What is an induction hob and how does it work?
Not to be confused with an electric hob, induction hobs have a series of copper coils under each cooking zone, an alternating electrical current is passed through the coil which creates an oscillating magnetic field that induces an electrical current in the pot – In simple terms, the contents of the pan are heated by an electro-magnetic current and not by the surface of the cooktop.
To use an induction hob, you will need to have compatible, conductive pots and pans. The best pans to use are those with a flat, even thick base made of ferrous metal (cast iron or steel). To check if a pan will work, run a magnet across the base, if the magnet sticks, the pan will work.
Look at the images below, the base shown on the left is perfect for induction, smooth, flat and even. The base on the right will work although nowhere near as efficiently, the magnetic base is thin and full of holes.
Not all induction hobs are the same. Size, zoning, function and control type vary across all makes and models. Here we have put together an overview of the options available to you.
Induction hobs are widely available in the following standard widths – 30, 60, 70, 80 and 90cm
Panoramic hobs (below) which are 90cm wide are available from some manufacturers, these are ideal for shallow depth worktops and islands with breakfast bar behind.
These are very straight forward to use, a simple induction hob with independently controlled cooking zones marked by a ring or cross to show the centre of the coil below.
Flex / Dual Zone Induction hobs
An induction hob with one or more large cooking areas that can be selected to work independently or split into 2 or more zones. These types of hob are great for a host of reasons, you can use hot plates or griddles with ease and have full temperature control over the complete cooking surface, multiple pots can be placed anywhere on the flex zone too.
With some models, the flex-zone can be pre-programmed to have set power levels at the front, middle and rear which is particularly useful if you are cooking foods that need to be brought to the boil, simmered and kept warm intermittently, all without having to amend the controls.
Free Induction hobs
The “Rolls Royce” of induction cooking, these premium hobs offer complete freedom and flexibility for control and pan placement. Lots of small copper coils are tightly grouped together below the cooktop, the magnet below each will detect your cookware wherever it is placed and the corresponding coils are activated to suit the pan shape and size.
Free induction hobs are controlled by a full TFT screen which will display the position of your cookware, tap on the desired pan and open up a control menu to alter the power setting and timer. Premium hobs come with a premium price, expect to pay between £1,800 and £3,000 for a hob of this type.
There are 4 different types of control / interface for induction hobs.
This control type will be found on basic entry level hobs. Simply touch the marker that represents the ring you wish to operate, tap the + or – buttons to adjust the temperature. Hold the + for 3 seconds to jump straight to full power and hold – for 3 seconds to jump straight to zero.
This control type can be found on most types of hob, apart from free-induction. Simply touch the marker that represents the ring you wish to operate, then either tap the required power level on the corresponding ‘power bar’ or slide your finger along it to set the desired level.
This control type can only be found on certain brands. Much like slide control, you touch the marker / indicator that represents the ring you wish to operate then twist the dial to quickly adjust the power level. These dials are usually magnetic and can be easily removed to make cleaning the hob easier.
Full TFT (touch screen) Control
This control type is reserved for high end, premium hobs. Like a smart phone, the full colour display is touch controlled and has a comprehensive operating menu. Once your cookware is placed on the hob, it will be displayed on the screen showing it’s position. Tap on the screen to highlight the desired pan and use the touch screen to adjust the power setting, timer or physical temperature required. Some models may have pre-programmed settings for certain recipes or food types, making cooking effortless. Some brands have clever accessories like pan sensors that stick to the sides of your cookware, these sensors communicate with the hob via Bluetooth to regulate the temperature precisely.