Hi, i have had the same problem as you guys, the filter lamp just lights up all the time. I have tried to clean the first filter and the "second" filter( the filter box you can gain access to by opening the lid situated just above the water container). That did not help, but i was sure that i was on to something. My thought was that there is some kind of sensor, that picks up how much humidity there is left in the clothing. This seems logical, and i guess this true. But i just couldnt seem to find out where the clog was. Then i discovered that if you take out the "second" filter (the filterbox mentioned earlier), there is a compartment underneath this filter. The compartment seems to be a kind of buffer for the watercontainer( By the way, pull out the water container to get a better look of where this containment is). In this compartment there was loads of sticky fluff, this fluff clogged the valve to the water container. So i used a cloth to clean out all the water, and made sure i got all the fluff out of there. I also used a q-tip to clean the exit point of the valve(the end that goes inn to the water container).
That seemed to do the trick ! Im guessing that there is some kind of sensor in that compartment, and when the water container is full, the compartment (buffer) fills up and triggers a sensor:)
Let me know if it resolved your problems. That way we can find out if this is a problem that occurs often.
Thomas Bjerkeli, May 2011