The trouble with the wording is that it might also refer to kettles, some types of air-conditioners / heaters, instant boilers, steamers, any other device which heats up water (especially those which have the sole purpose of producing warm/hot water). So according to "law" you're not allowed to plug your kettle into the same circuit your food processor uses - it needs a "dedicated" circuit (think similar to the "clean-power" circuits used in some offices for PC's).

Obviously this is over the top and not adhered to in practice - probably it wasn't even the intention of the original law. Though because of the wording it becomes a blurred area. I wonder if it has some form of clarification to specifically state what it means by "water heater" or what "water heaters" are excluded from this provision.