Pan size matters more on the HIS8657U than on a gas range, and the reason is built into the cooktop. This 800 Series induction range is freestanding, 36 inches wide, with a 3.2 cu ft electric convection oven, and its zones come in several diameters and powers. A pan that performs brilliantly at front left can be sluggish at rear right.
An induction zone heats only the area of pan sitting over its coil. A large pan on a small zone warms slowly and unevenly, which is by design, and a pan that is too small may not trigger the zone at all. These cases account for many calls that turn out not to be repairs.
The glass also deserves care over such a large surface. Before suspecting a zone, we compare the pan with the zone and check the minimum pan diameter listed in the manual.
Look at diameters first. A zone heats only the part of the pan directly over its coil, so a big pan on a small zone warms slowly and unevenly, by design and not because of a defect.
If the pan covers enough of the coil, it is usually detected. If it is too small, the zone stays off. Each zone's minimum size is in the manual.
Try a known good pan that fits the zone's diameter, placed centered over the coil. If the same pan heats well on another zone and not on this one, the zone itself needs testing.
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