Candy Alise fluff build up

Thanks John. There hasn't been any air extraction pipes (or venting hose) for washer dryers since about the early 1980s when Hoover made one. All washer dryers are condenser washer dryers. The hot steam hits a trickle of cold water in a condenser chamber at the back (which is why the washing machine still needs water supply during drying cycle). The stealing condensers back into water runs into the bottom of the drum and is pumped out as normal. Likewise the fluff is supposed to be washed down with this water and is easily pumped away.

It seems that many people have a lot of trouble with washer dryers clogging up or getting a buildup of fluff or even grit etc. My personal suspicion is that many of them may well be being overloaded. If you overload a washer dryer I believe it creates an extremely damp environment that the appliance cannot properly deal with. This causes the fluff and linked to stick inside the heating element chamber and fan chamber and just keep building up until it causes problems. I cannot rule out the possibility that some are caused by just poor design or faults but you definitely need to pay a lot of attention to the instruction manual about how many items of laundry can be dried in the dryer cycle. This is typically less, and sometimes much less, than the amount of laundry that the washing machine has just washed.

In the early days of washer dryers they could only tumble dry half the amount that they washed. Things have improved, but most washer dryers are likely to need some laundry removing before going onto the drying cycle if it is a full load that has been washed. I suspect many people just try to wash and dry the same load, which unless it is a particularly light load is a bad idea.

To wash laundry you need items packed together and constantly rubbing against each other. But to dry laundry you need a lot of space for the laundry to drop through hot air as the drum revolves. If you think about it a tumble dryer has a drum that is typically at least twice as big as a washing machine drum. So these are two totally separate requirements and not really conducive to having one appliance carrying them out. However, washer dryers have been popular for many many years since they came out in the 80s. They are a compromise machine, with the sole advantage of being cheaper and taking up less space. Apart from that everything else is a disadvantage when compared to separate appliances.

You might be interested in reading both of my articles here where I describe all of the pros and cons of washer dryers

Pros & Cons of washer dryer v separate washing machine | https://www.whitegoodshelp.co.uk/washer-dryer-or-separate-washing-machine-and-dryer-which-is-the-best/