I had a WDM150 (the 1500 spin version of yours so would imagine it'd be much the same). I had this problem too. What happens is there is clear plastic void which runs down the back of the machine (on the side of the drawer) this is where cold water runs down condensing the hot steamy air. The problem is that the little black L-shaped rubber hose at the bottom ends up collecting all the fluff circulating in the hot air eventually blocking it. You can access this by taking the back off the machine (remember to turn off at the mains before you do this!!!!) The hose is secured with a plastic tie wrap at one end and a jubilee clip at the other. You'll need to provide another jubilee clip when reconnecting as this will need to be snipped off with careful use of side cutters. Clean all the gunk and fluuf out and reconnect it. In extreme cases the dryer overheats and a thermal cutout prevents the element from turning on. There is a reset for this mounted on the top of the metal jacket in which the element resides. You have to take the top off the machine to get at this. Be sure that you've cured the underlying problem first before resetting this as it will reoccur otherwise. You may find that (depending how often you use your dryer) you will periodically have to service the machine by cleaning out the pipe, I found I had to do it every 3-6 months. It is a really poor design which I would hope Hoover have resolved on their latest range. I no longer have mine because the main bearing went after only 3 years use and I was by this time sick of it in any case....
Gary McMeekin
August 2005
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