concern is that the pans I'm most actively using are close to me, while the extractor is at the far end of the hob. How do you compromise? Or does extraction still work okay for even the farthest pans? I'm tempted to choose the 'centrally located' extractors for this reason, eg the Novy One 1801?
 

5 hours ago, vivienz said:

Cleaning is a breeze; including the extractor, I can have the whole thing wiped down and cleaned in about 2 minutes. A squirt of kitchen spray, wipe with  wet cloth then wipe with a microfibre glass cloth.

 

Do you need a full wipedown every day you cook? 2mins is okay, but I clean my hob in 30 seconds  

 

5 hours ago, vivienz said:

I'm not a fan of the bora - I did try one out in a kitchen studio but the novy is in a separate class (with a price tag to match, it must be said).

 

 

The Novy does have the advantage that my concern of stuff splashing into it is a bit lessened.

[vivienz]

I'm also going to be coy on price, just in case OH should stumble across this thread, but the German price will need all extraction kit and accessories added on, in true German car purchasing style.

 

I came within an ace of buying a Gutmann and looked at Bora but was seduced by the Novy.

 

Cleaning- just the hob is a 30 second effort but novelty value is still present having had gas hobs all my life. I will get bored with cleaning very soon. Guaranteed.

 

Distance of pans from the extractor - the zones are in a line parallel to the extractor and so are equidistant. The extractor has 3 height settings and I opt for whichever one matches the highest pan.

[puntloos]

3 minutes ago, vivienz said:

I'm also going to be coy on price, just in case OH should stumble across this thread, but the German price will need all extraction kit and accessories added on, in true German car purchasing style.

 

Who is OH? - are there any rules against mentioning prices?

 

3 minutes ago, vivienz said:

 

I came within an ace of buying a Gutmann and looked at Bora but was seduced by the Novy.

 

Cleaning- just the hob is a 30 second effort but novelty value is still present having had gas hobs all my life. I will get bored with cleaning very soon. Guaranteed.

 

Distance of pans from the extractor - the zones are in a line parallel to the extractor and so are equidistant. The extractor has 3 height settings and I opt for whichever one matches the highest pan.

Not sure I understand, here's my artist impression:

 

 

Clearly (...) if you want the pan to be close to you, it will have to be far away from the extractor, no?

 

 

[Ferdinand]

OH = Other Half.

 

She means hubby is a broke man walking who does not know it yet .

 

Or alternatively thinks he is broke for the wrong reason ; she may have mentioned something of benefit to OH in passing but carefully avoid stating a definite link so he will just assume it was him.

 

The only rule against mentioning prices is case specific and to do with household harmony.

 

Mention away. 

 

That bottom piccie ... are you a friend of Jeremy Clarkson?

Edited September 12, 2019 by Ferdinand

[puntloos]

 

7 minutes ago, Ferdinand said:

OH = Other Half.

 

She means hubby is a broke man walking who does not know it yet .

 

Or alternatively thinks he is broke for the wrong reason .

 

The only rule against mentioning prices is case specific and to do with household harmony.

 

Mention away. 

 

Oh good, I'm member of a facebook group where it's taboo to mention prices. Haven't given it too deeply a thought, of course it's not in the salesmen's interest, but some buyers also tend to focus a little too much on the last $.. 

 

Quote

 

That bottom piccie ... are you a friend of Jeremy Clarkson?

 

 that's me, in 10 years, if the hobs are this amazing I won't do anything else..

 

But yeah, interesting to hear a real(ish) quote for the entire kit.

 

Since I'm starting from scratch I assume(?) it makes sense to duct the air into the MVHR rather than recirculating

Edited September 12, 2019 by puntloos

[Ferdinand]

1 hour ago, puntloos said:

 

 

Oh good, I'm member of a facebook group where it's taboo to mention prices. Haven't given it too deeply a thought, of course it's not in the salesmen's interest, but some buyers also tend to focus a little too much on the last $.. 

 

 

 that's me, in 10 years, if the hobs are this amazing I won't do anything else..

 

But yeah, interesting to hear a real(ish) quote for the entire kit.

 

Since I'm starting from scratch I assume(?) it makes sense to duct the air into the MVHR rather than recirculating

 

There are actually all kinds of pricing comparison threads - but you have to dig, sometimes using Google and +buildhub or site:buildhub.org.

 

F

[Ferdinand]

On 12/09/2019 at 00:13, puntloos said:

4/ In-hob extractor cleaning. I'm not that messy a chef I think, but it's rare that my hob is sparkling clean after cooking.. which means the extractor probably ate some of what came down. How much cleaning do you have to do, and is the extractor (compared to a completely flat surface!) a massive extra hassle?

