Hi
The heater you refer to DOES NOT evaporate the water.
It is the heat from the motor the does this.
I would be of the opinion that the small pipe that drains the water onto the tray around the motor has blocked.
A pipe cleaner or something similar pushed down the pipe from inside the fridge section should cure your problem.
If you can not locate the drain from inside the fridge please go to the back of the fridge and look for a plastic tray either around, on or below the motor.
There you will see a small plastic pipe.
Remove dirt from said pipe.
Good luck.
Harry
July 2014