How do you remove the hotplate - Rangemaster Classic 110 (Dual Fuel) Dual Fuel (Electric and Gas) Kitchen Range

That hole is most likely a vent for oven where some heat escapes.

When this occurs the problem is always with the hotplate controllers. Has this happened to all hotplates at the same time or has it occurred over a certain time period?

I haven't heard of this problem before. If you do press down and the hotplate starts to work we know that the hotplates are okay. The only thing this could be is an internal problem inside the hotplate controller, possibly with the contacts. The controllers will need replacing.

If the rest of the hotplate elements are working correctly and you are performing the same tests with all of them then you have a problem. We know that the hotplate works. When hotplates are faulty they don't turn on and off, they just don't work. This would generally be a hotplate controller problem. It sounds as if the controller is faulty and requires replacing. If you are handy you can switch the suspect hotplate controller with a good one and see what happens. This will confirm our suspicions.

Remove that hotplate. Reset the breaker and see what happens,
Other hot plates do the same?

hi...first thing to do is canvas the price of the ceramic glass top,coz the price of the glass is half or more compare to the new one..do u think if u buy a glass only it is reasonable or waste ur money?then dont try to fix it by it ur self,coz the glass u buy is no warranty for wrong instalation.call an expert technician to do it to get an assurance for the warranty for installation.

Remove hotplate and oven control knobs. Under the 2nd and 5th knobs is an extra screw which holds on the front cover. Unscrew these and free the cover then access is gained to the screws (2 on each edge) which removes the plate to which the regulators are fixed.Remove the faulty regulator by unscrewing it from the plate,(2 screws) It is an easy job then to install the new part taking care to put the correct wires on the correct terminals. Reassemble, job done!

hi there.
not sure if this link will help you out but have a look.
how to remove hotplate on stoves 1100 esidla Google Search

Hotplate heating up when regulator/selector switched off. Hi ,this is gil1714 in Scotland. Two possibilities on this one, 1) the regulator is faulty:- replace
2) if the control circuit (regulator) is wired on the neutral side the hotplate may be leaking current to
earth, thereby completing the circuit. This would only occur on a supply that was not protected by
an RCD. If so replace hotplate. Hope this is useful,

Make sure your milk frother is not blocked.