 

 

My golden rule for extractor filters is that it shall *always* be a metal one that can go in the dishwasher.

 

19 hours ago, puntloos said:

Since I'm starting from scratch I assume(?) it makes sense to duct the air into the MVHR rather than recirculating

[Jeremy Harris]

19 hours ago, puntloos said:

 

 

Since I'm starting from scratch I assume(?) it makes sense to duct the air into the MVHR rather than recirculating

 

Not a good idea to do this, IMHO.

 

A hob extractor moves many times the amount of air that an MVHR system moves, so the system will become massively imbalanced if it gets many tens of litres per second of additional flow pumped into the extract side.  Also, no matter how good the filters are on the hob extract there will always be residual fat vapour etc in the extracted air, which will end up coating the MVHR ducting and clogging the filter (MVHR filters aren't designed to deal with "dirty" air like this).

 

Best bet is a recirculating hob extract, with a good filtration system.  That ensures that the MVHR remains balanced and that the MVHR ducts etc are less likely to get affected by cooking residues.   You can opt to just have a normal extract vent, but this may pose an airtightness problem when it's not in use, and the MVHR will end up unbalanced when the extract is in use.

 

FWIW, I fitted provision in our kitchen for a recirculating overhead hood, but we've found that we just don't need one.  The MVHR does a good job of clearing away steam and cooking smells, and as we never fry anything we don't have a potential problem with airborne fat etc.  One thing I did add, which seems to work well, is a fresh air supply duct from the MVHR in the ceiling just outside the kitchen door.  This seems to work well to stop cooking smells escaping from the kitchen, as there's always fresh air available by the door, that flows across the kitchen towards the MVHR extract in the corner.

 

[puntloos]

4 hours ago, JSHarris said:

 

Not a good idea to do this, IMHO.

 

A hob extractor moves many times the amount of air that an MVHR system moves, so the system will become massively imbalanced if it gets many tens of litres per second of additional flow pumped into the extract side.  Also, no matter how good the filters are on the hob extract there will always be residual fat vapour etc in the extracted air, which will end up coating the MVHR ducting and clogging the filter (MVHR filters aren't designed to deal with "dirty" air like this).

Interesting, while you guys have already edjumacated me a bit on what MVHR really is I still had in my head that it could have both "powerful" as well as "low flow" modes, pipes etc.

(I guess as an ex electrical engineer I sortof mentally model air like I would electricity, but I should stop that)

 

Obviously it would be amazing if there is an all-singing-all-dancing air system that would heat cool, dry, moisturize, storm and breeze air but I am guessing I might need multiple systems.

 

4 hours ago, JSHarris said:

 

Best bet is a recirculating hob extract, with a good filtration system.  That ensures that the MVHR remains balanced and that the MVHR ducts etc are less likely to get affected by cooking residues.  

Indeed, this was a worry I had.

 

4 hours ago, JSHarris said:

You can opt to just have a normal extract vent, but this may pose an airtightness problem when it's not in use, and the MVHR will end up unbalanced when the extract is in use.

 

I'd need to read up more on the 'balance' thing, are you worried the extracted hot/greasy air will make things worse than if the air(+heat) stays in the area?

 

4 hours ago, JSHarris said:

FWIW, I fitted provision in our kitchen for a recirculating overhead hood, but we've found that we just don't need one.  The MVHR does a good job of clearing away steam and cooking smells, and as we never fry anything

Ah, you're irish? (non-obvious Denis Leary Reference.. )

 

4 hours ago, JSHarris said:

we don't have a potential problem with airborne fat etc.  One thing I did add, which seems to work well, is a fresh air supply duct from the MVHR in the ceiling just outside the kitchen door.  This seems to work well to stop cooking smells escaping from the kitchen, as there's always fresh air available by the door, that flows across the kitchen towards the MVHR extract in the corner.

 

I guess one mismatch in thinking I have is that to me 'cooking' requires 'high power everything' (ventilation, heat) yet MVHR sounds underequipped to duct fresh air in or out?

[Conor]

I had this conversation with my neighbour that designs and installs MVHR systems. Yes, you need a high flow kitchen extractor to keep the dirty air away from the MVHR system as it'll ruin the filters. And yes, when an extractor is on, it'll ruin the performance of the MVHR, but it really doesn't matter as it's normally for short term use only. And regards airtightness, you can get weighted dampers that will only open when the extractor is on and are passive certified.

 

I'm going for a 500m³/hr externally mounted extractor fan. Will be ducted with 160mm ducting to ceiling mounted flat filters above the island. There's no bloody way a downdraft extractor would cope with my cooking. Flames are the norm.

