got the similar wd 860 model . good machine when it works for the first year then f13 fault occurs due to build up of fluff etc which gets hotter than normal. near the heater thermostats . it then sends a message to the machine saying something is burning to the machine which knocks the heater system off. no hot water or hot air for dryer.
need to remove whole top end of heater box , clean fully and change the two thermostats , approx £20 for both. it may hopefully work again !!
max
September 2010