Dryer problem
I've just had a the same problem with this model, locking out with error code E20 ...but fixed it!, and i tell you what - it's not difficult. Give it a go and save yourself loads of money in the cost of professional service, repair or unnecessary replacement.
I've had the machine only about three years, but it's seen some heavy use with two small boys in the house ...so it's worn maybe more like double its real age (how i feel getting out of bed some mornings).
The lockout seems to be an overheat protection rather than anything broken.
The dryer works by sucking air out of the right hand side of the drum, through a clear(ish), flat plastic tube to a metal fan chamber at the top, the fan blowing air into the heater chamber (wrapped in tin foil across the top), from where the hot air passes back into the drum through the slot at the top of the front door.
Thing is, some of the fibres and fluff washed and tumbled off clothes collects and clogs in the clear tube on its way to the fan ...some of it dry and thin like old wallpaper, but most of it (after some time) thick and staying damp like paper mache. Of course, when the tube gets blocked and the fan can't **** up enough air to blow across the heaters, i guess the heaters get over hot (mine was scorchio when i took the lid off straight after the second time it failed) and an overheat thermostat is tripped. There might be other forms of protection like pressure switches and current sensors, but hey we don't need to know if there are.
All you have to do is remove the tube and poke and flush out the fibre mache.
Before you start though, for heavens sake UNPLUG THE MACHINE! If it's wired into the wall, then at least remove the fuse or flick off the circuit breaker at the fuse box.
Unscrew the two screws at the top and behind the lid. Slide the lid back and lift off. Looks daunting doesn't it? Honestly though, don't worry about it.
Find and remove all the screws holding on the back panel (there are four to the rear of the top cross bar and one hiding behind a white grommet down the bottom of each side). Unclip the tube /cable holder at the top and knock /slide the back panel rearwards.
Down the right hand side, you'll see the clear flat suction tube. Prise the small tube off the top and the fan up until the suction tube can be pulled out from the side. Unscrew the hoseclip around the black rubber drum tube on the inside face, then prise the suction tube out of the base frame with a screwdriver and some care.
You'll then be able to flush /poke out the fibre mache with a hose and a wire coat hanger.
Reassembly is reverse of the above. Bingo, you're done.
Oh and if it still doesn't work, what have you lost by trying?