[Jeremy Harris]

To give an idea of the mismatch, a kitchen MVHR terminal is required to extract at 13l/s.  A typical hob extract will run at anything between 50l/s and 150l/s.

 

The balance problem has to do with the way MVHR fundamentally works.  There are two fans in an MVHR, one drawing air in from outside, pushing it through the heat exchanger and then out to the fresh air supply ducts.  The other fan draws air from the house extract ducts and pushes it through the other side of the heat exchanger, where it gives up some heat to the incoming fresh air, before being expelled via the external exhaust.  To work efficiently, these two air flows need to be matched, so the flow rate coming in matches the flow rate being exhausted.  If an extractor in the kitchen pulls air from that room and blows it outside, it will reduce the pressure in the house and upset the balance of the air flowing through the heat exchanger.  The incoming air flow will increase, and over power the ability of the heat exchanger to work efficiently.

[Jeremy Harris]

4 minutes ago, Conor said:

I had this conversation with my neighbour that designs and installs MVHR systems. Yes, you need a high flow kitchen extractor to keep the dirty air away from the MVHR system as it'll ruin the filters. And yes, when an extractor is on, it'll ruin the performance of the MVHR, but it really doesn't matter as it's normally for short term use only. And regards airtightness, you can get weighted dampers that will only open when the extractor is on and are passive certified.

 

I'm going for a 500m³/hr externally mounted extractor fan. Will be ducted with 160mm ducting to ceiling mounted flat filters above the island. There's no bloody way a downdraft extractor would cope with my cooking. Flames are the norm.

 

 

How are you sealing up the extractor duct/terminal to both prevent cold air being drawn in when it's not running, and to prevent thermal bridging when it's not in use?

 

We've had debates about this before, and the challenge has always been finding a solution to this problem.  Something like a double valve system is needed, with completely airtight valves (at least as good as the door/windows seals).

[Conor]

@JSHarris Something like this or an actuated damper that opens and closes as extractor is activated 

 

https://munsterhrv.ie/shop?olsPage=products%2F150mm-thermobox-airtight-cooker-hood-damper

 

The fan i plan on using also has a built in damper. This would be on the external side of the wall, and the other damper within the inner ICF layer - creating a sealed tunnel of air approx 200mm long through the concrete core and to the outer EPS layer.

Edited September 13, 2019 by Conor

[Jeremy Harris]

Just now, Conor said:

@JSHarris Something like this or an actuated damper that opens and closes as extractor is activated 

 

https://munsterhrv.ie/shop?olsPage=products%2F150mm-thermobox-airtight-cooker-hood-damper

 

The fan i plan on using also has a built in damper. This would be on the external side of the wall, and the other damper within the inner ICF layer - creating a sealed tunnel of air approx 200mm long through the concrete core and to the outer EPS layer.

 

 

Two of those in line would help, for sure, but it really needs something to insulate the thermal bridge created by the big duct when not in use (which will be most of  the time).  I think that last time we debated this (may have been in a passive cat flap thread) the idea of having a removable plug of insulation that filled the gap was mooted.

 

The other problem is that, in order to get the extract to work at around 100 to 150l/s, another intake duct is going to be needed, otherwise there won't be a route to get enough air in to replace that being extracted.  This means another 150mm hole to let air in, bypassing the MVHR (which will be massively to restrictive to let this much air in).

[puntloos]

4 hours ago, JSHarris said:

 

 

Two of those in line would help, for sure, but it really needs something to insulate the thermal bridge created by the big duct

 

 

Could you elaborate a little on this one? Simplifying: imagine a "perfectly" insulated house, then punching a duct-size hole in it, with two of the above in line.. 

 

Are you suggesting the two dampers don't insulate well, or are you saying the duct touching the outside wall, then going inside, and touching the inside wall is a sufficiently "serious" thermal bridge to worry about?

 

I suspect the latter, but surely (?) there are ducts that can be made of insulating material? No technology that allows a decent external duct?

 

 

[Jeremy Harris]

7 hours ago, puntloos said:

 

Could you elaborate a little on this one? Simplifying: imagine a "perfectly" insulated house, then punching a duct-size hole in it, with two of the above in line.. 

 

Are you suggesting the two dampers don't insulate well, or are you saying the duct touching the outside wall, then going inside, and touching the inside wall is a sufficiently "serious" thermal bridge to worry about?

 

I suspect the latter, but surely (?) there are ducts that can be made of insulating material? No technology that allows a decent external duct?

 

 

 

 

The dampers provide near-zero insulation, they just stop air flowing through the duct.  The duct will therefore act as a thermal bridge, as it's effectively a hole in the insulation layer.  Without filling that hole with something to provide insulation, it will always be a thermal bridge.