immersion heater sizes

[timegoesby]

Are immersion heaters available that have a higher output than the standard 3 kWatts, that fit into a standard immersion port in a cylinder?

thanks

[BigWallop]

In the UK, the 3kW elements are the norm' but you can get a retro-fit flange to take a second shorter element in through the side of the cylinder. If you do increase the Wattage you'll also have to increase the cable size that supplies it, so watch out, as it's not just a case of fitting a higher rated heater.