I have had this washer/dryer for several years now and it has always been a bit of a mystery! Where does the fluff go? When I had a tumble dryer before, I was always clearing the fluff filter. There does not seem to be anything on this machine that deals with the fluff and I have recently found that the dryer is taking longer to dry things.
I am thinking of getting it serviced but can anyone give me an explanation as to what hapens so that I can save some money?
Some on the door seal, some down the drain with the water, and some into hoses.
In your case the fluff has probably built up in the condenser unit and hose at the back of the machine. This will have gradually built up over the years. A good service / clean out will do the job.